Add env var support, error handling, and race protection

src/index.ts

@@ -10,7 +10,9 @@ import {
 const PORT = Number(process.env.PORT) || 4040;
 
 // Initialize database
-initDb("collabd.db");
+const DB_PATH = process.env.COLLABD_DB || "collabd.db";
+initDb(DB_PATH);
+console.debug(`database initialized: ${DB_PATH}`);
 
 function isValidRoomName(name: unknown): name is string {
   if (typeof name !== "string") return false;

src/session.ts

@@ -1,7 +1,7 @@
 import type { ServerWebSocket } from "bun";
 import * as Y from "yjs";
+import { getUpdates, saveUpdate } from "./db";
 import { type AwarenessState, encode } from "./protocol";
-import { saveUpdate, getUpdates } from "./db";
 
 export interface WsData {
   room: string | null;
@@ -16,7 +16,7 @@ export class Session {
   doc: Y.Doc;
   clients: Set<Client> = new Set();
 
-  constructor(public name: string) {
+  constructor(public readonly name: string) {
     this.doc = new Y.Doc();
   }
 
@@ -50,8 +50,13 @@ export class Session {
   applyUpdate(update: Uint8Array, from: Client) {
     try {
       Y.applyUpdate(this.doc, update);
-      // Persist the update
+      // Persist the update (log but don't fail on db errors)
+      try {
         saveUpdate(this.name, update);
+      } catch (err) {
+        console.error(`failed to persist update in room ${this.name}:`, err);
+        // Continue - memory state is still updated
+      }
       // broadcast to others
       for (const client of this.clients) {
         if (client !== from) {
@@ -114,6 +119,13 @@ export function getOrCreateSession(name: string): Session {
     for (const update of updates) {
       Y.applyUpdate(session.doc, update);
     }
+
+    // Double-check pattern - another request may have created session while we loaded
+    const existing = sessions.get(name);
+    if (existing) {
+      return existing;
+    }
+
     sessions.set(name, session);
     console.debug(`session created: ${name}`);
   }