From 745023cfc2f1008051a08e19ce84469966b82aa4 Mon Sep 17 00:00:00 2001
From: Daniel Holmgren <dtholmgren@gmail.com>
Date: Fri, 19 May 2023 10:31:39 -0500
Subject: [PATCH] Improve .env (#20)

* describeFeedGenerator route + multiple feeds

* tweak readme

* improve env
---
 .env.example      | 12 +++++++++++-
 src/index.ts      | 14 ++++++++++----
 src/server.ts     | 11 ++---------
 src/well-known.ts | 10 +++++++---
 4 files changed, 30 insertions(+), 17 deletions(-)

diff --git a/.env.example b/.env.example
index ebd0e2b..4cfdab3 100644
--- a/.env.example
+++ b/.env.example
@@ -1,4 +1,14 @@
+# Whichever port you want to run this on 
 FEEDGEN_PORT=3000
+
+# Set to something like db.sqlite to store persistently
 FEEDGEN_SQLITE_LOCATION=":memory:"
+
+# Don't change unless you're working in a different environment than the primary Bluesky network
 FEEDGEN_SUBSCRIPTION_ENDPOINT="wss://bsky.social"
-FEEDGEN_SERVICE_DID="did:example:test"
+
+# Set this to the hostname that you intend to run the service at
+FEEDGEN_HOSTNAME="example.com"
+
+# Only use this if you want a service did different from did:web
+# FEEDGEN_SERVICE_DID="did:plc:abcde..."
\ No newline at end of file
diff --git a/src/index.ts b/src/index.ts
index a8486d7..4960044 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,11 +3,17 @@ import FeedGenerator from './server'
 
 const run = async () => {
   dotenv.config()
+  const hostname = maybeStr(process.env.FEEDGEN_HOSTNAME) ?? 'example.com'
+  const serviceDid =
+    maybeStr(process.env.FEEDGEN_SERVICE_DID) ?? `did:web:${hostname}`
   const server = FeedGenerator.create({
-    port: maybeInt(process.env.FEEDGEN_PORT),
-    sqliteLocation: maybeStr(process.env.FEEDGEN_SQLITE_LOCATION),
-    subscriptionEndpoint: maybeStr(process.env.FEEDGEN_SUBSCRIPTION_ENDPOINT),
-    serviceDid: maybeStr(process.env.FEEDGEN_SERVICE_DID),
+    port: maybeInt(process.env.FEEDGEN_PORT) ?? 3000,
+    sqliteLocation: maybeStr(process.env.FEEDGEN_SQLITE_LOCATION) ?? ':memory:',
+    subscriptionEndpoint:
+      maybeStr(process.env.FEEDGEN_SUBSCRIPTION_ENDPOINT) ??
+      'wss://bsky.social',
+    hostname,
+    serviceDid,
   })
   await server.start()
   console.log(
diff --git a/src/server.ts b/src/server.ts
index b57dffe..4e1449c 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -29,14 +29,7 @@ export class FeedGenerator {
     this.cfg = cfg
   }
 
-  static create(config?: Partial<Config>) {
-    const cfg: Config = {
-      port: config?.port ?? 3000,
-      hostname: config?.hostname ?? 'feed-generator.test',
-      sqliteLocation: config?.sqliteLocation ?? ':memory:',
-      subscriptionEndpoint: config?.subscriptionEndpoint ?? 'wss://bsky.social',
-      serviceDid: config?.serviceDid ?? 'did:example:test',
-    }
+  static create(cfg: Config) {
     const app = express()
     const db = createDb(cfg.sqliteLocation)
     const firehose = new FirehoseSubscription(db, cfg.subscriptionEndpoint)
@@ -63,7 +56,7 @@ export class FeedGenerator {
     feedGeneration(server, ctx)
     describeGenerator(server, ctx)
     app.use(server.xrpc.router)
-    app.use(wellKnown(cfg.hostname))
+    app.use(wellKnown(ctx))
 
     return new FeedGenerator(app, db, firehose, cfg)
   }
diff --git a/src/well-known.ts b/src/well-known.ts
index b869b6c..11c2304 100644
--- a/src/well-known.ts
+++ b/src/well-known.ts
@@ -1,17 +1,21 @@
 import express from 'express'
+import { AppContext } from './config'
 
-const makeRouter = (serverHostname: string) => {
+const makeRouter = (ctx: AppContext) => {
   const router = express.Router()
 
   router.get('/.well-known/did.json', (_req, res) => {
+    if (!ctx.cfg.serviceDid.endsWith(ctx.cfg.hostname)) {
+      return res.sendStatus(404)
+    }
     res.json({
       '@context': ['https://www.w3.org/ns/did/v1'],
-      id: `did:web:${serverHostname}`,
+      id: ctx.cfg.serviceDid,
       service: [
         {
           id: '#bsky_fg',
           type: 'BskyFeedGenerator',
-          serviceEndpoint: `https://${serverHostname}`,
+          serviceEndpoint: `https://${ctx.cfg.hostname}`,
         },
       ],
     })