investigate listen routine shutdown

[switchupcb]

Problem

Session listen routine shutdown at a random point, which causes the bot to go offline.

This issue is related, but not a followup to #79.

Information

Here is a log showing an error from the listen routine.

This error occurs 11 hours after the bot was started and after 2 successful reconnects. The listen routine shutdown ~4 hours after reconnecting.

{"level":"info","time":"2025-02-25T07:39:51.243316838Z","session":"0bf54ed815cb64492b3b442af76aecee","message":"reconnecting session due to Opcode 7 Reconnect"}
{"level":"info","time":"2025-02-25T07:39:52.571111584Z","session":"19a66158dd23faa53df0a0cce17ea441","message":"received Ready event"}

{"level":"info","time":"2025-02-25T11:15:50.047799401Z","session":"19a66158dd23faa53df0a0cce17ea441","message":"closed listen routine"}
{"level":"info","time":"2025-02-25T11:15:50.047882793Z","session":"19a66158dd23faa53df0a0cce17ea441","client":"948649712649662524","message":"received signal: <-s.Context.Done with state \"connected\""}
{"level":"info","time":"2025-02-25T11:15:50.063901311Z","session":"19a66158dd23faa53df0a0cce17ea441","message":"closed pulse routine"}
{"level":"info","time":"2025-02-25T11:15:50.064162719Z","session":"19a66158dd23faa53df0a0cce17ea441","message":"closed heartbeat routine"}
{"level":"info","time":"2025-02-25T11:15:50.064255893Z","session":"19a66158dd23faa53df0a0cce17ea441","client":"948649712649662524","error":"listen: failed to get reader: failed to read frame header: EOF","message":"<-s.Context.Done manager wait error result"}

[switchupcb]

Solution

This issue is solved with a disgo.Session disconnect event tool which lets the user control what happens when a Session unexpectedly disconnects.

Information

I ran a modified disgo.go bot for 2 days without downtime at the program-level, but with short downtime (i.e. seconds) between reconnection when the Session experiences the EOF issue.

{"level":"info","time":"2025-02-26T03:45:30.748098179Z","session":"","client":"948649712649662524","message":"connecting session"}
{"level":"info","time":"2025-02-27T11:26:57.894743578Z","session":"2785b2978485191761952439d6c8f304","message":"received unknown Gateway Close Event Code 1001 with reason \"CloudFlare WebSocket proxy restarting\""}

The program shutdown when the "unknown" Gateway Close Event Code 1001 occurred.

This bot experienced the EOF error 7 times during this time, but connected back each time.

Here is the reason this issue occurs

1. incorrect s.Conn manipulation (which would be uncovered in the answer to failed to get reader: failed to read frame header: EOF coder/websocket#520)
2. Discord closing connection unexpectedly without warning.

Implementation

Add a disgo.Session disconnect event tool which lets the user control what happens when a Session disconnects.

The client can disconnect unexpectedly at any time due to a number of reasons (e.g., client internet issues, discord connection, etc). So, we must give more control to the user to determine how the bot reacts to this disconnection.

Here is how this feature must be implemented.

1. The user uses Session.Wait() to wait for a Session to disconnect, which is already implemented.
2. A disgo tool is used reconnect the session when a parameter ...func(error) bool returns true or stop after a set number of reconnections.
   i. The user is able to use a default list of predefined func(error) bool which is updated when unexpected disconnections which warrant a reconnect occur.

The user can then use tools.InterceptSignal on a main thread and the implemented tools.ReconnectUnpexpectedDisconnection on a goroutine to be able to terminate a program while also reconnecting a session whenever it unexpectedly disconnects.