如何在ansible中使用jinja2模板创建一个包含多个条目的json文件？

Question

I am trying to create a json file with multiple secret (dictionary) and storage class. But the template is created in such a way that it will create multiple json file with single secret and a storage class in each file.

my template (resources.j2) is look below

    "secret": [
    {
      "name": "secret{{ user_name }}",
      "label": "{{ user_name }}",
      "backend": "{{ local_array_ip }}",
      "username": "{{ user_name }}",
      "password": "{{password | default('test123')}}",
      "namespace": "{{ default_namespace }}"
    }
  ],
  "storageclass": [
    {
      "name": "sc{{ user_name }}",
      "secret": "{{ user_name }}",
      "label": "sc-{{ user_name }}",
      "limitMbps": "800",
      "fstype": "xfs",
      "accessProtocol": "{{ protocol }}"
    }
  ]
}

I am creating json inside a library file which is called in loop

- name: Create config files for mulitple users
    include: lib/create_config_for_multiple_users.yaml
    vars:
      user_name: "{{ userName }}{{iterationCount}}"          
    with_sequence: count="5"
    loop_control:
      loop_var: iterationCount

In the Create_config_for_multiple_users.yml , it is creating json file for each user (so totally 5 json files are getting created). Creation of json file from template is given below.

- set_fact:
     tmp_dynamic_json_file: "/tmp/temp-json-{{User}}-{{ lookup('pipe', 'date +%Y-%m-%d-%H-%M-%s') }}.json"


- name: Create dynamic Json file with user
  template:
    dest: "{{tmp_dynamic_json_file}}"
    src: "resources.j2"
  delegate_to: localhost

Actually i wanted one single json file with multiple entries like below.

"secret": [
        {
          "name": "secrettest1",
          "label": "test1",
          "backend": "{{ local_array_ip }}",
          "username": "test1",
          "password": "test123",
          "namespace": "kube-system"
        },
        {
          "name": "secrettest2",
          "label": "test2",
          "backend": "{{ local_array_ip }}",
          "username": "test2",
          "password": "test123",
          "namespace": "kube-system"
        }
      ],
      "storageclass": [
        {
          "name": "sctest1",
          "secret": "test1",
          "label": "sc-test1",
          "limitMbps": "800",
          "fstype": "xfs",
          "accessProtocol": "iscsi"
        },
        {
          "name": "sctest2",
          "secret": "test2",
          "label": "sc-test2",
          "limitMbps": "800",
          "fstype": "xfs",
          "accessProtocol": "iscsi"
        }    
      ]
    }

I don't know how to create template in such a way that it will create only one json.

Answer 1

You are including create_config_for_multiple_users.yaml tasks which effectively iterates over the template: task. If the template task runs multiple times, it creates multiple templates. The iteration in this case, should be within the template. The template task should be only used/invoked once.

Please see the example playbook below. I am including a task file as you do, but it doesn't matter.

  vars:
    userName: 'test'
    local_array_ip: '192.168.1.1'
    default_namespace: 'kube-system'
    protocol: 'iscsi'

  tasks:
  - name: Create config files for mulitple users
    include: create_config.yml

Then in my create_config.yml , I use the template module:

- name: Create dynamic Json file with user
  template:
    dest: '/tmp/resources.json'
    src: 'resources.json.j2'

Then comes the iteration for user numbers in the template resources.json.j2 :

{    
  "secret": [
{% for user_num in range(1, 6) %}
    {
      "name": "secret{{ userName }}{{ user_num }}",
      "label": "{{ userName }}{{ user_num }}",
      "backend": "{{ local_array_ip }}",
      "username": "{{ userName }}{{ user_num }}",
      "password": "{{ password | default('test123') }}",
      "namespace": "{{ default_namespace }}"
    }{% if user_num < 5 %},{% endif %}
      
{% endfor %}
    ],
  "storageclass": [ 
{% for user_num in range(1, 6) %}
    {
      "name": "sc{{ userName }}{{ user_num }}",
      "secret": "{{ userName }}{{ user_num }}",
      "label": "sc-{{ userName }}{{ user_num }}",
      "limitMbps": "800",
      "fstype": "xfs",
      "accessProtocol": "{{ protocol }}"
    }{% if user_num < 5 %},{% endif %}
    
{% endfor %}
  ]
}

I am creating a destination JSON file with a simple name /tmp/resources.json (abridged).

{    
  "secret": [
    {
      "name": "secrettest1",
      "label": "test1",
      "backend": "192.168.1.1",
      "username": "test1",
      "password": "test123",
      "namespace": "kube-system"
    },      
    {
      "name": "secrettest2",
      "label": "test2",
      "backend": "192.168.1.1",
      "username": "test2",
      "password": "test123",
     "namespace": "kube-system"
    },      
  "storageclass": [ 
    {
      "name": "sctest1",
      "secret": "test1",
      "label": "sc-test1",
      "limitMbps": "800",
      "fstype": "xfs",
      "accessProtocol": "iscsi"
    },    
    {
      "name": "sctest2",
      "secret": "test2",
      "label": "sc-test2",
      "limitMbps": "800",
      "fstype": "xfs",
      "accessProtocol": "iscsi"
    },