[Technical Questions] Firebase (Firestore) Emulator Suddenly Failing

[Calvin-Xu]

In what area do you have a technical challenge?

Xcode, Simulator & Previews

Description

Firebase functionality in the app is suddenly not working for either me (it has been working for the past weeks) or Shamit (just set up and confirmed all working last week). Reverting to earlier commits did not solve this. The main error messages we get are:

11.3.0 - [FirebaseFirestore][I-FST000001] Could not reach Cloud Firestore backend. Connection failed 1 times. Most recent error: An internal error has occurred, print and inspect the error details for more information.
 This typically indicates that your device does not have a healthy Internet connection at the moment. The client will operate in offline mode until it is able to successfully connect to the backend.
11.3.0 - [FirebaseFirestore][I-FST000001] WatchStream (d0f3420b01) Stream error: 'Unknown: An internal error has occurred, print and inspect the error details for more information.'

> firebase emulators:start
i  emulators: Starting emulators: auth, firestore, storage
i  firestore: Firestore Emulator logging to firestore-debug.log
✔  firestore: Firestore Emulator UI websocket is running on 9150.

┌─────────────────────────────────────────────────────────────┐
│ ✔  All emulators ready! It is now safe to connect your app. │
│ i  View Emulator UI at http://127.0.0.1:4000/               │
└─────────────────────────────────────────────────────────────┘

┌────────────────┬────────────────┬─────────────────────────────────┐
│ Emulator       │ Host:Port      │ View in Emulator UI             │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Authentication │ 127.0.0.1:9099 │ http://127.0.0.1:4000/auth      │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Firestore      │ 127.0.0.1:8080 │ http://127.0.0.1:4000/firestore │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Storage        │ 127.0.0.1:9199 │ http://127.0.0.1:4000/storage   │
└────────────────┴────────────────┴─────────────────────────────────┘
  Emulator Hub running at 127.0.0.1:4400
  Other reserved ports: 4500, 9150

Issues? Report them at https://github.com/firebase/firebase-tools/issues and attach the *-debug.log files.

We use --useFirebaseEmulator. A representative firebase-debug.log entry (on my machine) is as below, showing Java error and stacktrace:

[debug] [2025-02-26T02:16:06.531Z] ----------------------------------------------------------------------
[debug] [2025-02-26T02:16:06.533Z] Command:       /opt/homebrew/Cellar/node/23.7.0/bin/node /opt/homebrew/bin/firebase emulators:start
[debug] [2025-02-26T02:16:06.534Z] CLI Version:   13.31.2
[debug] [2025-02-26T02:16:06.534Z] Platform:      darwin
[debug] [2025-02-26T02:16:06.534Z] Node Version:  v23.7.0
[debug] [2025-02-26T02:16:06.534Z] Time:          Tue Feb 25 2025 18:16:06 GMT-0800 (Pacific Standard Time)
[debug] [2025-02-26T02:16:06.534Z] ----------------------------------------------------------------------
[debug] 
[debug] [2025-02-26T02:16:06.623Z] > command requires scopes: ["email","openid","https://www.googleapis.com/auth/cloudplatformprojects.readonly","https://www.googleapis.com/auth/firebase","https://www.googleapis.com/auth/cloud-platform"]
[debug] [2025-02-26T02:16:06.624Z] > authorizing via signed-in user ([email protected])
[debug] [2025-02-26T02:16:06.754Z] openjdk version "23.0.2" 2025-01-21
OpenJDK Runtime Environment Homebrew (build 23.0.2)

[debug] [2025-02-26T02:16:06.754Z] OpenJDK 64-Bit Server VM Homebrew (build 23.0.2, mixed mode, sharing)

[debug] [2025-02-26T02:16:06.759Z] Parsed Java major version: 23
[info] i  emulators: Starting emulators: auth, firestore, storage {"metadata":{"emulator":{"name":"hub"},"message":"Starting emulators: auth, firestore, storage"}}
[debug] [2025-02-26T02:16:07.885Z] [logging] Logging Emulator only supports listening on one address (127.0.0.1). Not listening on ::1
[debug] [2025-02-26T02:16:07.885Z] [auth] Authentication Emulator only supports listening on one address (127.0.0.1). Not listening on ::1
[debug] [2025-02-26T02:16:07.885Z] [firestore] Firestore Emulator only supports listening on one address (127.0.0.1). Not listening on ::1
[debug] [2025-02-26T02:16:07.885Z] [firestore.websocket] websocket server for firestore only supports listening on one address (127.0.0.1). Not listening on ::1
[debug] [2025-02-26T02:16:07.885Z] [storage] Storage Emulator only supports listening on one address (127.0.0.1). Not listening on ::1
[debug] [2025-02-26T02:16:07.885Z] assigned listening specs for emulators {"user":{"hub":[{"address":"127.0.0.1","family":"IPv4","port":4400},{"address":"::1","family":"IPv6","port":4400}],"ui":[{"address":"127.0.0.1","family":"IPv4","port":4000},{"address":"::1","family":"IPv6","port":4000}],"logging":[{"address":"127.0.0.1","family":"IPv4","port":4500}],"auth":[{"address":"127.0.0.1","family":"IPv4","port":9099}],"firestore":[{"address":"127.0.0.1","family":"IPv4","port":8080}],"firestore.websocket":[{"address":"127.0.0.1","family":"IPv4","port":9150}],"storage":[{"address":"127.0.0.1","family":"IPv4","port":9199}]},"metadata":{"message":"assigned listening specs for emulators"}}
[debug] [2025-02-26T02:16:07.888Z] [hub] writing locator at /var/folders/jk/47ylq_6500v3wth9kvq_7hfm0000gn/T/hub-cs342-2025-feedbridge.json
[debug] [2025-02-26T02:16:07.891Z] Ignoring unsupported arg: auto_download {"metadata":{"emulator":{"name":"firestore"},"message":"Ignoring unsupported arg: auto_download"}}
[debug] [2025-02-26T02:16:07.891Z] Ignoring unsupported arg: single_project_mode_error {"metadata":{"emulator":{"name":"firestore"},"message":"Ignoring unsupported arg: single_project_mode_error"}}
[debug] [2025-02-26T02:16:07.891Z] Starting Firestore Emulator with command {"binary":"java","args":["-Dgoogle.cloud_firestore.debug_log_level=FINE","-Duser.language=en","-jar","/Users/calvinxu/.cache/firebase/emulators/cloud-firestore-emulator-v1.19.8.jar","--host","127.0.0.1","--port",8080,"--websocket_port",9150,"--project_id","cs342-2025-feedbridge","--rules","/Users/calvinxu/Projects/Coursework/CS342/2025-Feedbridge/firestore.rules","--single_project_mode",true],"optionalArgs":["port","webchannel_port","host","rules","websocket_port","functions_emulator","seed_from_export","project_id","single_project_mode"],"joinArgs":false,"shell":false,"port":8080} {"metadata":{"emulator":{"name":"firestore"},"message":"Starting Firestore Emulator with command {\"binary\":\"java\",\"args\":[\"-Dgoogle.cloud_firestore.debug_log_level=FINE\",\"-Duser.language=en\",\"-jar\",\"/Users/calvinxu/.cache/firebase/emulators/cloud-firestore-emulator-v1.19.8.jar\",\"--host\",\"127.0.0.1\",\"--port\",8080,\"--websocket_port\",9150,\"--project_id\",\"cs342-2025-feedbridge\",\"--rules\",\"/Users/calvinxu/Projects/Coursework/CS342/2025-Feedbridge/firestore.rules\",\"--single_project_mode\",true],\"optionalArgs\":[\"port\",\"webchannel_port\",\"host\",\"rules\",\"websocket_port\",\"functions_emulator\",\"seed_from_export\",\"project_id\",\"single_project_mode\"],\"joinArgs\":false,\"shell\":false,\"port\":8080}"}}
[info] i  firestore: Firestore Emulator logging to firestore-debug.log {"metadata":{"emulator":{"name":"firestore"},"message":"Firestore Emulator logging to \u001b[1mfirestore-debug.log\u001b[22m"}}
[debug] [2025-02-26T02:16:08.461Z] Feb 25, 2025 6:16:08 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketServer start
INFO: Started WebSocket server on ws://127.0.0.1:9150
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:16:08 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketServer start\nINFO: Started WebSocket server on ws://127.0.0.1:9150\n"}}
[debug] [2025-02-26T02:16:08.472Z] API endpoint: http:// {"metadata":{"emulator":{"name":"firestore"},"message":"API endpoint: http://"}}
[debug] [2025-02-26T02:16:08.472Z] 127.0.0.1:8080
If you are using a library that supports the FIRESTORE_EMULATOR_HOST environment variable, run:

   export FIRESTORE_EMULATOR_HOST=127.0.0.1:8080

If you are running a Firestore in Datastore Mode project, run:

   export DATASTORE_EMULATOR_HOST=127.0.0.1:8080

Note: Support for Datastore Mode is in preview. If you encounter any bugs please file at https://github.com/firebase/firebase-tools/issues.
Dev App Server is now running.

 {"metadata":{"emulator":{"name":"firestore"},"message":"127.0.0.1:8080\nIf you are using a library that supports the FIRESTORE_EMULATOR_HOST environment variable, run:\n\n   export FIRESTORE_EMULATOR_HOST=127.0.0.1:8080\n\nIf you are running a Firestore in Datastore Mode project, run:\n\n   export DATASTORE_EMULATOR_HOST=127.0.0.1:8080\n\nNote: Support for Datastore Mode is in preview. If you encounter any bugs please file at https://github.com/firebase/firebase-tools/issues.\nDev App Server is now running.\n\n"}}
[info] ✔  firestore: Firestore Emulator UI websocket is running on 9150. {"metadata":{"emulator":{"name":"firestore"},"message":"Firestore Emulator UI websocket is running on 9150."}}
[debug] [2025-02-26T02:16:10.580Z] Ignoring unsupported arg: port {"metadata":{"emulator":{"name":"storage"},"message":"Ignoring unsupported arg: port"}}
[debug] [2025-02-26T02:16:10.965Z] Temp file directory for storage emulator: /var/folders/jk/47ylq_6500v3wth9kvq_7hfm0000gn/T/firebase/storage/blobs {"metadata":{"emulator":{"name":"storage"},"message":"Temp file directory for storage emulator: /var/folders/jk/47ylq_6500v3wth9kvq_7hfm0000gn/T/firebase/storage/blobs"}}
[debug] [2025-02-26T02:16:10.972Z] Could not find VSCode notification endpoint: FetchError: request to http://localhost:40001/vscode/notify failed, reason: . If you are not running the Firebase Data Connect VSCode extension, this is expected and not an issue.
[info] 
┌─────────────────────────────────────────────────────────────┐
│ ✔  All emulators ready! It is now safe to connect your app. │
│ i  View Emulator UI at http://127.0.0.1:4000/               │
└─────────────────────────────────────────────────────────────┘

┌────────────────┬────────────────┬─────────────────────────────────┐
│ Emulator       │ Host:Port      │ View in Emulator UI             │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Authentication │ 127.0.0.1:9099 │ http://127.0.0.1:4000/auth      │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Firestore      │ 127.0.0.1:8080 │ http://127.0.0.1:4000/firestore │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Storage        │ 127.0.0.1:9199 │ http://127.0.0.1:4000/storage   │
└────────────────┴────────────────┴─────────────────────────────────┘
  Emulator Hub running at 127.0.0.1:4400
  Other reserved ports: 4500, 9150

Issues? Report them at https://github.com/firebase/firebase-tools/issues and attach the *-debug.log files.
 
[debug] [2025-02-26T02:23:20.006Z] Feb 25, 2025 6:23:20 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel
INFO: Connected to new websocket client
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:20 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel\nINFO: Connected to new websocket client\n"}}
[debug] [2025-02-26T02:23:21.727Z] Feb 25, 2025 6:23:21 PM io.gapi.emulators.netty.HttpVersionRoutingHandler channelRead
INFO: Detected non-HTTP/2 connection.
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:21 PM io.gapi.emulators.netty.HttpVersionRoutingHandler channelRead\nINFO: Detected non-HTTP/2 connection.\n"}}
[debug] [2025-02-26T02:23:21.788Z] Feb 25, 2025 6:23:21 PM io.gapi.emulators.netty.HttpVersionRoutingHandler channelRead
INFO: Detected HTTP/2 connection.
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:21 PM io.gapi.emulators.netty.HttpVersionRoutingHandler channelRead\nINFO: Detected HTTP/2 connection.\n"}}
[debug] [2025-02-26T02:23:23.041Z] Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed
INFO: Websocket client disconnected
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed\nINFO: Websocket client disconnected\n"}}
[debug] [2025-02-26T02:23:23.094Z] Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel
INFO: Connected to new websocket client
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel\nINFO: Connected to new websocket client\n"}}
[debug] [2025-02-26T02:23:23.521Z] Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed
INFO: Websocket client disconnected
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed\nINFO: Websocket client disconnected\n"}}
[debug] [2025-02-26T02:23:23.572Z] Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel
INFO: Connected to new websocket client
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:23 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler initChannel\nINFO: Connected to new websocket client\n"}}
[debug] [2025-02-26T02:23:24.696Z] Feb 25, 2025 6:23:24 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed
INFO: Websocket client disconnected
 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:24 PM com.google.cloud.datastore.emulator.firestore.websocket.WebSocketChannelHandler channelClosed\nINFO: Websocket client disconnected\n"}}
[debug] [2025-02-26T02:23:52.623Z] Feb 25, 2025 6:23:52 PM io.netty.channel.DefaultChannelPipeline onUnhandledInboundException
WARNING: An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.
java.net.SocketException: Connection reset
	at java.base/sun.nio.ch.SocketChannelImpl.throwConnectionReset(SocketChannelImpl.java:403)
	at java.base/sun.nio.ch.SocketChannelImpl.implRead(SocketChannelImpl.java:435)
	at java.base/sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:493)
	at io.netty.buffer.PooledByteBuf.setBytes(PooledByteBuf.java:255)
	at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1132)
	at io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:356)
	at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:151)
	at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:788)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650)
	at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562)
	at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:994)
	at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
	at java.base/java.lang.Thread.run(Thread.java:1575)

 {"metadata":{"emulator":{"name":"firestore"},"message":"Feb 25, 2025 6:23:52 PM io.netty.channel.DefaultChannelPipeline onUnhandledInboundException\nWARNING: An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.\njava.net.SocketException: Connection reset\n\tat java.base/sun.nio.ch.SocketChannelImpl.throwConnectionReset(SocketChannelImpl.java:403)\n\tat java.base/sun.nio.ch.SocketChannelImpl.implRead(SocketChannelImpl.java:435)\n\tat java.base/sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:493)\n\tat io.netty.buffer.PooledByteBuf.setBytes(PooledByteBuf.java:255)\n\tat io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1132)\n\tat io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:356)\n\tat io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:151)\n\tat io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:788)\n\tat io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724)\n\tat io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650)\n\tat io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562)\n\tat io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:994)\n\tat io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)\n\tat io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)\n\tat java.base/java.lang.Thread.run(Thread.java:1575)\n\n"}}

Reproduction

Run firebase emulators:start
Start the Feedbridge app and attempt operations that use Firestore.

Expected behavior

All operations work correctly as in our previous live demos.

Additional context

No response

Code of Conduct

• I agree to follow this course's Code of Conduct and Contributing Guidelines

[PSchmiedmayer]

Thank you for reach out out @Calvin-Xu; have you tried uninstalling it completely and re-installing it using homebrew?

[Calvin-Xu]

Thank you for the reply! Unfortunately I have tried that on firebase-cli and it has not solved the problem.

[PSchmiedmayer]

I would also suggest to reach out to the Firebase CLI team in their GitHub repo: https://github.com/firebase/firebase-tools/issues. They might be able to help if it indeed an issue in their simulator. It might also be that there is something else running on the ports that the emulator is using; have you tried to completely restart your Mac and just start the emulator without opening anything else? Have you installed or enabled any new features in the last weeks?