Generic methods

Table of Contents

Command
Condition
Directory
Environment
File
Group
Http
Log
Logger
Package
Permissions
Schedule
Example
Service
Sharedfile
User
Variable
Usage

This section documents all the generic methods available in the Technique Editor.

Command

command_execution

Execute a command

Compatible with nodes running Rudder 4.1 or higher.

Parameters

command_name: Command name

Classes defined

command_execution_${command_name}_{kept, repaired, not_ok, reached}

command_execution_result

Execute a command and create outcome classes depending on its exit code

Compatible with nodes running Rudder 4.1 or higher.

Usage

Execute a command and create outcome classes depending on the exit codes given in parameters. If an exit code is not in the list it will lead to an error status. If you want 0 to be a success you have to list it in the kept_codes list

Parameters

command: The command to run
kept_codes: List of codes that produce a kept status separated with commas (ex: 1,2,5)
repaired_codes: List of codes that produce a repaired status separated with commas (ex: 3,4,6)

Classes defined

command_execution_result_${command}_{kept, repaired, not_ok, reached}

Condition

condition_from_command

Execute a command and create outcome classes depending on its exit code

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method executes a command, and defines a ${condition_prefix}_true or a ${condition_prefix}_false condition depending on the result of the command:

If the exit code is in the true_codes list, this will produce a kept outcome class and a ${condition_prefix}_true condition
If the exit code is in the false_codes list, this will produce a repaired outcome class and a ${condition_prefix}_false condition
If the exit code is not in the list, or if the command is not present, this will produce an error outcome class and no classes with ${condition_prefix}

The created condition is global to the agent.

Example

If you run a command /bin/check_network_status that output code 0, 1 or 2 in case of correct configuration, and 18 or 52 in case of invalid configuration, and you want to get this define a condition based on this command, you can use the following policy

condition_from_command("network_correctly_defined", "/bin/check_network_status", "0,1,2", "18,52")

If the command exits 0, 1 or 2, then it will define the following conditions network_correctly_defined_true, condition_from_command_network_correctly_defined_kept, condition_from_command_network_correctly_defined_reached
If the command exits 18, 52, then it will define the following conditions network_correctly_defined_false, condition_from_command_network_correctly_defined_kept, condition_from_command_network_correctly_defined_reached
If the command exits any other code, then it will define the following conditions condition_from_command_network_correctly_defined_error, condition_from_command_network_correctly_defined_reached
Finally, if the command is not present on the node, it will define condition_from_command_network_correctly_defined_error, condition_from_command_network_correctly_defined_reached

Parameters

condition_prefix: The condition name
command: The command to run
true_codes: List of codes that produce a true status separated with commas (ex: 1,2,5)
false_codes: List of codes that produce a false status separated with commas (ex: 3,4,6)

Classes defined

condition_from_command_${condition_prefix}_{kept, repaired, not_ok, reached}

condition_from_expression

Create a new condition class

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method evaluates an expression, and produces a ${condition_prefix}_true or a ${condition_prefix}_false condition depending on the result on the expression:

If the expression results in a "defined" state, this will produce a kept outcome class and a ${condition_prefix}_true condition
If the expression results in an "undefined" state, this will produce a kept outcome class and a ${condition_prefix}_false condition

Calling this method with a condition expression transforms a complex expression into a single class condition.

The created condition is global to the agent.

Example

If you want to check if a condition evaluates to true, like checking that you are on Monday, 2am, on RedHat systems, you can use the following policy

condition_from_expression("backup_time", "Monday.redhat.Hr02")

If the system is a RedHat like system, on Monday, at 2am, then it will define the following conditions backup_time_true, condition_from_expression_backup_time_kept, condition_from_expression_backup_time_reached
If the system not a RedHat like system, or it’s not Monday, or it’s not 2am, then it will define the following conditions backup_time_false, condition_from_expression_backup_time_kept, condition_from_expression_backup_time_reached
If the condition is invalid (cannot be parsed), it will define only condition_from_expression_backup_time_kept, condition_from_expression_backup_time_reached

Parameters

condition_prefix: The condition prefix
condition_expression: The expression evaluated to create the condition (use any to always evaluate to true)

Classes defined

condition_from_expression_${condition_prefix}_{kept, repaired, not_ok, reached}

condition_from_expression_persistent

Create a new condition class that persists across runs

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method evaluates an expression, and produces a ${condition_prefix}_true or a ${condition_prefix}_false condition depending on the result on the expression, that lasts for the duration time:

If the expression results in a "defined" state, this will produce a kept outcome class and a ${condition_prefix}_true condition
If the expression results in an "undefined" state, this will produce a kept outcome class and a ${condition_prefix}_false condition

Calling this method with a condition expression transforms a complex expression into a single class condition.

The created condition is global to the agent and is persisted across runs. The persistence duration is controlled using ${duration}; it defines for how long the resulting condition will be defined (in minutes). Note that there is no way to persist indefinitely.

Example

If you want to check if a condition evaluates to true, like checking that you are on Monday, 2am, on RedHat systems, and make it last one hour you can use the following policy

condition_from_expression_persistent_("backup_time", "Monday.redhat.Hr02", "60")

If the system is a RedHat like system, on Monday, at 2am, then it will define the following conditions backup_time_true, condition_from_expression_persistent_backup_time_kept, condition_from_expression_persistent_backup_time_reached
If the system not a RedHat like system, or it’s not Monday, or it’s not 2am, then it will define the following conditions backup_time_false, condition_from_expression_persistent_backup_time_kept, condition_from_expression_persistent_backup_time_reached
If the condition is invalid (cannot be parsed), it will define only condition_from_expression_persistent_backup_time_kept, condition_from_expression_persistent_backup_time_reached

Parameters

condition_prefix: The condition prefix
condition_expression: The expression evaluated to create the condition (use any to always evaluate to true)
duration: The persistence suffix in minutes

Classes defined

condition_from_expression_persistent_${condition_prefix}_{kept, repaired, not_ok, reached}

Environment

environment_variable_present

Enforce an environment variable value. Caution, the new environment variable will not be usable by the agent until it is restarted

Compatible with nodes running Rudder 4.1 or higher.

Parameters

name: Name of the environment variable
value: Value of the environment variable

Classes defined

environment_variable_present_${name}_{kept, repaired, not_ok, reached}

File

file_check_FIFO_pipe

Checks if a file exists and is a FIFO/Pipe

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_FIFO_pipe_${file_name}_{ok, reached, kept} if the file is a FIFO, or file_check_FIFO_pipe_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a fifo or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_FIFO_pipe_${file_name}_{kept, repaired, not_ok, reached}

file_check_block_device

Checks if a file exists and is a block device

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_block_device_${file_name}_{ok, reached, kept} if the file is a block_device, or file_check_block_device_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a block device or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_block_device_${file_name}_{kept, repaired, not_ok, reached}

file_check_character_device

Checks if a file exists and is a character device

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_character_device_${file_name}_{ok, reached, kept} if the file is a character device, or file_check_character_device_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a character device or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_character_device_${file_name}_{kept, repaired, not_ok, reached}

file_check_exists

Checks if a file exists

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_exists_${file_name}_{ok, reached, kept} if the file exists, or file_check_exists_${file_name}_{not_ok, reached, not_kept, failed} if the file doesn’t exists

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_exists_${file_name}_{kept, repaired, not_ok, reached}

file_check_hardlink

Checks if two files are the same (hard links)

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_hardlink_${file_name_1}_{ok, reached, kept} if the two files ${file_name_1} and ${file_name_2} are hard links of each other, or file_check_hardlink_${file_name_1}_{not_ok, reached, not_kept, failed} if if the files are not hard links.

Parameters

file_name_1: File name #1 (absolute path on the target node)
file_name_2: File name #2 (absolute path on the target node)

Classes defined

file_check_hardlink_${file_name_1}_{kept, repaired, not_ok, reached}

file_check_regular

Checks if a file exists and is a regular file

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_regular_${file_name}_{ok, reached, kept} if the file is a regular_file, or file_check_regular_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a regular file or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_regular_${file_name}_{kept, repaired, not_ok, reached}

file_check_socket

Checks if a file exists and is a socket

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_socket_${file_name}_{ok, reached, kept} if the file is a socket, or file_check_socket_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a socket or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_socket_${file_name}_{kept, repaired, not_ok, reached}

file_check_symlink

Checks if a file exists and is a symlink

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_symlink_${file_name}_{ok, reached, kept} if the file is a symlink, or file_check_symlink_${file_name}_{not_ok, reached, not_kept, failed} if the file is not a symlink or does not exist

Parameters

file_name: File name (absolute path on the target node)

Classes defined

file_check_symlink_${file_name}_{kept, repaired, not_ok, reached}

file_check_symlinkto

Checks if first file is symlink to second file

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class file_check_symlinkto_${target}_{ok, reached, kept} if the file ${symlink} is a symbolic link to ${target}, or file_check_symlinkto_${target}_{not_ok, reached, not_kept, failed} if if it is not a symbolic link, or any of the files does not exist. The symlink’s path is resolved to the absolute path and checked against the target file’s path, which must also be an absolute path.

Parameters

symlink: Symbolic link (absolute path on the target node)
target: Target file (absolute path on the target node)

Classes defined

file_check_symlinkto_${symlink}_{kept, repaired, not_ok, reached}

file_copy_from_local_source

Ensure that a file or directory is copied from a local source

Compatible with nodes running Rudder 4.1 or higher.

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_copy_from_local_source_${destination}_{kept, repaired, not_ok, reached}

file_copy_from_local_source_recursion

Ensure that a file or directory is copied from a local source

Compatible with nodes running Rudder 4.1 or higher.

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)
recursion: Recursion depth to enforce for this path (0, 1, 2, …, inf)

Classes defined

file_copy_from_local_source_${destination}_{kept, repaired, not_ok, reached}

file_copy_from_local_source_with_check

Ensure that a file or directory is copied from a local source if a check command succeeds

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method is a conditionnal file copy.

It allows comparing the source and destination, and if they are different, call a command with the source file path as argument, and only update the destination if the commands succeeds (i.e. returns a code included in rc_ok).

Examples

# To copy a configuration file only if it passes a config test:
file_copy_from_local_source_with_check("/tmp/program.conf", "/etc/program.conf", "program --config-test", "0");

This will:

Compare /tmp/program.conf and /etc/program.conf, and return kept if files are the same
If not, it will execute program --config-test "/tmp/program.conf" and check the return code
If it is one of the rc_ok codes, it will copy /tmp/program.conf into /etc/program.conf and return a repaired
If not, it will return an error

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)
check_command: Command to run, it will get the source path as argument
rc_ok: Return codes to be considered as valid, separated by a comma (default is 0)

Classes defined

file_copy_from_local_source_with_check_${destination}_{kept, repaired, not_ok, reached}

file_copy_from_remote_source

Ensure that a file or directory is copied from a policy server

Compatible with nodes running Rudder 4.1 or higher.

Usage

Note: This method uses CFEngine file copy protocol, and can only download files from the policy server. To download a file from an external source, you can use HTTP with the file_download method.

This method requires that the policy server is configured to accept copy of the source file from the agents it will be applied to.

You have to write the full path of the file on the policy server, for example:

/home/myuser/myfile

If you are using Rudder, you can download a file from the shared files with:

/var/rudder/configuration-repository/shared-files/PATH_TO_YOUR_FILE

Parameters

source: Source file (absolute path on the policy server)
destination: Destination file (absolute path on the target node)

Classes defined

file_copy_from_remote_source_${destination}_{kept, repaired, not_ok, reached}

file_copy_from_remote_source_recursion

Ensure that a file or directory is copied from a policy server

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method requires that the policy server is configured to accept copy of the source file or directory from the agents it will be applied to.

You have to write the full path of the file or directory on the policy server, for example:

/home/myuser/mydirectory

If you are using Rudder, you can download a file from the shared files with:

/var/rudder/configuration-repository/shared-files/PATH_TO_YOUR_DIRECTORY_OR_FILE

Parameters

source: Source file (absolute path on the policy server)
destination: Destination file (absolute path on the target node)
recursion: Recursion depth to enforce for this path (0, 1, 2, …, inf)

Classes defined

file_copy_from_remote_source_${destination}_{kept, repaired, not_ok, reached}

file_create

Create a file if it doesn’t exist

Compatible with nodes running Rudder 4.1 or higher.

Parameters

target: File to create (absolute path on the target node)

Classes defined

file_create_${target}_{kept, repaired, not_ok, reached}

file_create_symlink

Create a symlink at a destination path and pointing to a source target except if a file or directory already exists.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_create_symlink_${destination}_{kept, repaired, not_ok, reached}

file_create_symlink_enforce

Create a symlink at a destination path and pointing to a source target. This is also possible to enforce its creation

Compatible with nodes running Rudder 4.1 or higher.

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)
enforce: Force symlink if file already exist (true or false)

Classes defined

file_create_symlink_${destination}_{kept, repaired, not_ok, reached}

file_create_symlink_force

Create a symlink at a destination path and pointing to a source target even if a file or directory already exists.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

source: Source file (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_create_symlink_${destination}_{kept, repaired, not_ok, reached}

file_download

Download a file if it does not exist, using curl with a fallback on wget

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method finds a HTTP command-line tool and downloads the given source into the destination.

It tries curl first, and wget as fallback.

Parameters

source: URL to download from
destination: File destination (absolute path on the target node)

Classes defined

file_download_${destination}_{kept, repaired, not_ok, reached}

file_enforce_content

Enforce the content of a file

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
lines: Line(s) to add in the file - if lines is a list, please use @{lines} to pass the iterator rather than iterating over each values
enforce: Enforce the file to contain only line(s) defined (true or false)

Classes defined

file_ensure_lines_present_${file}_{kept, repaired, not_ok, reached}

file_ensure_block_in_section

Ensure that a section contains exactly a text block

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
section_start: Start of the section
section_end: End of the section
block: Block representing the content of the section

Classes defined

file_ensure_block_in_section_${file}_{kept, repaired, not_ok, reached}

file_ensure_block_present

Ensure that a text block is present in a specific location

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
block: Block(s) to add in the file

Classes defined

file_ensure_block_present_${file}_{kept, repaired, not_ok, reached}

file_ensure_key_value

Ensure that the file contains a pair of "key separator value"

Compatible with nodes running Rudder 4.1 or higher.

Usage

Edit (or create) the file, and ensure it contains an entry key → value with arbitrary separator between the key and its value. If the key is already present, the method will change the value associated with this key.

Parameters

file: File name to edit (absolute path on the target node)
key: Key to define
value: Value to define
separator: Separator between key and value, for example "=" or " " (without the quotes)

Classes defined

file_ensure_key_value_${file}_{kept, repaired, not_ok, reached}

file_ensure_key_value_option

Ensure that the file contains a pair of "key separator value", with options on the spacing around the separator

Compatible with nodes running Rudder 4.1 or higher.

Usage

Parameters

file: File name to edit (absolute path on the target node)
key: Key to define
value: Value to define
option: Option for the spacing around the separator: strict, which prevent spacings (space or tabs) around separators, or lax which accepts any number of spaces around separators
separator: Separator between key and value, for example "=" or " " (without the quotes)

Classes defined

file_ensure_key_value_${file}_{kept, repaired, not_ok, reached}

file_ensure_key_value_parameter_in_list

Ensure that one parameter exists in a list of parameters, on one single line, in the right hand side of a key→values line

Compatible with nodes running Rudder 4.1 or higher.

Usage

Edit the file, and ensure it contains the defined parameter in the list of values on the right hand side of a key→values line. If the parameter is not there, it will be added at the end, separated by parameter_separator. Optionnaly, you can define leading and closing character to enclose the parameters If the key does not exist in the file, it will be added in the file, along with the parameter

Example

If you have an initial file (/etc/default/grub) containing

GRUB_CMDLINE_XEN="dom0_mem=16G"

To add parameter dom0_max_vcpus=32 in the right hand side of the line, you’ll need the following policy

file_ensure_key_value_parameter_in_list("/etc/default/grub", "GRUB_CMDLINE", "=", "dom0_max_vcpus=32", " ", "\"", "\"");

Parameters

file: File name to edit (absolute path on the target node)
key: Full key name
key_value_separator: character used to separate key and value in a key-value line
parameter: String representing the sub-value to ensure is present in the list of parameters that form the value part of that line
parameter_separator: Character used to separate parameters in the list
leading_char_separator: leading character of the parameters
closing_char_separator: closing character of the parameters

Classes defined

file_ensure_key_value_parameter_in_list_${file}_{kept, repaired, not_ok, reached}

file_ensure_key_value_parameter_not_in_list

Ensure that a parameter doesn’t exist in a list of parameters, on one single line, in the right hand side of a key→values line

Compatible with nodes running Rudder 4.1 or higher.

Usage

Edit the file, and ensure it does not contain the defined parameter in the list of values on the right hand side of a key→values line. If the parameter is there, it will be removed. Please note that the parameter can be a regular expression. It will also remove any whitespace character between the parameter and parameter_separator Optionnaly, you can define leading and closing character to enclose the parameters

Example

If you have an initial file (/etc/default/grub) containing

GRUB_CMDLINE_XEN="dom0_mem=16G dom0_max_vcpus=32"

To remove parameter dom0_max_vcpus=32 in the right hand side of the line, you’ll need the following policy

file_ensure_key_value_parameter_not_in_list("/etc/default/grub", "GRUB_CMDLINE", "=", "dom0_max_vcpus=32", " ", "\"", "\"");

Parameters

file: File name to edit (absolute path on the target node)
key: Full key name
key_value_separator: character used to separate key and value in a key-value line
parameter_regex: Regular expression matching the sub-value to ensure is not present in the list of parameters that form the value part of that line
parameter_separator: Character used to separate parameters in the list
leading_char_separator: leading character of the parameters
closing_char_separator: closing character of the parameters

Classes defined

file_ensure_key_value_parameter_not_in_list_${file}_{kept, repaired, not_ok, reached}

file_ensure_key_value_present_in_ini_section

Ensure that a key-value pair is present in a section in a specific location. The objective of this method is to handle INI-style files.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
section: Name of the INI-style section under which the line should be added or modified (not including the [] brackets)
name: Name of the key to add or edit
value: Value of the key to add or edit

Classes defined

file_ensure_key_value_present_in_ini_section_${file}_{kept, repaired, not_ok, reached}

file_ensure_keys_values

Ensure that the file contains all pairs of "key separator value", with arbitrary separator between each key and its value

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method ensures key-value pairs are present in a file.

Usage

This method will iterate over the key-value pairs in the dict, and:

If the key is not defined in the destination, add the key separator + value line.
If the key is already present in the file, replace the key separator + anything by key + separator + value

This method always ignores spaces and tabs when replacing (which means for example that key = value will match the = separator).

Keys are considered unique (to allow replacing the value), so you should use file_ensure_lines_present if you want to have multiple lines with the same key.

Example

If you have an initial file (/etc/myfile.conf) containing:

key1 = something
key3 = value3

To define key-value pairs, use the variable_dict or variable_dict_from_file methods.

For example, if you use the following content (stored in /tmp/data.json):

{
   "key1": "value1",
   "key2": "value2"
}

With the following policy:

# Define the `content` variable in the `configuration` prefix from the json file
variable_dict_from_file("configuration", "content", "/tmp/data.json")
# Enforce the presence of the key-value pairs
file_ensure_keys_values("/etc/myfile.conf", "configuration.content", " = ")

The destination file (/etc/myfile.conf) will contain:

key1 = value1
key3 = value3
key2 = value2

Parameters

file: File name to edit (absolute path on the target node)
keys: Name of the dict structure (without "${}") containing the keys (keys of the dict), and values to define (values of the dict)
separator: Separator between key and value, for example "=" or " " (without the quotes)

Classes defined

file_ensure_keys_values_${file}_{kept, repaired, not_ok, reached}

file_ensure_line_present_in_ini_section

Ensure that a line is present in a section in a specific location. The objective of this method is to handle INI-style files.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
section: Name of the INI-style section under which lines should be added (not including the [] brackets)
line: Line to ensure is present inside the section

Classes defined

file_ensure_line_present_in_ini_section_${file}_{kept, repaired, not_ok, reached}

file_ensure_line_present_in_xml_tag

Ensure that a line is present in a tag in a specific location. The objective of this method is to handle XML-style files. Note that if the tag is not present in the file, it won’t be added, and the edition will fail.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
tag: Name of the XML tag under which lines should be added (not including the <> brackets)
line: Line to ensure is present inside the section

Classes defined

file_ensure_line_present_in_xml_tag_${file}_{kept, repaired, not_ok, reached}

file_ensure_lines_absent

Ensure that a line is absent in a specific location

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
lines: Line(s) to remove in the file

Classes defined

file_ensure_lines_absent_${file}_{kept, repaired, not_ok, reached}

file_ensure_lines_present

Ensure that one or more lines are present in a file

Compatible with nodes running Rudder 4.1 or higher.

Parameters

file: File name to edit (absolute path on the target node)
lines: Line(s) to add in the file

Classes defined

file_ensure_lines_present_${file}_{kept, repaired, not_ok, reached}

file_from_string_mustache

Build a file from a mustache string

Compatible with nodes running Rudder 4.1 or higher.

Parameters

template: String containing a template to be expanded
destination: Destination file (absolute path on the target node)

Classes defined

file_from_string_mustache_${destination}_{kept, repaired, not_ok, reached}

file_from_template

Build a file from a legacy CFEngine template

Compatible with nodes running Rudder 4.1 or higher.

Usage

See file_from_template_type for general documentation about templates usage.

Parameters

source_template: Source file containing a template to be expanded (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_from_template_${destination}_{kept, repaired, not_ok, reached}

file_from_template_jinja2

Build a file from a jinja2 template

Compatible with nodes running Rudder 4.1 or higher.

Usage

See file_from_template_type for general documentation about templates usage.

This generic method will build a file from a jinja2 template using data (classes and variables) found in the execution context.

Setup

It requires to have the jinja2 python module installed on the node, it can usually be done in ncf with package_present("python-jinja2", "", "", "").

	Warning
	If you are using a jinja2 version older than 2.7 trailing newlines will not be preserved in the destination file.

Syntax

Jinja2 is a powerful templating language, running in Python. The Jinja2 syntax reference documentation is http://jinja.pocoo.org/docs/dev/templates/ which will likely be useful, as Jinja2 is very rich and allows a lot more that what is explained here.

This section presents some simple cases that cover what can be done with mustache templating, and the way the agent data is provided to the templating engine.

The main specificity of jinja2 templating is the use of two root containers:

classes to access currently defined classes
vars to access all currently defined variables

Note: You can add comments in the template, that will not be rendered in the output file with {# ... #}.

You can extend the Jinja2 templating engine by adding custom FILTERS and TESTS in the script /var/rudder/configuration-repository/ncf/10_ncf_internals/modules/templates/jinja2_custom.py

For instance, to add a filter to upperstring a string and a test if a number is odd, you can create the file /var/rudder/configuration-repository/ncf/10_ncf_internals/modules/extensions/jinja2_custom.py on your Rudder server with the following content:

def upperstring(input):
    return input.upper()

def odd(value):
    return True if (value % 2) else False

FILTERS = {'upperstring': upperstring}
TESTS = {'odd': odd}

These filters and tests will be usable in your jinja templates automatically.

Conditions

To display content based on classes definition:

{% if classes.my_class is defined  %}
   display this if defined
{% endif %}
{% if not classes.my_class is defined %}
   display this if not defined
{% endif %}

Note: You cannot use class expressions here.

You can also use other tests, for example other bilt-in ones or those defined in jinja2_custom.py:

{% if vars.variable_prefix.my_number is odd  %}
   display if my_number is odd
{% endif %}

Scalar variables

Here is how to display a scalar variable value (integer, string, …), if you have defined variable_string("variable_prefix", "my_variable", "my_value"):

{{ vars.variable_prefix.my_variable }}

You can also modify what is displayed by using filters. The built-in filters can be extended in jinja2_custom.py:

{{ vars.variable_prefix.my_variable | upperstring }}

Will display the variable in uppercase.

Iteration

To iterate over a list, for example defined with:

variable_iterator("variable_prefix", "iterator_name", "a,b,c", ",")

Use the following file:

{% for item in vars.variable_prefix.iterator_name %}
{{ item }} is the current iterator_name value
{% endfor %}

Which will be expanded as:

a is the current iterator_name value
b is the current iterator_name value
c is the current iterator_name value

To iterate over a container defined by the following json file, loaded with variable_dict_from_file("variable_prefix", "dict_name", "path"):

{
   "hosts": [
       "host1",
       "host2"
   ],
   "files": [
       {"name": "file1", "path": "/path1", "users": [ "user1", "user11" ] },
       {"name": "file2", "path": "/path2", "users": [ "user2" ] }
   ],
   "properties": {
       "prop1": "value1",
       "prop2": "value2"
   }
}

Use the following template:

{% for item in vars.variable_prefix.dict_name.hosts %}
{{ item }} is the current hosts value
{% endfor %}

# will display the name and path of the current file
{% for file in vars.variable_prefix.dict_name.files %}
{{ file.name }}: {{ file.path }}
{% endfor %}

# will display the users list of each file
{% for file in vars.variable_prefix.dict_name.files %}
{{ file.name }}: {{ file.users|join(' ') }}
{% endfor %}


# will display the current properties key/value pair
{% for key, value in vars.variable_prefix.dict_name.properties.items() %}
{{ key }} -> {{ value }}
{% endfor %}

Which will be expanded as:

host1 is the current hosts value
host2 is the current hosts value

# will display the name and path of the current file
file1: /path1
file2: /path2

# will display the users list of each file
file1: user1 user11
file2: user2

# will display the current properties key/value pair
prop1 -> value1
prop2 -> value2

Parameters

source_template: Source file containing a template to be expanded (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_from_template_${destination}_{kept, repaired, not_ok, reached}

file_from_template_mustache

Build a file from a mustache template

Compatible with nodes running Rudder 4.1 or higher.

Usage

See file_from_template_type for general documentation about templates usage.

Syntax

Mustache is a logic-less templating language, available in a lot of languages, and used for file templating in CFEngine. The mustache syntax reference is https://mustache.github.io/mustache.5.html.

We will here describe the way to get agent data into a template. Ass explained in the general templating documentation, we can access various data in a mustache template.

The main specificity compared to standard mustache syntax of prefixes in all expanded values:

classes to access classes
vars to access all variables

Classes

Here is how to display content depending on classes definition:

{{#classes.my_class}}
   content when my_class is defined
{{/classes.my_class}}

{{^classes.my_class}}
   content when my_class is *not* defined
{{/classes.my_class}}

Note: You cannot use class expressions here.

Scalar variable

Here is how to display a scalar variable value (integer, string, …), if you have defined variable_string("variable_prefix", "my_variable", "my_value"):

{{{vars.variable_prefix.my_variable}}}

We use the triple {{{ }}} to avoid escaping html entities.

Iteration

Iteration is done using a syntax similar to scalar variables, but applied on container variables.

Use {{#vars.container}} content {{/vars.container}} to iterate
Use {{{.}}} for the current element value in iteration
Use {{{.key}}} for the key value in current element
Use {{{@}}} for the current element key in iteration

To iterate over a list, for example defined with:

variable_iterator("variable_prefix", "iterator_name", "a,b,c", ",")

Use the following file:

{{#vars.variable_prefix.iterator_name}}
{{{.}}} is the current iterator_name value
{{/vars.variable_prefix.iterator_name}}

Which will be expanded as:

a is the current iterator_name value
b is the current iterator_name value
c is the current iterator_name value

To iterate over a container defined by the following json file, loaded with variable_dict_from_file("variable_prefix", "dict_name", "path"):

{
   "hosts": [
       "host1",
       "host2"
   ],
   "files": [
       {"name": "file1", "path": "/path1", "users": [ "user1", "user11" ] },
       {"name": "file2", "path": "/path2", "users": [ "user2" ] }
   ],
   "properties": {
       "prop1": "value1",
       "prop2": "value2"
   }
}

Use the following template:

{{#vars.variable_prefix.dict_name.hosts}}
{{{.}}} is the current hosts value
{{/vars.variable_prefix.dict_name.hosts}}

# will display the name and path of the current file
{{#vars.variable_prefix.dict_name.files}}
{{{.name}}}: {{{.path}}}
{{/vars.variable_prefix.dict_name.files}}

# will display the users list of each file
{{#vars.variable_prefix.dict_name.files}}
{{{.name}}}:{{#users}} {{{.}}}{{/users}}
{{/vars.variable_prefix.dict_name.files}}


# will display the current properties key/value pair
{{#vars.variable_prefix.dict_name.properties}}
{{{@}}} -> {{{.}}}
{{/vars.variable_prefix.dict_name.properties}}

Which will be expanded as:

host1 is the current hosts value
host2 is the current hosts value

# will display the name and path of the current file
file1: /path1
file2: /path2

# will display the users list of each file
file1: user1 user11
file2: user2

# will display the current properties key/value pair
prop1 -> value1
prop2 -> value2

Note: Starting from CFEngine 3.7, you can use {{#-top-}} ... {{/-top-}} to iterate over the top level container.

Parameters

source_template: Source file containing a template to be expanded (absolute path on the target node)
destination: Destination file (absolute path on the target node)

Classes defined

file_from_template_${destination}_{kept, repaired, not_ok, reached}

file_from_template_type

Build a file from a template

Compatible with nodes running Rudder 4.1 or higher.

Usage

These methods write a file based on a provided template and the data available to the agent.

Usage

To use these methods (file_from_template_*), you need to have:

a template file
data to fill this template

The template file should be somewhere on the local file system, so if you want to use a file shared from the policy server, you need to copy it first (using file_copy_from_remote_source).

It is common to use a specific folder to store those templates after copy, for example in ${sys.workdir}/templates/.

The data that will be used while expanding the template is the data available in the agent at the time of expansion. That means:

CFEngine's sytem variables (${sys.*}, …) and classes (linux, ``)
data defined during execution (outcome classes of generic methods, …)
classes based on condition_ generic methods
data defined in ncf using variable_* generic methods, which allow for example to load data from local json or yaml files.

Template types

ncf currently supports three templating languages:

mustache templates, which are documented in file_from_template_mustache
jinja2 templates, which are documented in file_from_template_jinja2
CFEngine templates, which are a legacy implementation that is here for compatibility, and should not be used for new templates.

Example

Here is a complete example of templating usage:

The (basic) template file, present on the server in /PATH_TO_MY_FILE/ntp.conf.mustache (for syntax reference, see file_from_template_mustache):

{{#classes.linux}}
server {{{vars.configuration.ntp.hostname}}}
{{/classes.linux}}
{{^classes.linux}}
server hardcoded.server.example
{{/classes.linux}}

And on your local node in /tmp/ntp.json, the following json file:

{ "hostname": "my.hostname.example" }

And the following policy:

# Copy the file from the policy server
file_copy_from_remote_source("/PATH_TO_MY_FILE/ntp.conf.mustache", "${sys.workdir}/templates/ntp.conf.mustache")
# Define the `ntp` varibale in the `configuration` prefix from the json file
variable_dict_from_file("configuration", "ntp", "/tmp/ntp.json")
# Expand yout template
file_from_template_type("${sys.workdir}/templates/ntp.conf.mustache", "/etc/ntp.conf", "mustache")
# or
# file_from_template_mustache("${sys.workdir}/templates/ntp.conf.mustache", "/etc/ntp.conf")

The destination file will contain the expanded content, for example on a Linux node:

server my.hostname.example

Parameters

source_template: Source file containing a template to be expanded (absolute path on the target node)
destination: Destination file (absolute path on the target node)
template_type: Template type (cfengine, jinja2 or mustache)

Classes defined

file_from_template_${destination}_{kept, repaired, not_ok, reached}

file_remove

Remove a file if it exists

Compatible with nodes running Rudder 4.1 or higher.

Parameters

target: File to remove (absolute path on the target node)

Classes defined

file_remove_${target}_{kept, repaired, not_ok, reached}

file_replace_lines

Ensure that a line in a file is replaced by another one

Compatible with nodes running Rudder 4.1 or higher.

Usage

You can replace lines in a files, based on regular expression and captured pattern

Syntax

The content to match in the file is a PCRE regular expression, unanchored that you can replace with the content of replacement.

Content can be captured in regular expression, and be reused with the notation ${match.1} (for first matched content), ${match.2} for second, etc, and the special captured group ${match.0} for the whole text.

Example

Here is an example to remove enclosing specific tags

file_replace_lines("/PATH_TO_MY_FILE/file", "<my>(.*)<pattern>", "my ${match.1} pattern")

Parameters

file: File name to edit (absolute path on the target node)
line: Line to match in the file
replacement: Line to add in the file as a replacement

Classes defined

file_replace_lines_${file}_{kept, repaired, not_ok, reached}

file_template_expand

This is a bundle to expand a template in a specific location

WARNING: This generic method is deprecated. Use file_from_template instead.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

tml_file: File name (with full path within the framework) of the template file
target_file: File name (with full path) where to expand the template
mode: Mode of destination file
owner: Owner of destination file
group: Froup of destination file

Classes defined

file_template_expand_${target_file}_{kept, repaired, not_ok, reached}

Group

group_absent

Make sure a group is absent

Compatible with nodes running Rudder 4.1 or higher.

Parameters

group: Group name

Classes defined

group_absent_${group}_{kept, repaired, not_ok, reached}

group_present

Create a group

Compatible with nodes running Rudder 4.1 or higher.

Parameters

group: Group name

Classes defined

group_present_${group}_{kept, repaired, not_ok, reached}

Http

http_request_check_status_headers

Checks status of an HTTP URL

Compatible with nodes running Rudder 4.1 or higher.

Usage

Perform a HTTP request on the URL, method and headers provided and check that the response has the expected status code (ie 200, 404, 503, etc)

Parameters

method: Method to call the URL (GET, POST, PUT, DELETE)
url: URL to query
expected_status: Expected status code of the HTTP response
headers: Headers to include in the HTTP request (as a string, without ')

Classes defined

http_request_check_status_headers_${url}_{kept, repaired, not_ok, reached}

http_request_content_headers

Make an HTTP request with a specific header

Compatible with nodes running Rudder 4.1 or higher.

Usage

Perform a HTTP request on the URL, method and headers provided and send the content provided. Will return an error if the request failed.

Parameters

method: Method to call the URL (POST, PUT)
url: URL to send content to
content: Content to send
headers: Headers to include in the HTTP request

Classes defined

http_request_content_headers_${url}_{kept, repaired, not_ok, reached}

Log

log_rudder

Logging output for Rudder reports

Compatible with nodes running Rudder 4.1 or higher.

Parameters

message: The common part of the message to display
old_class_prefix: The prefix of the class for different states (0.x version, empty to force new style logging only)
origin_class_prefix: The prefix of the class for different states (1.x version)
args: The arguments used to call the generic method (slist)

Classes defined

logger_rudder_${old_class_prefix}_{kept, repaired, not_ok, reached}

Logger

logger_rudder

Logging output for Rudder reports. This interface is for compatiblity with older generic methods and techniques, and is replaced by log_rudder.

WARNING: This generic method is deprecated. Use log_rudder instead.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

message: The common part of the message to display
old_class_prefix: The prefix of the class for different states (0.x version, empty to force new style logging only)

Classes defined

logger_rudder_${old_class_prefix}_{kept, repaired, not_ok, reached}

Package

package_absent

Enforce the absence of a package

Compatible with nodes running Rudder 4.1 or higher.

Usage

See package_state for documentation.

Parameters

name: Name of the package
version: Version of the package or "any" for any version (defaults to "any")
architecture: Architecture of the package, can be an architecture name or "default" (defaults to "default")
provider: Package provider to use, can be "yum", "apt", "zypper", "zypper_pattern", "slackpkg", "pkg" or "default" for system default package manager (defaults to "default")

Classes defined

package_absent_${name}_{kept, repaired, not_ok, reached}

package_check_installed

Verify if a package is installed in any version

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class package_check_installed_${file_name}_{ok, reached, kept} if the package is installed, or package_check_installed_${file_name}_{not_ok, reached, not_kept, failed} if the package is not installed

Parameters

package_name: Name of the package to check

Classes defined

package_check_installed_${package_name}_{kept, repaired, not_ok, reached}

package_install

Install or update a package in its latest version available

WARNING: This generic method is deprecated. Use package_present instead.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

package_name: Name of the package to install

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

package_install_version

Install or update a package in a specific version

WARNING: This generic method is deprecated. Use package_present instead.

Compatible with nodes running Rudder 4.1 or higher.

Parameters

package_name: Name of the package to install
package_version: Version of the package to install (can be "latest" to install it in its latest version)

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

package_install_version_cmp

Install a package or verify if it is installed in a specific version, or higher or lower version than a version specified

WARNING: This generic method is deprecated. Use package_present instead.

Compatible with nodes running Rudder 4.1 or higher.

Usage

Example:

methods:
    "any" usebundle => package_install_version_cmp("postgresql", ">=", "9.1", "verify");

Parameters

package_name: Name of the package to install or verify
version_comparator: Comparator between installed version and defined version, can be ==,⇐,>=,<,>,!=
package_version: The version of the package to verify (can be "latest" for latest version)
action: Action to perform, can be add, verify (defaults to verify)

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

package_install_version_cmp_update

Install a package or verify if it is installed in a specific version, or higher or lower version than a version specified, optionally test update or not (Debian-, Red Hat- or SuSE-like systems only)

WARNING: This generic method is deprecated. Use package_present instead.

Compatible with nodes running Rudder 4.1 or higher.

Usage

Example:

methods:
    "any" usebundle => package_install_version_cmp_update("postgresql", ">=", "9.1", "verify", "false");

Parameters

package_name: Name of the package to install or verify
version_comparator: Comparator between installed version and defined version, can be ==,⇐,>=,<,>,!=
package_version: The version of the package to verify (can be "latest" for latest version)
action: Action to perform, can be add, verify (defaults to verify)
update_policy: While verifying packages, check against latest version ("true") or just installed ("false")

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

package_present

Enforce the presence of a package

Compatible with nodes running Rudder 4.1 or higher.

Usage

See package_state for documentation.

Parameters

name: Name of the package, or path to a local package
version: Version of the package, can be "latest" for latest version or "any" for any version (defaults to "any")
architecture: Architecture of the package, can be an architecture name or "default" (defaults to "default")
provider: Package provider to use, can be "yum", "apt", "zypper", "zypper_pattern", "slackpkg", "pkg" or "default" for system default package manager (defaults to "default")

Classes defined

package_present_${name}_{kept, repaired, not_ok, reached}

package_remove

Remove a package

WARNING: This generic method is deprecated. Use package_absent instead.

Compatible with nodes running Rudder 4.1 or higher.

Usage

Example:

methods:
    "any" usebundle => package_remove("htop");

Parameters

package_name: Name of the package to remove

Classes defined

package_remove_${package_name}_{kept, repaired, not_ok, reached}

package_state

Enforce the state of a package

Compatible with nodes running Rudder 4.1 or higher.

Usage

These methods manage packages using a package manager on the system.

package_present and package_absent use a new package implementation, different from package_install_*, package_remove_* and package_verify_*. It should be more reliable, and handle upgrades better. It is compatible though, and you can call generic methods from both implementations on the same host. The only drawback is that the agent will have to maintain double caches for package lists, which may cause a little unneeded overhead.

Setup

If you are using ncf inside Rudder, no specific setup is necessary.

If your are using ncf without Rudder, you need to call the initialization bundle before using package methods.

Package parameters

There is only one mandatory parameter, which is the package name to install. When it should be installed from a local package, you need to specify the full path to the package as name.

The version parameter allows specifying a version you want installed. It should be the complete versions string as used by the used package manager. This parameter allows two special values:

any which is the default value, and is satisfied by any version of the given package
latest which will ensure, at each run, that the package is at the latest available version.

The last parameter is the provider, which is documented in the next section.

You can use package_state_options to pass options to the underlying package manager (currently only with apt package manager).

Package providers

This method supports several package managers. You can specify the package manager you want to use or let the method choose the default for the local system.

The package providers include a caching system for package information. The package lists (installed, available and available updates) are only updated when the cache expires, or when an operation is made by the agent on packages.

Note: The implementation of package operations is done in scripts called modules, which you can find in ${sys.workdir}/modules/packages/.

apt

This package provider uses apt/dpkg to manage packages on the system. dpkg will be used for all local actions, and apt is only needed to manage update and installation from a repository.

rpm

This package provider uses yum/rpm to manage packages on the system. rpm will be used for all local actions, and yum is only needed to manage update and installation from a repository.

It is able to downgrade packages when specifying an older version.

zypper

This package provider uses zypper/rpm to manage packages on the system. rpm will be used for all local actions, and zypper is only needed to manage update and installation from a repository.

Note: If the package version you want to install contains an epoch, you have to specify it in the version in the epoch:version form, like reported by zypper info.

zypper_pattern

This package provider uses zypper with the -t pattern option to manage zypper patterns or meta-packages on the system.

Since a zypper pattern can be named differently than the rpm package name providing it, please always use the exact pattern name (as listed in the output of zypper patterns) when using this provider.

Note: When installing a pattern from a local rpm file, Rudder assumes that the pattern is built following the official zypper documentation.

Older implementations of zypper patterns may not be supported by this module.

slackpkg

This package provider uses Slackware’s installpkg and upgradepkg tools to manage packages on the system

pkg

This package provider uses FreeBSD’s pkg to manage packages on the system.

Examples

# To install postgresql in version 9.1 for x86_64 atchitecture
package_present("postgresql", "9.1", "x86_64", "");
# To ensure postgresql is always in the latest available version
package_present("postgresql", "latest", "", "");
# To ensure installing postgresql in any version
package_present("postgresql", "", "", "");
# To ensure installing postgresql in any version, forcing the yum provider
package_present("postgresql", "", "", "yum");
# To ensure installing postgresql from a local package
package_present("/tmp/postgresql-9.1-1.x86_64.rpm", "", "", "");
# To remove postgresql
package_absent("postgresql", "", "", "");

Parameters

name: Name of the package, or path to a local package if state is present
version: Version of the package, can be "latest" for latest version or "any" for any version (defaults to "any")
architecture: Architecture of the package, can be an architecture name or "default" (defaults to "default")
provider: Package provider to use, can be "yum", "apt", "zypper", "zypper_pattern", "slackpkg", "pkg" or "default" for system default package manager (defaults to "default")
state: State of the package, can be "present" or "absent" (defaults to "present")

Classes defined

package_state_${name}_{kept, repaired, not_ok, reached}

package_state_options

Enforce the state of a package with options

Compatible with nodes running Rudder 4.1 or higher.

Usage

See package_state for documentation.

Parameters

name: Name of the package, or path to a local package if state is present
version: Version of the package, can be "latest" for latest version or "any" for any version (defaults to "any")
architecture: Architecture of the package, can be an architecture name or "default" (defaults to "default")
provider: Package provider to use, can be "yum", "apt", "zypper", "zypper_pattern", "slackpkg", "pkg" or "default" for system default package manager (defaults to "default")
state: State of the package, can be "present" or "absent" (defaults to "present")
options: Options no pass to the package manager (defaults to empty)

Classes defined

package_state_options_${name}_{kept, repaired, not_ok, reached}

package_verify

Verify if a package is installed in its latest version available

Compatible with nodes running Rudder 4.1 or higher.

Parameters

package_name: Name of the package to verify

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

package_verify_version

Verify if a package is installed in a specific version

Compatible with nodes running Rudder 4.1 or higher.

Parameters

package_name: Name of the package to verify
package_version: Version of the package to verify (can be "latest" for latest version)

Classes defined

package_install_${package_name}_{kept, repaired, not_ok, reached}

Permissions

permissions

Set permissions on a file or directory (non recursively)

Compatible with nodes running Rudder 4.1 or higher.

Parameters

path: Path to the file/directory
mode: Mode to enforce (like "640")
owner: Owner to enforce (like "root")
group: Group to enforce (like "wheel")

Classes defined

permissions_${path}_{kept, repaired, not_ok, reached}

permissions_dirs

Verify if a directory has the right permissions non recursively

Compatible with nodes running Rudder 4.1 or higher.

Parameters

path: Path of the directory
mode: Mode to enforce
owner: Owner to enforce
group: Group to enforce

Classes defined

permissions_${path}_{kept, repaired, not_ok, reached}

permissions_dirs_recurse

Verify if a directory has the right permissions recursively

Compatible with nodes running Rudder 4.1 or higher.

Parameters

path: Path to the directory
mode: Mode to enforce
owner: Owner to enforce
group: Group to enforce

Classes defined

permissions_${path}_{kept, repaired, not_ok, reached}

permissions_recurse

Verify if a file or directory has the right permissions recursively

Compatible with nodes running Rudder 4.1 or higher.

Parameters

path: Path to the file / directory
mode: Mode to enforce
owner: Owner to enforce
group: Group to enforce

Classes defined

permissions_${path}_{kept, repaired, not_ok, reached}

permissions_type_recursion

Ensure that a file or directory is present and has the right mode/owner/group

Compatible with nodes running Rudder 4.1 or higher.

Parameters

path: Path to edit
mode: Mode of the path to edit
owner: Owner of the path to edit
group: Group of the path to edit
type: Type of the path to edit (all/files/directories)
recursion: Recursion depth to enforce for this path (0, 1, 2, …, inf)

Classes defined

permissions_${path}_{kept, repaired, not_ok, reached}

Schedule

schedule_simple

Trigger a repaired outcome when a job should be run

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method compute the expected time for running the job, based on the parameters and splayed uing system ids, and define a conditions based on this computation: * schedule_simple_${job_id}_kept if the job should not be run now * schedule_simple_${job_id}_repaired if the job should be run * schedule_simple_${job_id}_error if their is an inconsistency in the method parameters

Example

If you want to run a job, at every hour and half-hour (0:00 and 0:30), with no spread across system, with an agent running with default schedule of 5 minutes, and making sure that the job is run (if the agent couldn’t run it, then at the next agent execution the job should be run), you will call the method with the following parameters:

schedule_simple("job_schedule_id", "5", "0", "0",  "0", "0", "0",  "30", "0", "0", "catchup")

During each run right after o’clock and half-hour, this method will define the condition schedule_simple_job_schedule_id_repaired, that you can use as a condition for a generic method command_execution

Parameters

job_id: A string to identify this job
agent_periodicity: Agent run interval (in minutes)
max_execution_delay_minutes: On how many minutes you want to spread the job
max_execution_delay_hours: On how many hours you want to spread the job
start_on_minutes: At which minute should be the first run
start_on_hours: At which hour should be the first run
start_on_day_of_week: At which day of week should be the first run
periodicity_minutes: Desired job run interval (in minutes)
periodicity_hours: Desired job run interval (in hours)
periodicity_days: Desired job run interval (in days)
mode: "nodups": avoid duplicate runs in the same period / "catchup": avoid duplicates and one or more run have been missed, run once before next period / "stateless": no check is done on past runs

Classes defined

schedule_simple_${job_id}_{kept, repaired, not_ok, reached}

schedule_simple_catchup

Trigger a repaired outcome when a job should be run (avoid losing a job)

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class schedule_simple_${job_id}_{kept,repaired,not_ok,ok,reached} * _ok or _kept for when there is nothing to do * _repaired if the job should run * _not_ok and _reached have their usual meaning If the agent run is skipped during the period, method tries to catchup the run on next agent run. If the agent run is skipped twice,, only one run is catched up. If the agent is run twice (for example from a manual run), the job is run only once.

Parameters

job_id: A string to identify this job
agent_periodicity: Agent run interval (in minutes)
max_execution_delay_minutes: On how many minutes you want to spread the job
max_execution_delay_hours: On how many hours you want to spread the job
start_on_minutes: At which minute should be the first run
start_on_hours: At which hour should be the first run
start_on_day_of_week: At which day of week should be the first run
periodicity_minutes: Desired job run interval (in minutes)
periodicity_hours: Desired job run interval (in hours)
periodicity_days: Desired job run interval (in days)

Classes defined

schedule_simple_${job_id}_{kept, repaired, not_ok, reached}

schedule_simple_nodups

Trigger a repaired outcome when a job should be run (avoid running twice)

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class schedule_simple_${job_id}_{kept,repaired,not_ok,ok,reached} * _ok or _kept for when there is nothing to do * _repaired if the job should run * _not_ok and _reached have their usual meaning If the agent is run twice (for example from a manual run), the jo is run only once. However if the agent run is skipped during the period, the job is never run.

Parameters

job_id: A string to identify this job
agent_periodicity: Agent run interval (in minutes)
max_execution_delay_minutes: On how many minutes you want to spread the job
max_execution_delay_hours: On how many hours you want to spread the job
start_on_minutes: At which minute should be the first run
start_on_hours: At which hour should be the first run
start_on_day_of_week: At which day of week should be the first run
periodicity_minutes: Desired job run interval (in minutes)
periodicity_hours: Desired job run interval (in hours)
periodicity_days: Desired job run interval (in days)

Classes defined

schedule_simple_${job_id}_{kept, repaired, not_ok, reached}

schedule_simple_stateless

Trigger a repaired outcome when a job should be run (without checks)

Compatible with nodes running Rudder 4.1 or higher.

Usage

This bundle will define a class schedule_simple_${job_id}_{kept,repaired,not_ok,ok,reached} * _ok or _kept for when there is nothing to do * _repaired if the job should run * _not_ok and _reached have their usual meaning No effort is done to check if a run has already been done for this period or not. If the agent is run twice, the job will be run twice, and if the agent is not run, the job will no be run.

Parameters

job_id: A string to identify this job
agent_periodicity: Agent run interval (in minutes)
max_execution_delay_minutes: On how many minutes you want to spread the job
max_execution_delay_hours: On how many hours you want to spread the job
start_on_minutes: At which minute should be the first run
start_on_hours: At which hour should be the first run
start_on_day_of_week: At which day of week should be the first run
periodicity_minutes: Desired job run interval (in minutes)
periodicity_hours: Desired job run interval (in hours)
periodicity_days: Desired job run interval (in days)

Classes defined

schedule_simple_${job_id}_{kept, repaired, not_ok, reached}

Service

service_action

Trigger an action on a service using the approriate tool

Compatible with nodes running Rudder 4.1 or higher.

Usage

The service_* methods manage the services running on the system.

Parameters

Service name

The name of the service is the name understood by the service manager, except for the is-active-process action, where it is the regex to match against the running processes list.

Action

The action is the name of an action to run on the given service. The following actions can be used:

start
stop
restart
reload (or refresh)
is-active (or status)
is-active-process (in this case, the "service" parameter is the regex to match againt process list)
enable
disable
is-enabled

Other actions may also be used, depending on the selected service manager.

Implementation

These methods will detect the method to use according to the platform. You can run the methods with an info verbosity level to see which service manager will be used for a given action.

	Warning
	Due to compatibility issues when mixing calls to systemctl and service/init.d, when an init script exists, we will not use systemctl compatibility layer but directly service/init.d.

The supported service managers are:

systemd (any unkown action will be passed directly)
upstart
smf (for Solaris)
service command (for non-boot actions, any unkown action will be passed directly)
/etc/init.d scripts (for non-boot actions, any unkown action will be passed directly)
SRC (for AIX) (for non-boot actions)
chkconfig (for boot actions)
update-rc.d (for boot actions)
chitab (for boot actions)
links in /etc/rcX.d (for boot actions)
Windows services

Examples

# To restart the apache2 service
service_action("apache2", "restart");
service_restart("apache2");

Parameters

service_name: Name of the service
action: Action to trigger on the service (start, stop, restart, reload, …)

Classes defined

service_action_${service_name}_{kept, repaired, not_ok, reached}

service_check_disabled_at_boot

Check if a service is set to not start at boot using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, etc…)

Classes defined

service_check_disabled_at_boot_${service_name}_{kept, repaired, not_ok, reached}

service_check_running

Check if a service is running using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Process name

Classes defined

service_check_running_${service_name}_{kept, repaired, not_ok, reached}

service_check_running_ps

Check if a service is running using ps

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_regex: Regular expression used to select a process in ps output

Classes defined

service_check_running_${service_regex}_{kept, repaired, not_ok, reached}

service_check_started_at_boot

Check if a service is set to start at boot using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, etc…)

Classes defined

service_check_started_at_boot_${service_name}_{kept, repaired, not_ok, reached}

service_ensure_disabled_at_boot

Force a service not to be enabled at boot

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, etc…)

Classes defined

service_ensure_disabled_at_boot_${service_name}_{kept, repaired, not_ok, reached}

service_ensure_running

Ensure that a service is running using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, etc…)

Classes defined

service_ensure_running_${service_name}_{kept, repaired, not_ok, reached}

service_ensure_running_path

Ensure that a service is running using the appropriate method, specifying the path of the service in the ps output, or using Windows task manager

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, Windows, etc…)
service_path: Service with its path, as in the output from ps

Classes defined

service_ensure_running_${service_name}_{kept, repaired, not_ok, reached}

service_ensure_started_at_boot

Force a service to be started at boot

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service name (as recognized by systemd, init.d, Windows, SRC, SMF, etc…)

Classes defined

service_ensure_started_at_boot_${service_name}_{kept, repaired, not_ok, reached}

service_ensure_stopped

Ensure that a service is stopped using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Parameters

service_name: Service

Classes defined

service_ensure_stopped_${service_name}_{kept, repaired, not_ok, reached}

service_reload

Reload a service using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Usage

See service_action for documentation.

Parameters

service_name: Name of the service

Classes defined

service_reload_${service_name}_{kept, repaired, not_ok, reached}

service_restart

Restart a service using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Usage

See service_action for documentation.

Parameters

service_name: Name of the service

Classes defined

service_restart_${service_name}_{kept, repaired, not_ok, reached}

service_restart_if

Restart a service using the appropriate method if the specified class is true, otherwise it is considered as not required and success classes are returned.

WARNING: This generic method is deprecated. Use a condition with service_restart instead.

Compatible with nodes running Rudder 4.1 or higher.

Usage

See service_action for documentation.

Parameters

service_name: Name of the service
trigger_class: class(es) which will trigger the restart of Service "(package_service_installed|service_conf_changed)" by example

Classes defined

service_restart_${service_name}_{kept, repaired, not_ok, reached}

service_start

Start a service using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Usage

See service_action for documentation.

Parameters

service_name: Name of the service

Classes defined

service_start_${service_name}_{kept, repaired, not_ok, reached}

service_stop

Stop a service using the appropriate method

Compatible with nodes running Rudder 4.1 or higher.

Usage

See service_action for documentation.

Parameters

service_name: Name of the service

Classes defined

service_stop_${service_name}_{kept, repaired, not_ok, reached}

Sharedfile

sharedfile_from_node

This method retreives a file shared from another Rudder node

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method retreives a file shared from a Rudder node using a unique file identifier.

The file will be downloaded using CFEngine protocol and copied into a new file. The destination path must be the complete absolute path of the destination file.

See sharedfile_to_node for a complete example.

INFO: Please note that this method must be used on an agent that is connected to Rudder relay or server (>=4.1)

Parameters

source_uuid: which node to take the file from
file_id: unique name that was used to identify the file on the sender
file_path: where to put the file content

Classes defined

sharedfile_from_node_${file_id}_{kept, repaired, not_ok, reached}

sharedfile_to_node

This method shares a file with another Rudder node

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method shares a file with another Rudder node using a unique file identifier.

Read the Rudder documentation for a high level overview of file sharing between nodes.

The file will be kept on the policy server and transmitted to the destination node’s policy server if it is different. It will be kept on this server for the destination node to download as long as it is not replaced by a new file with the same id or remove by expiration of the TTL.

Parameters

This section describes the generic method parameters.

target_uuid

The node you want to share this file with. The uuid of a node is visible in the Nodes details (in the Web interface) or by entering rudder agent info on the target node.

file_id

This is a name that will be used to identify the file in the target node. It should be unique and describe the file content.

file_path

The local absolute path of the file to share.

ttl

The TTL can be:

A simple integer, in this case it is assumed to be a number of seconds
A string including units indications, the possible units are:
days, day or d
hours, hour, or h
minutes, minute, or m
seconds, second or s

The ttl value can look like 1day 2hours 3minutes 4seconds or can be abbreviated in the form 1d 2h 3m 4s, or without spaces 1d2h3m4s or any combination like 1day2h 3minute 4seconds Any unit can be skipped, but the decreasing order needs to be respected.

file_id

This is a name that will be used to identify the file once stored on the server. It should be unique and describe the file content.

Example:

We have a node A, with uuid 2bf1afdc-6725-4d3d-96b8-9128d09d353c which wants to share the /srv/db/application.properties with node B with uuid 73570beb-2d4a-43d2-8ffc-f84a6817849c.

We want this file to stay available for one year for node B on its policy server.

The node B wants to download it into /opt/application/etc/application.properties.

They have to agree (i.e. it has to be defined in the policies of both nodes) on the id of the file, that will be used during the exchange, here it will be application.properties.

To share the file, node A will use:

sharedfile_to_node("73570beb-2d4a-43d2-8ffc-f84a6817849c", "application.properties", "/srv/db/application.properties", "356 days")

To download the file, node B will use sharedfile_from_node with:

sharedfile_from_node("2bf1afdc-6725-4d3d-96b8-9128d09d353c", "application.properties", "/opt/application/etc/application.properties")

INFO: Please note that this method must be used on a Rudder agent (>=4.1) that is connected to Rudder relay or server (>=4.1)

Parameters

target_uuid: which node to share the file with
file_id: unique name that will be used to identify the file on the receiver
file_path: path of the file to share
ttl: time to keep the file on the policy server in seconds or in human readable form (see long description)

Classes defined

sharedfile_to_node_${file_id}_{kept, repaired, not_ok, reached}

User

user_absent

Remove a user

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method ensures that a user does not exist on the system.

Parameters

login: User login

Classes defined

user_absent_${login}_{kept, repaired, not_ok, reached}

user_create

Create a user

Compatible with nodes running Rudder 4.1 or higher.

Usage

This method does not create the user’s home directory.

Parameters

login: User login
description: User description
home: User’s home directory
group: User’s primary group
shell: User’s shell
locked: Is the user locked ? true or false

Classes defined

user_create_${login}_{kept, repaired, not_ok, reached}

Variable

variable_dict

Define a variable that contains key,value pairs (a dictionnary)

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name[key]} with each name replaced with the parameters of this method.

Be careful that using a global variable can lead to unpredictable content in case of multiple definition, which is implicitly the case when a technique has more than one instance (directive). Please note that only global variables are available within templates.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
value: The variable content in JSON format

Classes defined

variable_dict_${variable_name}_{kept, repaired, not_ok, reached}

variable_dict_from_file

Define a variable that contains key,value pairs (a dictionnary) from a JSON file

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name[key]} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
file_name: The file name with JSON content

Classes defined

variable_dict_from_file_${variable_name}_{kept, repaired, not_ok, reached}

variable_dict_merge

Define a variable resulting of the merge of two other variables

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name[key]} with each name replaced with the parameters of this method.

The resulting variable will be the merge of the two parameters, which means it is built by:

Taking the content of the first variable
Adding the content of the second variable, and replacing the keys that were already there

It is only a one-level merge, and the value of the first-level key will be completely replaced by the merge.

This method will fail if one of the variables is not defined. See variable_dict_merge_tolerant if you want to allow one of the variables not to be defined.

Usage

If you have a prefix.variable1 variable defined by:

{ "key1": "value1", "key2": "value2", "key3": { "keyx": "valuex" } }

And a prefix.variable2 variable defined by:

{ "key1": "different", "key3": "value3", "key4": "value4" }

And that you use:

variablr_dict_merge("prefix", "variable3, "prefix.variable1", "prefix.variable2")

You will get a prefix.variable3 variable containing:

{
  "key1": "different",
  "key2": "value2",
  "key3": "value3",
  "key4": "value4"
}

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
first_variable: The first variable, which content will be overriden in the resulting variable if necessary (written in the form variable_prefix.variable_name)
second_variable: The second variable, which content will override the first in the resulting variable if necessary (written in the form variable_prefix.variable_name)

Classes defined

variable_dict_merge_${variable_name}_{kept, repaired, not_ok, reached}

variable_dict_merge_tolerant

Define a variable resulting of the merge of two other variables, allowing merging undefined variables

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name[key]} with each name replaced with the parameters of this method.

See variable_dict_merge for usage documentation. The only difference is that this method will not fail if one of the variables do not exist, and will return the other one. If both are undefined, the method will still fail.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
first_variable: The first variable, which content will be overriden in the resulting variable if necessary (written in the form variable_prefix.variable_name)
second_variable: The second variable, which content will override the first in the resulting variable if necessary (written in the form variable_prefix.variable_name)

Classes defined

variable_dict_merge_tolerant_${variable_name}_{kept, repaired, not_ok, reached}

variable_iterator

Define a variable that will be automatically iterated over

Compatible with nodes running Rudder 4.1 or higher.

Usage

The generated variable is a special variable (slist in cfengine speaking) that is automatically iterated over. When you call a generic method with this variable as a parameter, n calls will be made, one for each items of the variable. Note: there is a limit of 10000 items

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
value: The variable content
separator: Regular expression that is used to split the value into items ( usually: , )

Classes defined

variable_iterator_${variable_name}_{kept, repaired, not_ok, reached}

variable_iterator_from_file

Define a variable that will be automatically iterated over

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
file_name: The path to the file
separator_regex: Regular expression that is used to split the value into items ( usually: )
comments_regex: Regular expression that is used to remove comments ( usually: #.*?(?=) )

Classes defined

variable_iterator_from_file_${variable_name}_{kept, repaired, not_ok, reached}

variable_string

Define a variable from a string parameter

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
value: The variable content

Classes defined

variable_string_${variable_name}_{kept, repaired, not_ok, reached}

variable_string_default

Define a variable from another variable name, with a default value if undefined

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
source_variable: The source variable name
default_value: The default value to use if source_variable is not defined

Classes defined

variable_string_default_${variable_name}_{kept, repaired, not_ok, reached}

variable_string_from_command

Define a variable from a command output

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
command: The command to execute

Classes defined

variable_string_from_command_${variable_name}_{kept, repaired, not_ok, reached}

variable_string_from_file

Define a variable from a file content

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

Parameters

variable_prefix: The prefix of the variable name
variable_name: The variable to define, the full name will be variable_prefix.variable_name
file_name: The path of the file

Classes defined

variable_string_from_file_${variable_name}_{kept, repaired, not_ok, reached}

variable_string_from_math_expression

Define a variable from a mathematical expression

Compatible with nodes running Rudder 4.1 or higher.

Usage

To use the generated variable, you must use the form ${variable_prefix.variable_name} with each name replaced with the parameters of this method.

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Rudder 4.1 - User ManualReference

Generic methods

Command

command_execution

command_execution_result

Condition

condition_from_command

Example

condition_from_expression

Example

condition_from_expression_persistent

Example

Directory

directory_absent

directory_check_exists

directory_create

Environment

environment_variable_present

File

file_check_FIFO_pipe

file_check_block_device

file_check_character_device

file_check_exists

file_check_hardlink

file_check_regular

file_check_socket

file_check_symlink

file_check_symlinkto

file_copy_from_local_source

file_copy_from_local_source_recursion

file_copy_from_local_source_with_check

Examples

file_copy_from_remote_source

file_copy_from_remote_source_recursion

file_create

file_create_symlink

file_create_symlink_enforce

file_create_symlink_force

file_download

file_enforce_content

file_ensure_block_in_section

file_ensure_block_present

file_ensure_key_value

file_ensure_key_value_option

file_ensure_key_value_parameter_in_list

Example

file_ensure_key_value_parameter_not_in_list

Example

file_ensure_key_value_present_in_ini_section

file_ensure_keys_values

Usage

Example

file_ensure_line_present_in_ini_section

file_ensure_line_present_in_xml_tag

file_ensure_lines_absent

file_ensure_lines_present

file_from_string_mustache

file_from_template

file_from_template_jinja2

Setup

Syntax

file_from_template_mustache

Syntax

file_from_template_type

Usage

Template types

Example

file_remove

file_replace_lines

Syntax

Example

file_template_expand

Group

group_absent

group_present

Http

http_request_check_status_headers

http_request_content_headers

Log

log_rudder