nelsonic
While running the Phoenix Chat Example App on localhost we are seeing this “noisy” warning:
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
code/phoenix-chat-example $ mix phx.server
[info] Running ChatWeb.Endpoint with Cowboy using http://0.0.0.0:4000
09:50:37 - info: compiled 6 files into 2 files, copied 3 in 1.7 sec
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
[info] JOIN "chat_room:lobby" to ChatWeb.ChatRoomChannel
Transport: Phoenix.Transports.WebSocket (2.0.0)
Serializer: Phoenix.Transports.V2.WebSocketSerializer
Parameters: %{}
[info] Replied chat_room:lobby :ok
[debug] QUERY OK source="messages" db=5.9ms decode=7.3ms
SELECT m0."id", m0."message", m0."name", m0."inserted_at", m0."updated_at" FROM "messages" AS m0 []
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
[warn] Ignoring unmatched topic "topic:subtopic" in ChatWeb.UserSocket
The warning just keeps being logged in the Terminal/Console indefinitely while the client is open …
Tried searching Google / GitHub / StackOverflow / Elixir Forum … 
but no obvious solution … 
https://forum.elixirforum.com/search?q=unmatched%20topic%20%22topic%3Asubtopic%22
If you know how to remove this warning, please share! Thanks! 
Additional Info
- OS: OSX 10.13.2 (latest)
- Elixir:
v1.5.3(latest) - Phoenix:
v1.3.0(current/stable) - Terminal: iTerm
v3.1.5
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kokolegorille
You did not clean up your assets/js/socket.js file…
Remove this (at the end of the file)
nelsonic
Thanks for your prompt and helpful reply @kokolegorille!
Commenting out those lines removed the warning.
Thanks!
Please mirror your answer to: https://stackoverflow.com/questions/48226553/phoenix-channels-warn-ignoring-unmatched-topic-topicsubtopic-how-to-avoid
to collect StackOverflow points.
kokolegorille
It’s ok, I am not using SO
nelsonic
Fair enough.
SO can be an “unwelcomming” forum.
This forum is way better anyway!
Thanks again! Hope you have a great day!