k8s_cp doesn't work correctly when deployed container's WORKDIR is other than '/'

[itaru2622]

SUMMARY

k8s_cp doesn't work correctly when k8s container deployed with WORKDIR other than '/'.
on uploading( state:to_pod ), k8s_cp copies to ${WORKDIR}/${remote_path} but not ${remote_path} even given remote_path is full path ('/tmp/...')

some docker image sets WORKDIR(workingDir in k8s) other than '/' , like official golang image sets to /go,
then, k8s_cp cannot work with such container.

ISSUE TYPE

• Bug Report

COMPONENT NAME

not sure but may be somewhere kubernetes.core.k8s_cp to
https://github.com/kubernetesclient/python/blob/master/kubernetes/client/api/core_v1_api.py

ANSIBLE VERSION

# ansible --version
ansible [core 2.11.4] 
  config file = None
  configured module search path = ['/root/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.9/dist-packages/ansible
  ansible collection location = /root/.ansible/collections:/usr/share/ansible/collections
  executable location = /usr/local/bin/ansible
  python version = 3.9.2 (default, Feb 28 2021, 17:03:44) [GCC 10.2.1 20210110]
  jinja version = 3.0.1
  libyaml = True

COLLECTION VERSION

I install kubernetes.core with latest github main branch

ansible-galaxy collection list kubernetes.core
# /root/.ansible/collections/ansible_collections
Collection      Version
--------------- -------
kubernetes.core 2.1.1  

# /usr/local/lib/python3.9/dist-packages/ansible_collections
Collection      Version
--------------- -------
kubernetes.core 1.2.1  

CONFIGURATION

# ansible-config dump --only-changed

OS / ENVIRONMENT

debian:bullseye

STEPS TO REPRODUCE

• install latest kubernetes.core by
  ansible-galaxy collection install git+https://github.com/ansible-collections/kubernetes.core.git

• deploy container on k8s with "workingDir:/otherthanRoot" (official golang image is easy to test)

• k8s_cp with {local_path: /tmp/any.txt, remote_path: /tmp/any.txt, state: to_pod }

• k8s_cp returns without error.

• login the container shell with "kubectl exec ...", and check if /tmp/any.txt is exist.
  => file is uploaded in wrong path, ${workingDir}/tmp/any.txt but not /tmp/any.txt

• official golang image set WORK_DIR as /go so, it cannot upload to golang based container.

Following are my test codes.
ansible-playbook -i hosts -e test=alpine:latest
=> when workindDir is '/home' => failed always (uploaded in wrong path, even official alpine nor debian)
=> if workingDir is '/', => succeeded (official golang as well)
=> if workingDir is undefined => depends on images's WORKDIR (may '/', '/go', ...)

- name: bootstrap ansible test
  hosts: localhost
  gather_facts: no
  connection: local
  tasks:
   - ...
---
- name: setup
  block:
  - set_fact:
      images: [ "alpine:latest", "golang:alpine", "debian:bullseye", "golang:bullseye" ]
#     workingDir: "/"
      workingDir: "/home"
      kubeconfig: "/root/.kube/config"
      cases: "{{ [] }}"
  - set_fact:
      cases: |
        {{ cases + [{  'image': item , 'container': item|replace(':','-')|replace('/','-')|replace('.','')  }] }}
    with_items: "{{ images }}"
    
  - template:
      src: "pod-template.j2"
      dest: "/tmp/pod-sample.yaml"
  - k8s:
      state: present
      src: "/tmp/pod-sample.yaml"
      kubeconfig: "{{ kubeconfig }}"

  - name: wait pod ready (this doesn't work in some cases...)
    command: |
       kubectl wait pod --for=condition=ready --kubeconfig {{kubeconfig}} sample-0 --timeout=150s

  - name: prepare content
    copy:
      dest: "/tmp/{{item}}.sh"
      content: |
         #!/bin/sh
         echo "{{item}}" > /tmp/{{item}}.txt
         date            >> /tmp/{{item}}.txt
      mode: +x
    with_items: "{{ cases | map(attribute='container')| list }}"

- name: "test : {{ test }}"
  set_fact:
    target: "{{ test |replace(':','-')|replace('/','-')| replace('.','') }}"

- name: test  {{ target }}
  block:
    - include_tasks: "k8s-test.yaml"
      vars:
        container: "{{ target }}"
        namespace:  "default"
        pod:        "sample-0"
        shell:      "/bin/sh -c"
        upload: { 'local_path': "/tmp/{{target}}.sh", 'remote_path':"/tmp/{{target}}1.sh" }
        exec: |
           rm -f /tmp/{{target}}.txt
           /tmp/{{target}}1.sh
        download: { 'remote_path': "/tmp/{{target}}.txt", 'local_path': "/tmp/{{target}}1.txt" }
    - debug:
        msg: "got: {{ lookup('file', '/tmp/{{target}}1.txt') }}"
---
# k8s-test.yaml

#- name: set target container on k8s
# set_fact:
#    namespace: "default"
#    pod:       "sample"
#    shell:     "/bin/sh -c"
#    container: "alpine-latest"

- name: "uploading     x       core.k8s_cp"
  when: upload is defined
  kubernetes.core.k8s_cp:
    state:         to_pod 
    kubeconfig:    "{{ kubeconfig }}"
    namespace:     "{{ namespace }}"
    pod:           "{{ pod }}"
    container:     "{{ container }}"
    local_path:    "{{ upload.local_path }}"
    remote_path:   "{{ upload.remote_path }}"

- name: "exec          x       core.k8s_exec"
  when: exec is defined
  kubernetes.core.k8s_exec:
     kubeconfig:   "{{ kubeconfig }}"
     namespace:    "{{ namespace }}"
     pod:          "{{ pod }}"
     container:    "{{ container }}"
     command: >-
        {{shell}} '{{ exec }}'
  register: result

- name: "result of remote exection"
  debug:
    var: result

- name: "downloading   x       core.k8s_cp"
  when: download is defined
  kubernetes.core.k8s_cp:
     state: from_pod
     kubeconfig:   "{{ kubeconfig }}"
     namespace:    "{{ namespace }}"
     pod:          "{{ pod }}"
     container:    "{{ container }}"
     remote_path:  "{{ download.remote_path }}"
     local_path:   "{{ download.local_path }}"
---
# pod-template.j2
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: "sample"
  namespace: "default"
spec:
  selector:
    matchLabels:
      k8s-app: "sample"
  serviceName: "sample"
  replicas: 1
  template:
    metadata:
      labels:
        k8s-app: "sample"
    spec:
      containers:
{% for node in cases %}
      - name: {{ node.container }}
        image: {{ node.image }}
        imagePullPolicy: IfNotPresent
{%   if workingDir is defined %}
        workingDir: {{ workingDir }}
{%   endif %}
        command:
          - sh
          - "-c"
          - |
            tail -f /dev/null
{% endfor %}

EXPECTED RESULTS

if path (remote_path or local_path) is started with '/' (i.e. full path),
then k8s_cp should upload/download to the given path but not other place ( ${workingDir}/* )

ACTUAL RESULTS

k8s_cp upload files under ${workingDir}/tmp/... even remote_file is specified to /tmp/...

[itaru2622]

to maintainers,
I investigated some about this issue and found that:

• k8s_cp just calls REST API of /api/v1/namespaces/{namespace}/pods/{name}/execusing via connect_get_namespaced_pod_exec in kubernetes.client.api.core_v1_api

• there is no param to change directory before executing command in the above REST API.

• fortunately, tar command (which k8s_cp using) has special option '-C /changeDirectoryBeforeExection'.
  so appending '-C /' may be easiest way when full path specified.

[abikouo]

Hi @itaru2622

Thanks for taking the time to report this issue and provide full details to reproduce.
Thanks also for the pull request, we will take some time to review it.