[agent] Fix a goroutine leak that happens when a websocket connection is closed. #143
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Fix a bug where the agent would leak goroutines when a websocket connection is closed. This was caused by the logic that coordinates reading and writing to the websocket connection to be too complicated, and using a channel for communicating when to exit instead of just cancelling the context. The use of that (unbuffered) channel then caused a leak when two separate goroutines both tried to send a message to the channel, but only one read was ever performed, and as a result the second goroutine would always hang indefinitely. This leak and the corresponding fix were confirmed using manual testing.
dli357
approved these changes
Nov 26, 2024
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Fix a bug where the agent would leak goroutines when a websocket connection is closed.
This was caused by the logic that coordinates reading and writing to the websocket connection to be too complicated, and using a channel for communicating when to exit instead of just cancelling the context.
The use of that (unbuffered) channel then caused a leak when two separate goroutines both tried to send a message to the channel, but only one read was ever performed, and as a result the second goroutine would always hang indefinitely.
This leak and the corresponding fix were confirmed using manual testing.
This change also fixes a bad coding pattern where we stored the context in a struct. Instead, we just store the methods from that context that are actually needed.