Ansible 开发¶

官方开发文档¶

http://docs.ansible.com/ansible/dev_guide/index.html

非常推荐大家看看 官方文档

环境¶

本次所用的环境

ansible 2.9.6.0
os Centos 7.7 X64
python 2.7.5

介绍¶

Ansible 开发分为两大模块，一是modules，二是plugins。

首先，要记住这两部分内容在哪个地方执行？

modules 文件被传送到 远端主机 并执行。
plugins 是在 ansible控制节点 上执行的。

再者是执行顺序？

plugins 先于 modules 执行。

然后大家明确这两部分内容是干啥用的？

modules 是ansible的核心内容，它使playbook变得更加简单明了，一个task就是完成某一项功能。ansible模块是被传送到远程主机上运行的。所以它们可以用远程主机可以执行的任何语言编写modules。
plugins 是在 ansible控制节点 上执行的，用来辅助modules做一些操作。比如连接远程主机，拷贝文件到远程主机之类的。

最后，学习开发之前，要先学会Debug

Ad-hoc 执行过程¶

# ansible 192.168.77.130 -m ping -vvv
ansible 2.9.6
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.5 (default, Aug  7 2019, 00:51:29) [GCC 4.8.5 20150623 (Red Hat 4.8.5-39)]
Using /etc/ansible/ansible.cfg as config file
host_list declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
script declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
auto declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
Parsed /etc/ansible/hosts inventory source with ini plugin
META: ran handlers
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'echo ~root && sleep 0'"'"''
<192.168.77.130> (0, '/root\n', '')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'( umask 77 && mkdir -p "` echo /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356 `" && echo ansible-tmp-1586615361.42-9030567083356="` echo /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356 `" ) && sleep 0'"'"''
<192.168.77.130> (0, 'ansible-tmp-1586615361.42-9030567083356=/root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356\n', '')
<192.168.77.130> Attempting python interpreter discovery
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'echo PLATFORM; uname; echo FOUND; command -v '"'"'"'"'"'"'"'"'/usr/bin/python'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.7'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.6'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.5'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python2.7'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python2.6'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'/usr/libexec/platform-python'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'/usr/bin/python3'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python'"'"'"'"'"'"'"'"'; echo ENDFOUND && sleep 0'"'"''
<192.168.77.130> (0, 'PLATFORM\nLinux\nFOUND\n/usr/bin/python\n/usr/bin/python2.7\n/usr/libexec/platform-python\n/usr/bin/python\nENDFOUND\n', '')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'/usr/bin/python && sleep 0'"'"''
<192.168.77.130> (0, '{"osrelease_content": "NAME=\\"CentOS Linux\\"\\nVERSION=\\"7 (Core)\\"\\nID=\\"centos\\"\\nID_LIKE=\\"rhel fedora\\"\\nVERSION_ID=\\"7\\"\\nPRETTY_NAME=\\"CentOS Linux 7 (Core)\\"\\nANSI_COLOR=\\"0;31\\"\\nCPE_NAME=\\"cpe:/o:centos:centos:7\\"\\nHOME_URL=\\"https://www.centos.org/\\"\\nBUG_REPORT_URL=\\"https://bugs.centos.org/\\"\\n\\nCENTOS_MANTISBT_PROJECT=\\"CentOS-7\\"\\nCENTOS_MANTISBT_PROJECT_VERSION=\\"7\\"\\nREDHAT_SUPPORT_PRODUCT=\\"centos\\"\\nREDHAT_SUPPORT_PRODUCT_VERSION=\\"7\\"\\n\\n", "platform_dist_result": ["centos", "7.4.1708", "Core"]}\n', '')
Using module file /usr/lib/python2.7/site-packages/ansible/modules/system/ping.py
<192.168.77.130> PUT /root/.ansible/tmp/ansible-local-50740hJgOb9/tmpp7Dy_u TO /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/AnsiballZ_ping.py
<192.168.77.130> SSH: EXEC sshpass -d8 sftp -o BatchMode=no -b - -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 '[192.168.77.130]'
<192.168.77.130> (0, 'sftp> put /root/.ansible/tmp/ansible-local-50740hJgOb9/tmpp7Dy_u /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/AnsiballZ_ping.py\n', '')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'chmod u+x /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/ /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/AnsiballZ_ping.py && sleep 0'"'"''
<192.168.77.130> (0, '', '')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 -tt 192.168.77.130 '/bin/sh -c '"'"'/usr/bin/python /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/AnsiballZ_ping.py && sleep 0'"'"''
<192.168.77.130> (0, '\r\n{"invocation": {"module_args": {"data": "pong"}}, "ping": "pong"}\r\n', 'Shared connection to 192.168.77.130 closed.\r\n')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'rm -f -r /root/.ansible/tmp/ansible-tmp-1586615361.42-9030567083356/ > /dev/null 2>&1 && sleep 0'"'"''
<192.168.77.130> (0, '', '')
192.168.77.130 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python"
    }, 
    "changed": false, 
    "invocation": {
        "module_args": {
            "data": "pong"
        }
    }, 
    "ping": "pong"
}
META: ran handlers
META: ran handlers

首先，将模块文件读入内存，然后添加传递给模块的参数，最后将模块中所需要的类添加到内存，由zipfile压缩后，再由base64进行编码，写入到模版文件内。

通过默认的连接方式，一般是ssh。ansible通过ssh连接到远程主机，创建临时目录，并关闭连接。然后将打开另外一个ssh连接，将模版文件以sftp方式传送到刚刚创建的临时目录中，写完后关闭连接。然后打开一个ssh连接将任务对象赋予可执行权限，执行成功后关闭连接。

最后，ansible将打开第三个连接来执行模块，并删除临时目录及其所有内容。模块的结果是从标准输出stdout中获取json格式的字符串。ansible将解析和处理此字符串。如果有任务是异步控制执行的，ansible将在模块完成之前关闭第三个连接，并且返回主机后，在规定的时间内检查任务状态，直到模块完成或规定的时间超时。

Note

如果要深入了解执行过程，可以查看更详细的代码执行过程Ansible ad-hoc执行过程

使用了 管道连接 后，与远程主机只有一个连接，命令通过数据流的方式发送执行。

配置方式

vim /etc/ansible/ansible.cfg
pipelining = True

执行过程

# ansible 192.168.77.130 -m ping  -vvv
ansible 2.9.6
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.5 (default, Aug  7 2019, 00:51:29) [GCC 4.8.5 20150623 (Red Hat 4.8.5-39)]
Using /etc/ansible/ansible.cfg as config file
host_list declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
script declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
auto declined parsing /etc/ansible/hosts as it did not pass its verify_file() method
Parsed /etc/ansible/hosts inventory source with ini plugin
META: ran handlers
<192.168.77.130> Attempting python interpreter discovery
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'echo PLATFORM; uname; echo FOUND; command -v '"'"'"'"'"'"'"'"'/usr/bin/python'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.7'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.6'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python3.5'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python2.7'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python2.6'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'/usr/libexec/platform-python'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'/usr/bin/python3'"'"'"'"'"'"'"'"'; command -v '"'"'"'"'"'"'"'"'python'"'"'"'"'"'"'"'"'; echo ENDFOUND && sleep 0'"'"''
<192.168.77.130> (0, 'PLATFORM\nLinux\nFOUND\n/usr/bin/python\n/usr/bin/python2.7\n/usr/libexec/platform-python\n/usr/bin/python\nENDFOUND\n', '')
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'/usr/bin/python && sleep 0'"'"''
<192.168.77.130> (0, '{"osrelease_content": "NAME=\\"CentOS Linux\\"\\nVERSION=\\"7 (Core)\\"\\nID=\\"centos\\"\\nID_LIKE=\\"rhel fedora\\"\\nVERSION_ID=\\"7\\"\\nPRETTY_NAME=\\"CentOS Linux 7 (Core)\\"\\nANSI_COLOR=\\"0;31\\"\\nCPE_NAME=\\"cpe:/o:centos:centos:7\\"\\nHOME_URL=\\"https://www.centos.org/\\"\\nBUG_REPORT_URL=\\"https://bugs.centos.org/\\"\\n\\nCENTOS_MANTISBT_PROJECT=\\"CentOS-7\\"\\nCENTOS_MANTISBT_PROJECT_VERSION=\\"7\\"\\nREDHAT_SUPPORT_PRODUCT=\\"centos\\"\\nREDHAT_SUPPORT_PRODUCT_VERSION=\\"7\\"\\n\\n", "platform_dist_result": ["centos", "7.4.1708", "Core"]}\n', '')
Using module file /usr/lib/python2.7/site-packages/ansible/modules/system/ping.py
Pipelining is enabled.
<192.168.77.130> ESTABLISH SSH CONNECTION FOR USER: root
<192.168.77.130> SSH: EXEC sshpass -d8 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o Port=22 -o 'User="root"' -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/09e16ea432 192.168.77.130 '/bin/sh -c '"'"'/usr/bin/python && sleep 0'"'"''
<192.168.77.130> (0, '\n{"invocation": {"module_args": {"data": "pong"}}, "ping": "pong"}\n', '')
192.168.77.130 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python"
    }, 
    "changed": false, 
    "invocation": {
        "module_args": {
            "data": "pong"
        }
    }, 
    "ping": "pong"
}
META: ran handlers
META: ran handlers

执行完后，会有一个ssh的管道, 下次连接远程主机时，会直接使用这个管道，而不必重新建立连接。

# ps aux | grep [a]nsible
root      50757  0.0  0.3 176416  3424 ?        Ss   22:29   0:00 ssh: /root/.ansible/cp/09e16ea432 [mux]

最后更新: 2020-12-03 08:40:01

Ansible 开发¶

官方开发文档¶

环境¶

介绍¶

Ad-hoc 执行过程¶

评论