community.docker.docker_swarm_info module – Retrieves facts about Docker Swarm cluster.

Note

This module is part of the community.docker collection (version 4.1.0).

You might already have this collection installed if you are using the ansible package. It is not included in ansible-core. To check whether it is installed, run ansible-galaxy collection list.

To install it, use: ansible-galaxy collection install community.docker. You need further requirements to be able to use this module, see Requirements for details.

To use it in a playbook, specify: community.docker.docker_swarm_info.

Synopsis

  • Retrieves facts about a Docker Swarm.

  • Returns lists of swarm objects names for the services - nodes, services, tasks.

  • The output differs depending on API version available on docker host.

  • Must be run on Swarm Manager node; otherwise module fails with error message. It does return boolean flags in on both error and success which indicate whether the docker daemon can be communicated with, whether it is in Swarm mode, and whether it is a Swarm Manager node.

Requirements

The below requirements are needed on the host that executes this module.

  • Docker API >= 1.25

  • Docker SDK for Python: Please note that the docker-py Python module has been superseded by docker (see here for details). Note that both modules should *not* be installed at the same time. Also note that when both modules are installed and one of them is uninstalled, the other might no longer function and a reinstall of it is required.

  • Docker SDK for Python >= 1.10.0

Parameters

Parameter

Comments

api_version

aliases: docker_api_version

string

The version of the Docker API running on the Docker Host.

Defaults to the latest version of the API supported by Docker SDK for Python and the docker daemon.

If the value is not specified in the task, the value of environment variable DOCKER_API_VERSION will be used instead. If the environment variable is not set, the default value will be used.

Default: "auto"

ca_path

aliases: ca_cert, tls_ca_cert, cacert_path

path

Use a CA certificate when performing server verification by providing the path to a CA certificate file.

If the value is not specified in the task and the environment variable DOCKER_CERT_PATH is set, the file ca.pem from the directory specified in the environment variable DOCKER_CERT_PATH will be used.

This option was called ca_cert and got renamed to ca_path in community.docker 3.6.0. The old name has been added as an alias and can still be used.

client_cert

aliases: tls_client_cert, cert_path

path

Path to the client’s TLS certificate file.

If the value is not specified in the task and the environment variable DOCKER_CERT_PATH is set, the file cert.pem from the directory specified in the environment variable DOCKER_CERT_PATH will be used.

client_key

aliases: tls_client_key, key_path

path

Path to the client’s TLS key file.

If the value is not specified in the task and the environment variable DOCKER_CERT_PATH is set, the file key.pem from the directory specified in the environment variable DOCKER_CERT_PATH will be used.

debug

boolean

Debug mode

Choices:

  • false ← (default)

  • true

docker_host

aliases: docker_url

string

The URL or Unix socket path used to connect to the Docker API. To connect to a remote host, provide the TCP connection string. For example, tcp://192.0.2.23:2376. If TLS is used to encrypt the connection, the module will automatically replace tcp in the connection URL with https.

If the value is not specified in the task, the value of environment variable DOCKER_HOST will be used instead. If the environment variable is not set, the default value will be used.

Default: "unix:///var/run/docker.sock"

nodes

boolean

Whether to list swarm nodes.

Choices:

  • false ← (default)

  • true

nodes_filters

dictionary

A dictionary of filter values used for selecting nodes to list.

For example, name: mynode.

See the docker documentation for more information on possible filters.

services

boolean

Whether to list swarm services.

Choices:

  • false ← (default)

  • true

services_filters

dictionary

A dictionary of filter values used for selecting services to list.

For example, name: myservice.

See the docker documentation for more information on possible filters.

tasks

boolean

Whether to list containers.

Choices:

  • false ← (default)

  • true

tasks_filters

dictionary

A dictionary of filter values used for selecting tasks to list.

For example, node: mynode-1.

See the docker documentation for more information on possible filters.

timeout

integer

The maximum amount of time in seconds to wait on a response from the API.

If the value is not specified in the task, the value of environment variable DOCKER_TIMEOUT will be used instead. If the environment variable is not set, the default value will be used.

Default: 60

tls

boolean

Secure the connection to the API by using TLS without verifying the authenticity of the Docker host server. Note that if validate_certs is set to true as well, it will take precedence.

If the value is not specified in the task, the value of environment variable DOCKER_TLS will be used instead. If the environment variable is not set, the default value will be used.

Choices:

  • false ← (default)

  • true

tls_hostname

string

When verifying the authenticity of the Docker Host server, provide the expected name of the server.

If the value is not specified in the task, the value of environment variable DOCKER_TLS_HOSTNAME will be used instead. If the environment variable is not set, the default value will be used.

Note that this option had a default value localhost in older versions. It was removed in community.docker 3.0.0.

Note: this option is no longer supported for Docker SDK for Python 7.0.0+. Specifying it with Docker SDK for Python 7.0.0 or newer will lead to an error.

unlock_key

boolean

Whether to retrieve the swarm unlock key.

Choices:

  • false ← (default)

  • true

use_ssh_client

boolean

added in community.docker 1.5.0

For SSH transports, use the ssh CLI tool instead of paramiko.

Requires Docker SDK for Python 4.4.0 or newer.

Choices:

  • false ← (default)

  • true

validate_certs

aliases: tls_verify

boolean

Secure the connection to the API by using TLS and verifying the authenticity of the Docker host server.

If the value is not specified in the task, the value of environment variable DOCKER_TLS_VERIFY will be used instead. If the environment variable is not set, the default value will be used.

Choices:

  • false ← (default)

  • true

verbose_output

boolean

When set to true and nodes, services, or tasks is set to true, then the module output will contain verbose information about objects matching the full output of API method.

For details see the documentation of your version of Docker API at https://docs.docker.com/engine/api/.

The verbose output in this module contains only subset of information returned by this info module for each type of the objects.

Choices:

  • false ← (default)

  • true

Attributes

Attribute

Support

Description

action_group

Action groups: community.docker.docker, docker

Use group/docker or group/community.docker.docker in module_defaults to set defaults for this module.

check_mode

Support: full

This action does not modify state.

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

diff_mode

Support: N/A

This action does not modify state.

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

Notes

Note

  • Connect to the Docker daemon by providing parameters with each task or by defining environment variables. You can define DOCKER_HOST, DOCKER_TLS_HOSTNAME, DOCKER_API_VERSION, DOCKER_CERT_PATH, DOCKER_TLS, DOCKER_TLS_VERIFY and DOCKER_TIMEOUT. If you are using docker machine, run the script shipped with the product that sets up the environment. It will set these variables for you. See https://docs.docker.com/machine/reference/env/ for more details.

  • When connecting to Docker daemon with TLS, you might need to install additional Python packages. For the Docker SDK for Python, version 2.4 or newer, this can be done by installing docker[tls] with ansible.builtin.pip.

  • Note that the Docker SDK for Python only allows to specify the path to the Docker configuration for very few functions. In general, it will use $HOME/.docker/config.json if the DOCKER_CONFIG environment variable is not specified, and use $DOCKER_CONFIG/config.json otherwise.

  • This module uses the Docker SDK for Python to communicate with the Docker daemon.

Examples

- name: Get info on Docker Swarm
  community.docker.docker_swarm_info:
  ignore_errors: true
  register: result

- name: Inform about basic flags
  ansible.builtin.debug:
    msg: |
      Was able to talk to docker daemon: {{ result.can_talk_to_docker }}
      Docker in Swarm mode: {{ result.docker_swarm_active }}
      This is a Manager node: {{ result.docker_swarm_manager }}

- name: Get info on Docker Swarm and list of registered nodes
  community.docker.docker_swarm_info:
    nodes: true
  register: result

- name: Get info on Docker Swarm and extended list of registered nodes
  community.docker.docker_swarm_info:
    nodes: true
    verbose_output: true
  register: result

- name: Get info on Docker Swarm and filtered list of registered nodes
  community.docker.docker_swarm_info:
    nodes: true
    nodes_filters:
      name: mynode
  register: result

- name: Show swarm facts
  ansible.builtin.debug:
    var: result.swarm_facts

- name: Get the swarm unlock key
  community.docker.docker_swarm_info:
    unlock_key: true
  register: result

- name: Print swarm unlock key
  ansible.builtin.debug:
    var: result.swarm_unlock_key

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key

Description

can_talk_to_docker

boolean

Will be true if the module can talk to the docker daemon.

Returned: both on success and on error

docker_swarm_active

boolean

Will be true if the module can talk to the docker daemon, and the docker daemon is in Swarm mode.

Returned: both on success and on error

docker_swarm_manager

boolean

Will be true if the module can talk to the docker daemon, the docker daemon is in Swarm mode, and the current node is a manager node.

Only if this one is true, the module will not fail.

Returned: both on success and on error

nodes

list / elements=dictionary

List of dict objects containing the basic information about each volume. Keys matches the docker node ls output unless verbose_output=true. See description for verbose_output.

Returned: When nodes=true

services

list / elements=dictionary

List of dict objects containing the basic information about each volume. Keys matches the docker service ls output unless verbose_output=true. See description for verbose_output.

Returned: When services=true

swarm_facts

dictionary

Facts representing the basic state of the docker Swarm cluster.

Contains tokens to connect to the Swarm

Returned: always

swarm_unlock_key

string

Contains the key needed to unlock the swarm.

Returned: When unlock_key=true.

tasks

list / elements=dictionary

List of dict objects containing the basic information about each volume. Keys matches the docker service ps output unless verbose_output=true. See description for verbose_output.

Returned: When tasks=true

Authors

  • Piotr Wojciechowski (@WojciechowskiPiotr)