kubernetes.core.k8s_exec – Execute command in Pod

Note

This plugin is part of the kubernetes.core collection (version 2.2.2).

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 >= 3.6

  • kubernetes >= 12.0.0

  • PyYAML >= 3.11

Parameters

Parameter Choices/Defaults Comments
api_key
string
Token used to authenticate with the API. Can also be specified via K8S_AUTH_API_KEY environment variable.
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.

aliases: ssl_ca_cert
client_cert
path
Path to a certificate used to authenticate with the API. Can also be specified via K8S_AUTH_CERT_FILE environment variable.

aliases: cert_file
client_key
path
Path to a key file used to authenticate with the API. Can also be specified via K8S_AUTH_KEY_FILE environment variable.

aliases: key_file
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
raw
Path to an existing Kubernetes config file. If not provided, and no other connection options are provided, the Kubernetes client will attempt to load the default configuration file from ~/.kube/config. Can also be specified via K8S_AUTH_KUBECONFIG environment variable.
The kubernetes configuration can be provided as dictionary. This feature requires a python kubernetes client version >= 17.17.0. Added in version 2.2.0.
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
    Choices:
  • no
  • yes
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
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).
proxy_headers
dictionary
added in 2.0.0 of kubernetes.core
The Header used for the HTTP proxy.
basic_auth
string
Colon-separated username:password for basic authentication header.
Can also be specified via K8S_AUTH_PROXY_HEADERS_BASIC_AUTH environment.
proxy_basic_auth
string
Colon-separated username:password for proxy basic authentication header.
Can also be specified via K8S_AUTH_PROXY_HEADERS_PROXY_BASIC_AUTH environment.
user_agent
string
String representing the user-agent you want, such as foo/1.0.
Can also be specified via K8S_AUTH_PROXY_HEADERS_USER_AGENT environment.
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 community.okd.k8s_auth module, as that might do what you need.
validate_certs
boolean
    Choices:
  • no
  • yes
Whether or not to verify the API server's SSL certificates. Can also be specified via K8S_AUTH_VERIFY_SSL environment variable.

aliases: verify_ssl

Notes

Note

  • Return code rc for the command executed is added in output in version 2.2.0, and deprecates return code return_code.

  • 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.

  • 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.rc != 0

Return Values

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

Key Returned Description
result
complex
success
The command object

 
rc
integer
added in 2.2.0 of kubernetes.core
success
The command status code

 
return_code
integer
success
The command status code. This attribute is deprecated and will be removed in a future release. Please use rc instead.

 
stderr
string
success
The command stderr

 
stderr_lines
string
success
The command stderr

 
stdout
string
success
The command stdout

 
stdout_lines
string
success
The command stdout



Authors

  • Tristan de Cacqueray (@tristanC)