feat(bot): use Probot programmatic API with t3-env validation (#2015)

* feat(bot): add custom env var mapping for Fly.io deployment

- Create server.ts entry point that maps GITHUB_BOT_* env vars to Probot's expected names
- Update package.json start script to use new server entry point
- Update Dockerfile CMD to use new server entry point

This allows the bot to use custom environment variable names (GITHUB_BOT_APP_ID, GITHUB_BOT_PRIVATE_KEY, GITHUB_BOT_WEBHOOK_SECRET, etc.) while maintaining compatibility with Probot's default env var names.

Co-Authored-By: yujonglee <[email protected]>

* refactor(bot): use Probot programmatic API with t3-env validation

- Create env.ts with t3-env validation for GITHUB_BOT_* env vars
- Refactor server.ts to use Server class with Probot.defaults()
- Add @t3-oss/env-core and zod dependencies

This uses the programmatic API to pass appId, privateKey, and secret
directly to Probot instead of mapping environment variables.

Co-Authored-By: yujonglee <[email protected]>

---------

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: yujonglee

apps/bot/Dockerfile

@@ -22,4 +22,4 @@ FROM node:22-slim AS runtime
 WORKDIR /app
 ENV NODE_ENV="production"
 COPY --from=build /runtime ./
-CMD ["node", "node_modules/probot/bin/probot.js", "run", "./lib/index.js"]
+CMD ["node", "./lib/server.js"]

apps/bot/package.json

@@ -5,18 +5,20 @@
   "scripts": {
     "build": "tsc",
     "typecheck": "tsc --noEmit",
-    "start": "probot run ./lib/index.js",
+    "start": "node ./lib/server.js",
     "test": "vitest run"
   },
   "dependencies": {
-    "probot": "^13.4.5"
+    "@t3-oss/env-core": "^0.13.8",
+    "probot": "^13.4.5",
+    "zod": "^4.1.13"
   },
   "devDependencies": {
     "@types/node": "^20.0.0",
     "nock": "^14.0.5",
     "smee-client": "^2.0.0",
-    "vitest": "^2.0.0",
-    "typescript": "^5.8.3"
+    "typescript": "^5.8.3",
+    "vitest": "^2.0.0"
   },
   "overrides": {
     "@types/pg": "8.15.1"

apps/bot/src/env.ts

@@ -0,0 +1,14 @@
+import { createEnv } from "@t3-oss/env-core";
+import { z } from "zod";
+
+export const env = createEnv({
+  server: {
+    GITHUB_BOT_APP_ID: z.coerce.number().int().positive(),
+    GITHUB_BOT_PRIVATE_KEY: z.string().min(1),
+    GITHUB_BOT_WEBHOOK_SECRET: z.string().min(1),
+    GITHUB_BOT_CLIENT_ID: z.string().min(1).optional(),
+    GITHUB_BOT_CLIENT_SECRET: z.string().min(1).optional(),
+  },
+  runtimeEnv: process.env,
+  emptyStringAsUndefined: true,
+});

apps/bot/src/server.ts

@@ -0,0 +1,19 @@
+import { Probot, Server } from "probot";
+
+import { env } from "./env.js";
+import app from "./index.js";
+
+async function start() {
+  const server = new Server({
+    Probot: Probot.defaults({
+      appId: env.GITHUB_BOT_APP_ID,
+      privateKey: env.GITHUB_BOT_PRIVATE_KEY,
+      secret: env.GITHUB_BOT_WEBHOOK_SECRET,
+    }),
+  });
+
+  await server.load(app);
+  await server.start();
+}
+
+start();