Module augmentation of Context.octokit.git

[ghost]

I'd like to add a new method to the Context.octokit.git class in a Probot + TypeScript project. This is my first time using TypeScript (though I know OOP from other languages) and I found out that extending a prototype is called Module augmentation in TS.
This is what I'm trying to achieve (doesn't work, pseudo-code):

import { Context } from 'probot';

declare module 'probot' {
    interface Context {
        octokit: {
            git: {
                createBranch(name: String): boolean;
            };
        };
    }
}

Context.prototype.octokit.git.createBranch = async (name: String) {
    // I need the context instance available here
}

Can somebody help me out? ^^

[gr2m]

You can extend Octokit using plugins

import { ProbotOctokit } from 'probot'

export async function createBranch(octokit: ProbotOctokit)  {
  return {
    async createBranch(string) {
      // your code here, use the `octokit` instance
      return true
    }
  }
}

Then you can pass your own Octokit constructor, depending on how you are running your app. If you use a long living process, you can use the Server export

import { Server, Probot, ProbotOctokit } from "probot";
import { createBranch } from "./create-branch-plugin.js";
import { app } from "./index.js"

async function startServer() {
  const server = new Server({
    Probot: createProbot({
      Octokit: ProbotOctokit.plugin(createBranch)
    }),
  });

  await server.load(app);

  server.start();
}

Then you can use octokit.createBranch(name) in your app. It will have the right typing.

The environment variables for configuration should still work, they are read out by createProbot, with the exception of the server-related environment variables HOST, POST, and WEBHOOK_PATH. You will have to set the respective new Server({ host, post, webhookPath }) options instead

The octokit.git.* are generated from GitHub's OpenAPI spec. I would not do any changes on the .git. or any of the other namespaces created by @octokit/plugin-rest-endpoint-methods plugin, as we don't know what methods will be added in future and they might conflict with the ones you add.