如何从json输出中读取值

如何解决如何从json输出中读取值

基本上，我需要从 JSON 输出中读取一个值并在后续任务中使用它。所以，我尝试了 with_items、loop，但没有任何效果。

我从注册变量生成的示例 JSON：

   TASK [local_volume_mount : debug Info from device that is parted] **************
   Monday 29 March 2021  21:33:39 +0000 (0:00:02.271)       0:00:02.417 ********** 
   ok: [node1] => {
       "partitioned_device_live_info": {
           "changed": false,"msg": "All items completed","results": [
               {
                   "ansible_loop_var": "item","changed": false,"disk": {
                       "dev": "/dev/nvme2n1","logical_block": 512,"model": "SAMSUNG MZQLW960HMJP-00003","physical_block": 512,"size": 937692504.0,"table": "msdos","unit": "kib"
                   },"failed": false,"invocation": {
                       "module_args": {
                           "align": "optimal","device": "/dev/nvme2n1","flags": null,"label": "msdos","name": null,"number": 1,"part_end": "100%","part_start": "0%","part_type": "primary","state": "present","unit": "KiB"
                       }
                   },"item": [
                       {
                           "device": "/dev/nvme2n1","partitions": [
                               {
                                   "end": "100%","start": "0%","storage_class": "ssd-wkr-services"
                               }
                           ]
                       },{
                           "end": "100%","storage_class": "ssd-wkr-services"
                       }
                   ],"partitions": [
                       {
                           "begin": 1024.0,"end": 937692160.0,"flags": [],"fstype": "","name": "","num": 1,"size": 937691136.0,"unit": "kib"
                       }
                   ],"script": ""
               }
           ]
       }
   }
   

因此，从上面我需要读取 partitions.num 值并在下一个任务中使用它，但是，我不知道该怎么做。

任务：

  - name: THIS IS BEING TESTED
    debug:
      var: "{{ item.partitions }}"
    ignore_errors: no
    #loop: "{{ partitioned_device_live_info.results }}"
    with_items: "{{ partitioned_device_live_info.results }}"

上述任务的输出是

'dict object' has no attribute 'partitions'

我想将该值 item.partitions.num 存储在一个变量中，然后在进一步的任务中使用它。

解决方法

使用 msg 搞定，下面是我的改动

  - name: THIS IS BEING TESTED with MSG and with_items
    debug:
      msg: "{{ item.partitions[0].num }}"
    with_items: "{{ partitioned_device_live_info.results }}"

,

您始终可以对 set facts 使用正则表达式。更多详情stackoverflow

以下是一些用例

- name: Long form task does not
  ansible.builtin.replace:
    path: /etc/hosts
    regexp: '\b(localhost)(\d*)\b'
    replace: '\1\2.localdomain\2 \1\2'

- name: Explicitly specifying positional matched groups in replacement
  ansible.builtin.replace:
    path: /etc/ssh/sshd_config
    regexp: '^(ListenAddress[ ]+)[^\n]+$'
    replace: '\g<1>0.0.0.0'

设置fact

- name: set version in file after replacement
  set_fact:
    version_in_file: "{{ version_deployment_file | regex_search(docker_image_version) }}"

更多详情 - ansible.builtin.replace