ansible.builtin.assemble module – Assemble configuration files from fragments

Note

This module is part of ansible-core and included in all Ansible installations. In most cases, you can use the short module name assemble even without specifying the collections: keyword. However, we recommend you use the FQCN for easy linking to the module documentation and to avoid conflicting with other collections that may have the same module name.

New in version 0.5: of ansible.builtin

Synopsis

  • Assembles a configuration file from fragments.

  • Often a particular program will take a single configuration file and does not support a conf.d style structure where it is easy to build up the configuration from multiple sources. assemble will take a directory of files that can be local or have already been transferred to the system, and concatenate them together to produce a destination file.

  • Files are assembled in string sorting order.

  • Puppet calls this idea fragments.

Note

This module has a corresponding action plugin.

Parameters

Parameter

Comments

attributes

aliases: attr

string

added in 2.3 of ansible.builtin

The attributes the resulting filesystem object should have.

To get supported flags look at the man page for chattr on the target system.

This string should contain the attributes in the same order as the one displayed by lsattr.

The = operator is assumed as default, otherwise + or - operators need to be included in the string.

backup

boolean

Create a backup file (if yes), including the timestamp information so you can get the original file back if you somehow clobbered it incorrectly.

Choices:

  • no ← (default)

  • yes

decrypt

boolean

added in 2.4 of ansible.builtin

This option controls the autodecryption of source files using vault.

Choices:

  • no

  • yes ← (default)

delimiter

string

added in 1.4 of ansible.builtin

A delimiter to separate the file contents.

dest

path / required

A file to create using the concatenation of all of the source files.

group

string

Name of the group that should own the filesystem object, as would be fed to chown.

ignore_hidden

boolean

added in 2.0 of ansible.builtin

A boolean that controls if files that start with a ‘.’ will be included or not.

Choices:

  • no ← (default)

  • yes

mode

raw

The permissions the resulting filesystem object should have.

For those used to /usr/bin/chmod remember that modes are actually octal numbers. You must either add a leading zero so that Ansible’s YAML parser knows it is an octal number (like 0644 or 01777) or quote it (like '644' or '1777') so Ansible receives a string and can do its own conversion from string into number.

Giving Ansible a number without following one of these rules will end up with a decimal number which will have unexpected results.

As of Ansible 1.8, the mode may be specified as a symbolic mode (for example, u+rwx or u=rw,g=r,o=r).

If mode is not specified and the destination filesystem object does not exist, the default umask on the system will be used when setting the mode for the newly created filesystem object.

If mode is not specified and the destination filesystem object does exist, the mode of the existing filesystem object will be used.

Specifying mode is the best way to ensure filesystem objects are created with the correct permissions. See CVE-2020-1736 for further details.

owner

string

Name of the user that should own the filesystem object, as would be fed to chown.

regexp

string

Assemble files only if regex matches the filename.

If not set, all files are assembled.

Every “" (backslash) must be escaped as “\” to comply to YAML syntax.

Uses Python regular expressions.

remote_src

boolean

added in 1.4 of ansible.builtin

If no, it will search for src at originating/master machine.

If yes, it will go to the remote/target machine for the src.

Choices:

  • no

  • yes ← (default)

selevel

string

The level part of the SELinux filesystem object context.

This is the MLS/MCS attribute, sometimes known as the range.

When set to _default, it will use the level portion of the policy if available.

serole

string

The role part of the SELinux filesystem object context.

When set to _default, it will use the role portion of the policy if available.

setype

string

The type part of the SELinux filesystem object context.

When set to _default, it will use the type portion of the policy if available.

seuser

string

The user part of the SELinux filesystem object context.

By default it uses the system policy, where applicable.

When set to _default, it will use the user portion of the policy if available.

src

path / required

An already existing directory full of source files.

unsafe_writes

boolean

added in 2.2 of ansible.builtin

Influence when to use atomic operation to prevent data corruption or inconsistent reads from the target filesystem object.

By default this module uses atomic operations to prevent data corruption or inconsistent reads from the target filesystem objects, but sometimes systems are configured or just broken in ways that prevent this. One example is docker mounted filesystem objects, which cannot be updated atomically from inside the container and can only be written in an unsafe manner.

This option allows Ansible to fall back to unsafe methods of updating filesystem objects when atomic operations fail (however, it doesn’t force Ansible to perform unsafe writes).

IMPORTANT! Unsafe writes are subject to race conditions and can lead to data corruption.

Choices:

  • no ← (default)

  • yes

validate

string

added in 2.0 of ansible.builtin

The validation command to run before copying into place.

The path to the file to validate is passed in via ‘%s’ which must be present as in the sshd example below.

The command is passed securely so shell features like expansion and pipes won’t work.

Attributes

Attribute

Support

Description

action

Support: full

Indicates this has a corresponding action plugin so some parts of the options can be executed on the controller

async

Support: none

Supports being used with the async keyword

bypass_host_loop

Support: none

Forces a ‘global’ task that does not execute per host, this bypasses per host templating and serial, throttle and other loop considerations

Conditionals will work as if run_once is being used, variables used will be from the first available host

This action will not work normally outside of lockstep strategies

check_mode

Support: none

Can run in check_mode and return changed status prediction without modifying target

diff_mode

Support: full

Will return details on what has changed (or possibly needs changing in check_mode), when in diff mode

platform

Platform: posix

Target OS/families that can be operated against

safe_file_operations

Support: full

Uses Ansbile’s strict file operation functions to ensure proper permissions and avoid data corruption

vault

Support: full

added in 2.2 of ansible.builtin

Can automatically decrypt Ansible vaulted files

See Also

See also

ansible.builtin.copy

The official documentation on the ansible.builtin.copy module.

ansible.builtin.template

The official documentation on the ansible.builtin.template module.

ansible.windows.win_copy

The official documentation on the ansible.windows.win_copy module.

Examples

- name: Assemble from fragments from a directory
  ansible.builtin.assemble:
    src: /etc/someapp/fragments
    dest: /etc/someapp/someapp.conf

- name: Insert the provided delimiter between fragments
  ansible.builtin.assemble:
    src: /etc/someapp/fragments
    dest: /etc/someapp/someapp.conf
    delimiter: '### START FRAGMENT ###'

- name: Assemble a new "sshd_config" file into place, after passing validation with sshd
  ansible.builtin.assemble:
    src: /etc/ssh/conf.d/
    dest: /etc/ssh/sshd_config
    validate: /usr/sbin/sshd -t -f %s

Authors

  • Stephen Fromm (@sfromm)