community.docker.docker_container_exec module – Execute command in a docker container

Note

This module is part of the community.docker collection (version 3.2.1).

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_container_exec.

New in community.docker 1.5.0

Synopsis

  • Executes a command in a Docker container.

Requirements

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

  • Docker API >= 1.25

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

  • paramiko (when using SSH with use_ssh_client=false)

  • pyOpenSSL (when using TLS)

  • pywin32 (when using named pipes on Windows 32)

  • requests

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 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"

argv

list / elements=string

The command to execute.

Since this is a list of arguments, no quoting is needed.

Exactly one of argv and command must be specified.

ca_cert

aliases: 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.

chdir

string

The directory to run the command in.

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.

command

string

The command to execute.

Exactly one of argv and command must be specified.

container

string / required

The name of the container to execute the command in.

debug

boolean

Debug mode

Choices:

  • false ← (default)

  • true

detach

boolean

added in community.docker 2.1.0

Whether to run the command synchronously (detach=false, default) or asynchronously (detach=true).

If set to true, stdin cannot be provided, and the return values stdout, stderr and rc are not returned.

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"

env

dictionary

added in community.docker 2.1.0

Dictionary of environment variables with their respective values to be passed to the command ran inside the container.

Values which might be parsed as numbers, booleans or other types by the YAML parser must be quoted (for example "true") in order to avoid data loss.

Please note that if you are passing values in with Jinja2 templates, like "{{ value }}", you need to add | string to prevent Ansible to convert strings such as "true" back to booleans. The correct way is to use "{{ value | string }}".

ssl_version

string

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

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

stdin

string

Set the stdin of the command directly to the specified value.

Can only be used if detach=false.

stdin_add_newline

boolean

If set to true, appends a newline to stdin.

Choices:

  • false

  • true ← (default)

strip_empty_ends

boolean

Strip empty lines from the end of stdout/stderr in result.

Choices:

  • false

  • true ← (default)

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.

tty

boolean

Whether to allocate a TTY.

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.

Choices:

  • false ← (default)

  • true

user

string

If specified, the user to execute this command with.

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

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: none

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

diff_mode

Support: none

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

Notes

Note

  • Does not support check_mode.

  • 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_SSL_VERSION, 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.

  • This module does not use the Docker SDK for Python to communicate with the Docker daemon. It uses code derived from the Docker SDK or Python that is included in this collection.

Examples

- name: Run a simple command (command)
  community.docker.docker_container_exec:
    container: foo
    command: /bin/bash -c "ls -lah"
    chdir: /root
  register: result

- name: Print stdout
  debug:
    var: result.stdout

- name: Run a simple command (argv)
  community.docker.docker_container_exec:
    container: foo
    argv:
      - /bin/bash
      - "-c"
      - "ls -lah > /dev/stderr"
    chdir: /root
  register: result

- name: Print stderr lines
  debug:
    var: result.stderr_lines

Return Values

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

Key

Description

exec_id

string

added in community.docker 2.1.0

The execution ID of the command.

Returned: success and detach=true

Sample: "249d9e3075655baf705ed8f40488c5e9434049cf3431976f1bfdb73741c574c5"

rc

integer

The exit code of the command.

Returned: success and detach=false

Sample: 0

stderr

string

The standard error output of the container command.

Returned: success and detach=false

stdout

string

The standard output of the container command.

Returned: success and detach=false

Authors

  • Felix Fontein (@felixfontein)