community.docker.docker_containers inventory – Ansible dynamic inventory plugin for Docker containers

Note

This inventory plugin is part of the community.docker collection (version 3.8.0).

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 inventory plugin, see Requirements for details.

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

New in community.docker 1.1.0

Synopsis

  • Reads inventories from the Docker API.

  • Uses a YAML configuration file that ends with docker.[yml|yaml].

Requirements

The below requirements are needed on the local controller node that executes this inventory.

  • requests

  • pywin32 (when using named pipes on Windows 32)

  • paramiko (when using SSH with use_ssh_client=false)

  • pyOpenSSL (when using TLS)

  • backports.ssl_match_hostname (when using TLS on Python 2)

Parameters

Parameter

Comments

add_legacy_groups

boolean

Add the same groups as the docker inventory script does. These are the following:

<container id>: contains the container of this ID.

<container name>: contains the container that has this name.

<container short id>: contains the containers that have this short ID (first 13 letters of ID).

image_<image name>: contains the containers that have the image <image name>.

stack_<stack name>: contains the containers that belong to the stack <stack name>.

service_<service name>: contains the containers that belong to the service <service name>

<docker_host>: contains the containers which belong to the Docker daemon docker_host. Useful if you run this plugin against multiple Docker daemons.

running: contains all containers that are running.

stopped: contains all containers that are not running.

If this is not set to true, you should use keyed groups to add the containers to groups. See the examples for how to do that.

Choices:

  • false ← (default)

  • true

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 this collection 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.

compose

dictionary

Create vars from jinja2 expressions.

Default: {}

configure_docker_daemon

boolean

added in community.docker 1.8.0

Whether to pass all Docker daemon configuration from the inventory plugin to the connection plugin.

Only used when connection_type=docker-api.

Choices:

  • false

  • true ← (default)

connection_type

string

Which connection type to use the containers.

One way to connect to containers is to use SSH (ssh). For this, the options default_ip and private_ssh_port are used. This requires that a SSH daemon is running inside the containers.

Alternatively, docker-cli selects the community.docker.docker connection plugin, and docker-api (default) selects the community.docker.docker_api connection plugin.

When docker-api is used, all Docker daemon configuration values are passed from the inventory plugin to the connection plugin. This can be controlled with configure_docker_daemon.

Note that the community.docker.docker_api does not work with TCP TLS sockets! See https://github.com/ansible-collections/community.docker/issues/605 for more information.

Choices:

  • "ssh"

  • "docker-cli"

  • "docker-api" ← (default)

debug

boolean

Debug mode

Choices:

  • false ← (default)

  • true

default_ip

string

The IP address to assign to ansible_host when the container’s SSH port is mapped to interface ‘0.0.0.0’.

Only used if connection_type is ssh.

Default: "127.0.0.1"

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"

filters

list / elements=dictionary

added in community.docker 3.5.0

A list of include/exclude filters that allows to select/deselect hosts for this inventory.

Filters are processed sequentially until the first filter where filters[].exclude or filters[].include matches is found. In case filters[].exclude matches, the host is excluded, and in case filters[].include matches, the host is included. In case no filter matches, the host is included.

exclude

string

A Jinja2 condition. If it matches for a host, that host is excluded.

Exactly one of filters[].exclude and filters[].include can be specified.

include

string

A Jinja2 condition. If it matches for a host, that host is included.

Exactly one of filters[].exclude and filters[].include can be specified.

groups

dictionary

Add hosts to group based on Jinja2 conditionals.

Default: {}

keyed_groups

list / elements=dictionary

Add hosts to group based on the values of a variable.

Default: []

default_value

string

added in ansible-core 2.12

The default value when the host variable’s value is an empty string.

This option is mutually exclusive with keyed_groups[].trailing_separator.

key

string

The key from input dictionary used to generate groups

parent_group

string

parent group for keyed group

prefix

string

A keyed group name will start with this prefix

Default: ""

separator

string

separator used to build the keyed group name

Default: "_"

trailing_separator

boolean

added in ansible-core 2.12

Set this option to False to omit the keyed_groups[].separator after the host variable when the value is an empty string.

This option is mutually exclusive with keyed_groups[].default_value.

Choices:

  • false

  • true ← (default)

leading_separator

boolean

added in ansible-core 2.11

Use in conjunction with keyed_groups.

By default, a keyed group that does not have a prefix or a separator provided will have a name that starts with an underscore.

This is because the default prefix is “” and the default separator is “_”.

Set this option to False to omit the leading underscore (or other separator) if no prefix is given.

If the group name is derived from a mapping the separator is still used to concatenate the items.

To not use a separator in the group name at all, set the separator for the keyed group to an empty string instead.

Choices:

  • false

  • true ← (default)

plugin

string / required

The name of this plugin, it should always be set to community.docker.docker_containers for this plugin to recognize it as it’s own.

Choices:

  • "community.docker.docker_containers"

private_ssh_port

integer

The port containers use for SSH.

Only used if connection_type is ssh.

Default: 22

ssl_version

string

Provide a valid SSL version number. Default value determined by SSL Python module.

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

strict

boolean

If yes make invalid entries a fatal error, otherwise skip and continue.

Since it is possible to use facts in the expressions they might not always be available and we ignore those errors by default.

Choices:

  • false ← (default)

  • true

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.

use_extra_vars

boolean

added in ansible-core 2.11

Merge extra vars into the available variables for composition (highest precedence).

Choices:

  • false ← (default)

  • true

Configuration:

use_ssh_client

boolean

added in community.docker 1.5.0

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

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

Toggle to (not) include all available inspection metadata.

Note that all top-level keys will be transformed to the format docker_xxx. For example, HostConfig is converted to docker_hostconfig.

If this is false, these values can only be used during compose, groups, and keyed_groups.

The docker inventory script always added these variables, so for compatibility set this to true.

Choices:

  • false ← (default)

  • true

Notes

Note

Examples

# Minimal example using local Docker daemon
plugin: community.docker.docker_containers
docker_host: unix:///var/run/docker.sock

# Minimal example using remote Docker daemon
plugin: community.docker.docker_containers
docker_host: tcp://my-docker-host:2375

# Example using remote Docker daemon with unverified TLS
plugin: community.docker.docker_containers
docker_host: tcp://my-docker-host:2376
tls: true

# Example using remote Docker daemon with verified TLS and client certificate verification
plugin: community.docker.docker_containers
docker_host: tcp://my-docker-host:2376
validate_certs: true
ca_path: /somewhere/ca.pem
client_key: /somewhere/key.pem
client_cert: /somewhere/cert.pem

# Example using constructed features to create groups
plugin: community.docker.docker_containers
docker_host: tcp://my-docker-host:2375
strict: false
keyed_groups:
  # Add containers with primary network foo to a network_foo group
  - prefix: network
    key: 'docker_hostconfig.NetworkMode'
  # Add Linux hosts to an os_linux group
  - prefix: os
    key: docker_platform

# Example using SSH connection with an explicit fallback for when port 22 has not been
# exported: use container name as ansible_ssh_host and 22 as ansible_ssh_port
plugin: community.docker.docker_containers
connection_type: ssh
compose:
  ansible_ssh_host: ansible_ssh_host | default(docker_name[1:], true)
  ansible_ssh_port: ansible_ssh_port | default(22, true)

# Only consider containers which have a label 'foo', or whose name starts with 'a'
plugin: community.docker.docker_containers
filters:
  # Accept all containers which have a label called 'foo'
  - include: >-
      "foo" in docker_config.Labels
  # Next accept all containers whose inventory_hostname starts with 'a'
  - include: >-
      inventory_hostname.startswith("a")
  # Exclude all containers that didn't match any of the above filters
  - exclude: true

Authors

  • Felix Fontein (@felixfontein)

Hint

Configuration entries for each entry type have a low to high priority order. For example, a variable that is lower in the list will override a variable that is higher up.