1### Plugin 2 3Plugin feature for the log collector is to load a user python functions at runtime by the engine and execute it. 4 5The design infrastructure allows user to extend or call their existing python scripts without needing to expose 6the implementation. This enriches the log collection and mechanize the work flow as per user driven as per 7their requirement, 8 9### Understanding Plugin 10The plugin works like any stand-alone piece of python script or library function. 11 12The main components in plugin infrastructure are: 13 14- plugin directory 15- plugin directive in YAML 16- plugin parser in the collector engine 17 18### Plugin Directory 19Python module script are added or copied to `plugins` directory and the log engine loads these plugins during 20runtime and on demand from the YAML else they are not invoked automatically. 21 22Example: 23``` 24plugins/ 25├── foo_func.py 26├── ssh_execution.py 27└── telnet_execution.py 28 29``` 30 31### Plugin Template Example 32 33plugins/foo_func.py 34``` 35# Sample for documentation plugin 36 37def print_vars(var): 38 print(var) 39 40def return_vars(): 41 return 1 42``` 43 44You can add your own plugin modules to extend further. 45 46Test your plugin: 47``` 48python3 plugins/foo_func.py 49``` 50 51### YAML Syntax 52 53Plugin function without return statement. 54``` 55 - plugin: 56 - plugin_name: plugin.foo_func.print_vars 57 - plugin_args: 58 - "Hello plugin" 59``` 60 61Plugin function with return statement. 62``` 63 - plugin: 64 - plugin_name: return_value = plugin.foo_func.return_vars 65 - plugin_args: 66``` 67 68when the return directive is used by implying "=" , the `return_value` 69can be accessed within the same block by another following plugins 70by using the variable name directly. 71 72Example: 73``` 74 - plugin: 75 - plugin_name: plugin.foo_func.print_vars 76 - plugin_args: 77 - return_value 78``` 79 80To accept multiple return values by using coma "," separated statement 81``` 82 -plugin_name: return_value1,return_value2 = plugin.foo_func.print_vars 83``` 84 85### Plugin execution output for sample 86 87 88``` 89 [PLUGIN-START] 90 Call func: plugin.foo_func.print_vars("Hello plugin") 91 Hello plugin 92 return: None 93 [PLUGIN-END] 94 95 [PLUGIN-START] 96 Call func: plugin.foo_func.return_vars() 97 return: 1 98 [PLUGIN-END] 99``` 100