Lifecycle management

Provisioning a service

When a user request for the first time a service, an instance is created automatically and set to "pending" state on Squest. Once approved by the administrator, the request is sent to Tower to execute the linked job template.

The executed job, aka the Ansible playbook, need to call back the Squest API in order to attach information (spec) to the pending instance.

Squest provisioning workflow:

sequenceDiagram participant User participant Admin participant Squest participant Tower User->>Squest: Request service Admin->>Squest: Approve Admin->>Squest: Process Squest->>Tower: Process Squest-->>Tower: Check Note right of Tower: Running Tower->>Squest: Instance spec <br> {'uuid': 34, 'name': 'instance_name'} Squest-->>Tower: Check Note right of Tower: Successful Squest->>User: Notify service ready

The playbook will receive a squest extra variable that contains information of to the pending instance linked to the request in addition to all extra variables which come from the survey of the job template.

Example of extra variables sent by Squest:

squest:
  instance:
    id: 1
    name: test
    service: 1
    spec: {}
    state: PROVISIONING
file_name: foo.conf

Specs related to the created instance are important in order to be sent later to a playbook in charge of updating this particular instance.

Sent specs must contain unique IDs that allow to identify precisely the instance. (E.g: uuid of a VMware VM, namespace and cluster_api_url for an Openshift project)

Playbook example

In the example below, we've configured a job template with a survey that ask for a variable named file_name. The playbook will:

• create the resource (the file)
• call Squest api to link spec of the created resource to the instance

- name: Create a file
  hosts: localhost
  connection: local
  gather_facts: false

  vars:
    squest_api_url: "http://192.168.58.128:8000/api/"

  tasks:
    - name: Print the job tempalate survey variable
      debug:
        var: file_name

    - name: Print info sent by Squest
      debug:
        var: squest

    - name: Create a file with the given file_name
      ansible.builtin.file:
        path: "/tmp/{{ file_name }}"
        owner: user
        group: user
        mode: '0644'
        state: touch

    - name: Update spec of the instance via the squest API
      uri:
        url: "{{ squest_api_url }}admin/instance/{{ squest['instance']['id'] }}/" # do not forget the last slash
        user: "admin"
        password: "admin"
        method: PATCH
        body:
          spec:
            file_name: "{{ file_name }}"
        force_basic_auth: yes
        status_code: 200
        body_format: json

Day 2 operations

Day 2 operations are operations that update or delete existing resources.

When a user creates a request for a day 2 operation of a provisioned instance, Squest automatically attach an extra_vars named squest that contains the instance spec sent by the playbook used to provision at first the resource.

The playbook used to update the instance need to use info placed in squest variable to retrieve the real resource that need to be updated or deleted. The update playbook can send a new version of the instance to squest at the end of its process if required.

sequenceDiagram participant User participant Admin participant Squest participant Tower User->>Squest: Request update Admin->>Squest: Approve Admin->>Squest: Process Squest->>Tower: Process - Extra vars:<br> {'squest': {'uuid': 34, 'name': 'instance_name'}} Squest-->>Tower: Check Note right of Tower: Running Tower->>Squest: Instance spec update <br> {'uuid': 34, 'name': 'instance_new_name} Squest-->>Tower: Check Note right of Tower: Successful Squest->>User: Notify service updated

Playbook example

Example of extra vars sent by squest:

squest:
  instance:
    id: 1
    name: test-instance
    service: 1
    spec: 
      file_name: foo.conf
    state: UPDATING
string_to_place_in_file: "this is a string"

In the example below, the update job template survey ask for a string_to_place_in_file variable. The playbook receive as well all information that help to retrieve the resource to update. In this example the resource is the file_name.

- name: Update content of a file
  hosts: localhost
  connection: local
  gather_facts: false

  tasks:
    - name: Print the job tempalate survey variable
      debug:
        var: string_to_place_in_file

    - name: Print info sent by Squest
      debug:
        var: squest

    - name: Add content into the file_name given by squest instance spec
      ansible.builtin.lineinfile :
        path: "/tmp/{{ squest['instance']['spec']['file_name'] }}"
        line: "{{ string_to_place_in_file }}"
        create: yes