Merge pull request #110 from local-first-web/handle-connection-errors

Add error handling to the Connection state machine

packages/auth/src/connection/Connection.ts

@@ -24,6 +24,7 @@ import {
   TIMEOUT,
   createErrorMessage,
   type ConnectionErrorType,
+  UNHANDLED,
 } from 'connection/errors.js'
 import { getDeviceUserFromGraph } from 'connection/getDeviceUserFromGraph.js'
 import * as identity from 'connection/identity.js'
@@ -694,10 +695,16 @@ export class Connection extends EventEmitter<ConnectionEvents> {
     this.#machine = createActor(machine)
 
     // emit and log all transitions
-    this.#machine.subscribe(state => {
-      const summary = stateSummary(state.value as string)
-      this.emit('change', summary)
-      this.#log(`⏩ ${summary} `)
+    this.#machine.subscribe({
+      next: state => {
+        const summary = stateSummary(state.value as string)
+        this.emit('change', summary)
+        this.#log(`⏩ ${summary} `)
+      },
+      error: error => {
+        console.error('Connection encountered an unhandled error', error)
+        this.#fail(UNHANDLED)
+      },
     })
 
     // add automatic logging to all events

packages/auth/src/connection/errors.ts

@@ -8,6 +8,7 @@ export const MEMBER_REMOVED = 'MEMBER_REMOVED' as const
 export const NEITHER_IS_MEMBER = 'NEITHER_IS_MEMBER' as const
 export const SERVER_REMOVED = 'SERVER_REMOVED' as const
 export const TIMEOUT = 'TIMEOUT' as const
+export const UNHANDLED = 'UNHANDLED' as const
 
 export const connectionErrors: Record<string, ErrorDefinition> = {
   [DEVICE_REMOVED]: {
@@ -48,6 +49,9 @@ export const connectionErrors: Record<string, ErrorDefinition> = {
     localMessage: "We didn't hear back from the peer; giving up",
     remoteMessage: "The peer didn't hear back from you, so they gave up",
   },
+  [UNHANDLED]: {
+    localMessage: 'An unhandled error occurred',
+  },
 }
 
 /** Creates an error payload with an appropriate message for the local or remote user */