kubernetes.core.k8s_exec – Execute command in Pod

Note

This plugin is part of the kubernetes.core collection (version 1.2.1).

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 kubernetes.core.

To use it in a playbook, specify: kubernetes.core.k8s_exec.

New in version 0.10.0: of kubernetes.core

Synopsis

  • Use the Kubernetes Python client to execute command on K8s pods.

Note

This module has a corresponding action plugin.

Requirements

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

  • python >= 2.7

  • openshift == 0.4.3

  • PyYAML >= 3.11

Parameters

Parameter

Comments

api_key

string

Token used to authenticate with the API. Can also be specified via K8S_AUTH_API_KEY environment variable.

ca_cert

aliases: ssl_ca_cert

path

Path to a CA certificate used to authenticate with the API. The full certificate chain must be provided to avoid certificate validation errors. Can also be specified via K8S_AUTH_SSL_CA_CERT environment variable.

client_cert

aliases: cert_file

path

Path to a certificate used to authenticate with the API. Can also be specified via K8S_AUTH_CERT_FILE environment variable.

client_key

aliases: key_file

path

Path to a key file used to authenticate with the API. Can also be specified via K8S_AUTH_KEY_FILE environment variable.

command

string / required

The command to execute

container

string

The name of the container in the pod to connect to.

Defaults to only container if there is only one container in the pod.

context

string

The name of a context found in the config file. Can also be specified via K8S_AUTH_CONTEXT environment variable.

host

string

Provide a URL for accessing the API. Can also be specified via K8S_AUTH_HOST environment variable.

kubeconfig

path

Path to an existing Kubernetes config file. If not provided, and no other connection options are provided, the openshift client will attempt to load the default configuration file from ~/.kube/config.json. Can also be specified via K8S_AUTH_KUBECONFIG environment variable.

namespace

string / required

The pod namespace name

password

string

Provide a password for authenticating with the API. Can also be specified via K8S_AUTH_PASSWORD environment variable.

Please read the description of the username option for a discussion of when this option is applicable.

persist_config

boolean

Whether or not to save the kube config refresh tokens. Can also be specified via K8S_AUTH_PERSIST_CONFIG environment variable.

When the k8s context is using a user credentials with refresh tokens (like oidc or gke/gcloud auth), the token is refreshed by the k8s python client library but not saved by default. So the old refresh token can expire and the next auth might fail. Setting this flag to true will tell the k8s python client to save the new refresh token to the kube config file.

Default to false.

Please note that the current version of the k8s python client library does not support setting this flag to True yet.

The fix for this k8s python library is here: https://github.com/kubernetes-client/python-base/pull/169

Choices:

  • no

  • yes

pod

string / required

The pod name

proxy

string

The URL of an HTTP proxy to use for the connection.

Can also be specified via K8S_AUTH_PROXY environment variable.

Please note that this module does not pick up typical proxy settings from the environment (e.g. HTTP_PROXY).

username

string

Provide a username for authenticating with the API. Can also be specified via K8S_AUTH_USERNAME environment variable.

Please note that this only works with clusters configured to use HTTP Basic Auth. If your cluster has a different form of authentication (e.g. OAuth2 in OpenShift), this option will not work as expected and you should look into the k8s_auth module, as that might do what you need.

validate_certs

aliases: verify_ssl

boolean

Whether or not to verify the API server’s SSL certificates. Can also be specified via K8S_AUTH_VERIFY_SSL environment variable.

Choices:

  • no

  • yes

Notes

Note

  • Return code return_code for the command executed is added in output in version 1.0.0.

  • The authenticated user must have at least read access to the pods resource and write access to the pods/exec resource.

  • The OpenShift Python client wraps the K8s Python client, providing full access to all of the APIS and models available on both platforms. For API version details and additional information visit https://github.com/openshift/openshift-restclient-python

  • To avoid SSL certificate validation errors when validate_certs is True, the full certificate chain for the API server must be provided via ca_cert or in the kubeconfig file.

Examples

- name: Execute a command
  kubernetes.core.k8s_exec:
    namespace: myproject
    pod: zuul-scheduler
    command: zuul-scheduler full-reconfigure

- name: Check RC status of command executed
  kubernetes.core.k8s_exec:
    namespace: myproject
    pod: busybox-test
    command: cmd_with_non_zero_exit_code
  register: command_status
  ignore_errors: True

- name: Check last command status
  debug:
    msg: "cmd failed"
  when: command_status.return_code != 0

Return Values

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

Key

Description

result

complex

The command object

Returned: success

return_code

integer

The command status code

Returned: success

stderr

string

The command stderr

Returned: success

stderr_lines

string

The command stderr

Returned: success

stdout

string

The command stdout

Returned: success

stdout_lines

string

The command stdout

Returned: success

Authors

  • Tristan de Cacqueray (@tristanC)