博客

1. exists和not exists

exists：

[root@server4 pd]# cat pd3.yml 
---
- hosts: testB
  remote_user: root
  gather_facts: no
  vars:
    testpath: /testdir
  tasks:
  - debug:
      msg: "file exist"
    when: testpath is exists

测试：

[root@server4 pd]# ansible-playbook pd3.yml 

PLAY [testB] *******************************************************************

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "file exist"
}

not exists：


格式1：

[root@server4 pd]# cat pd3.yml 
---
- hosts: testB
  remote_user: root
  gather_facts: no
  vars:
    testpath: /testdirhs
  tasks:
  - debug:
      msg: "file  is not exist"
when: testpath is not exists
格式2：
[root@server4 pd]# cat pd3.yml 
---
- hosts: testB
  remote_user: root
  gather_facts: no
  vars:
    testpath: /testdirhs
  tasks:
  - debug:
      msg: "file  is not exist"
    when: not testpath is exists

测试：

[root@server4 pd]# ansible-playbook pd3.yml 

PLAY [testB] *******************************************************************

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "file  is not exist"
}

2. defined、undefined、none

[root@server4 pd]# cat pd4.yml 
---
- hosts: testB
  remote_user: root
  gather_facts: no
  vars:
    testvar: "test"
    testvar1:
  tasks:
  - debug:
      msg: "variable is defined"
    when: testvar is defined
  - debug:
      msg: "variable is undefined"
    when: testvar2 is undefined
  - debug:
      msg: "the variable is defined,but is no value"
    when: testvar1 is none

测试：

[root@server4 pd]# ansible-playbook pd4.yml 

PLAY [testB] *******************************************************************

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "variable is defined"
}

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "variable is undefined"
}

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "the variable is defined,but is no value"
}

3. success、failure、change、skip

[root@server4 pd]# cat pd5.yml 
---
- hosts: testB
  remote_user: root
  gather_facts: no
  vars:
    doshell: "yes"
  tasks:
  - shell: "cat /testdir/abc"
    when: doshell == "yes"
    register: returnmsg
    ignore_errors: true
  - debug:
      msg: "success"
    when: returnmsg is success
  - debug:
      msg: "failure"
    when: returnmsg is failure
  - debug:
      msg: "change"
    when: returnmsg is change
  - debug:
      msg: "skip"
    when: returnmsg is skip

测试：

[root@server4 pd]# ansible-playbook pd5.yml 

PLAY [testB] *******************************************************************

TASK [shell] *******************************************************************
fatal: [172.25.60.3]: FAILED! => {"ansible_facts": {"discovered_interpreter_python": "/usr/bin/python"}, "changed": true, "cmd": "cat /testdir/abc", "delta": "0:00:00.002901", "end": "2020-03-29 12:45:36.067104", "msg": "non-zero return code", "rc": 1, "start": "2020-03-29 12:45:36.064203", "stderr": "cat: /testdir/abc: No such file or directory", "stderr_lines": ["cat: /testdir/abc: No such file or directory"], "stdout": "", "stdout_lines": []}
...ignoring

TASK [debug] *******************************************************************
skipping: [172.25.60.3]

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "failure"
}

TASK [debug] *******************************************************************
ok: [172.25.60.3] => {
    "msg": "change"
}

TASK [debug] *******************************************************************
skipping: [172.25.60.3]