在开发模块之前,现问下自己几个问题?
- 官方是否有提供的类似功能模块? 可从下面两个连接确定官方提供的模块,以免重复造轮子 官方已发布的模块 http://docs.ansible.com/ansible/modules.html 官方正在开发的模块 https://github.com/ansible/ansible/labels/module
- 你需要开发一个action 插件么? action插件是在ansible主机上运行,而不是在目标主机上运行的。对于类似file/copy/template功能的模块,在模块执行前需要在ansible主机上做一些操作的。有关action插件的开发请移步到
明确几点
- 模块是传送到目标主机上运行的。
- 模块的返回值必须是json dumps的字符串。
执行模块的过程
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。
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
模块工具
Ansible提供了许多模块实用程序,它们提供了在开发自己的模块时可以使用的辅助功能。 basic.py模块为程序提供访问Ansible库的主要入口点,所有Ansible模块必须至少从basic.py导入:
from ansible.module_utils.basic import *
其他模块工具 a10.py - Utilities used by the a10_server module to manage A10 Networks devices. api.py - Adds shared support for generic API modules. aos.py - Module support utilities for managing Apstra AOS Server. asa.py - Module support utilities for managing Cisco ASA network devices. azure_rm_common.py - Definitions and utilities for Microsoft Azure Resource Manager template deployments. basic.py - General definitions and helper utilities for Ansible modules. cloudstack.py - Utilities for CloudStack modules. database.py - Miscellaneous helper functions for PostGRES and MySQL docker_common.py - Definitions and helper utilities for modules working with Docker. ec2.py - Definitions and utilities for modules working with Amazon EC2 eos.py - Helper functions for modules working with EOS networking devices. f5.py - Helper functions for modules working with F5 networking devices. facts.py - Helper functions for modules that return facts. gce.py - Definitions and helper functions for modules that work with Google Compute Engine resources. ios.py - Definitions and helper functions for modules that manage Cisco IOS networking devices iosxr.py - Definitions and helper functions for modules that manage Cisco IOS-XR networking devices ismount.py - Contains single helper function that fixes os.path.ismount junos.py - Definitions and helper functions for modules that manage Junos networking devices known_hosts.py - utilities for working with known_hosts file mysql.py - Allows modules to connect to a MySQL instance netapp.py - Functions and utilities for modules that work with the NetApp storage platforms. netcfg.py - Configuration utility functions for use by networking modules netcmd.py - Defines commands and comparison operators for use in networking modules network.py - Functions for running commands on networking devices nxos.py - Contains definitions and helper functions specific to Cisco NXOS networking devices openstack.py - Utilities for modules that work with Openstack instances. openswitch.py - Definitions and helper functions for modules that manage OpenSwitch devices powershell.ps1 - Utilities for working with Microsoft Windows clients pycompat24.py - Exception workaround for Python 2.4. rax.py - Definitions and helper functions for modules that work with Rackspace resources. redhat.py - Functions for modules that manage Red Hat Network registration and subscriptions service.py - Contains utilities to enable modules to work with Linux services (placeholder, not in use). shell.py - Functions to allow modules to create shells and work with shell commands six/init.py - Bundled copy of the Six Python library to aid in writing code compatible with both Python 2 and Python 3. splitter.py - String splitting and manipulation utilities for working with Jinja2 templates urls.py - Utilities for working with http and https requests vca.py - Contains utilities for modules that work with VMware vCloud Air vmware.py - Contains utilities for modules that work with VMware vSphere VMs vyos.py - Definitions and functions for working with VyOS networking