matthewdeanmartin

John's Unofficial Dummys' Guide to Writing a Cloud Custodian Extension

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This doco is mostly intended to remind the author how this stuff works, but has now been roaded tested by someone else too.

Before you start you'll need an IDE - I use Intellij with the Python plugin. You'll need to have gone through these

• https://cloudcustodian.io/docs/contribute.html
• https://cloudcustodian.io/docs/developer/index.html#developer

matthewdeanmartin

import ast

import astor  # read more at https://astor.readthedocs.io/en/latest/

parsed = ast.parse(open('source.py').read())

for node in ast.walk(parsed):
    # let's work only on functions & classes definitions
    if not isinstance(node, (ast.FunctionDef, ast.ClassDef, ast.AsyncFunctionDef)):
        continue

matthewdeanmartin

Using fish shell with git bash on windows

To install fish shell on windows the options are:

• Cygwin
• WSL
• MSYS2

Since git bash is based on MSYS2 it seems a good fit to install fish. The problem is that git bash is a lightweight version of MSYS2 which does not include pacman as a package management, used to install fish.

This OS thread has great suggestions on how to solve this problem including using the full MSYS2. But the best solution for me was this answer by Michael Chen which installs pacman on git bash.