# python.d.plugin `python.d.plugin` is a Netdata external plugin. It is an **orchestrator** for data collection modules written in `python`. 1. It runs as an independent process `ps fax` shows it 2. It is started and stopped automatically by Netdata 3. It communicates with Netdata via a unidirectional pipe (sending data to the `netdata` daemon) 4. Supports any number of data collection **modules** 5. Allows each **module** to have one or more data collection **jobs** 6. Each **job** is collecting one or more metrics from a single data source ## Disclaimer All third party libraries should be installed system-wide or in `python_modules` directory. Module configurations are written in YAML and **pyYAML is required**. Every configuration file must have one of two formats: - Configuration for only one job: ```yaml update_every : 2 # update frequency priority : 20000 # where it is shown on dashboard other_var1 : bla # variables passed to module other_var2 : alb ``` - Configuration for many jobs (ex. mysql): ```yaml # module defaults: update_every : 2 priority : 20000 local: # job name update_every : 5 # job update frequency other_var1 : some_val # module specific variable other_job: priority : 5 # job position on dashboard other_var2 : val # module specific variable ``` `update_every` and `priority` are always optional. ## How to debug a python module ``` # become user netdata sudo su -s /bin/bash netdata ``` Depending on where Netdata was installed, execute one of the following commands to trace the execution of a python module: ``` # execute the plugin in debug mode, for a specific module /opt/netdata/usr/libexec/netdata/plugins.d/python.d.plugin debug trace /usr/libexec/netdata/plugins.d/python.d.plugin debug trace ``` Where `[module]` is the directory name under **Note**: If you would like execute a collector in debug mode while it is still running by Netdata, you can pass the `nolock` CLI option to the above commands. ## How to write a new module See [develop a custom collector in Python](https://github.com/netdata/netdata/edit/master/docs/guides/python-collector.md).