Separate DB worker from sync

[mkysel]

The DB goroutine lifecycle was tied to the lifecycle of the GRPC connection. There were no guarantees that the DB conn won't outlive the main routine when being rebuilt. This could lead to concurrent DB writing coroutines, out-of-order writes and other nastiness.

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[mkysel]

guarantees that the reader routine can exit if the main routine is doing something else. Otherwise the write to err might block forever.

[macroscopeapp]

Separate database worker from sync by extracting envelope storage logic from originatorStream into new EnvelopeSink component

The envelope storage logic is extracted from the originatorStream struct into a new EnvelopeSink component that handles database operations through a queue-based worker pattern. The changes include:

• Creates new envelopeSink.go with EnvelopeSink struct containing methods for storing envelopes, handling reserved topics, calculating fees, and getting payer IDs
• Refactors originatorStream.go to remove database-related fields and methods, adding writeQueue field to pass envelopes to EnvelopeSink
• Updates syncWorker.go to create write queue channels and coordinate between originatorStream and EnvelopeSink components
• Modifies originatorStream_test.go with new test functions for EnvelopeSink and updated existing tests to work with separated components

📍Where to Start

Start with the subscribeToNode method in syncWorker.go to see how the write queue is created and how the EnvelopeSink and originatorStream components are coordinated.

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Macroscope summarized 9804f6b.

[mkysel]

other than the struct, all content is copied from the original place without changes.

[fbac]

LGTM. Love the separation of concerns.