per-channel back off

[UnknownJoe796]

No description provided.

[UnknownJoe796]

Automated Review (commit d8b127b)Now I have a complete picture. Here's my review:

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PR #22: per-channel back off — Review Summary

Clean, well-structured addition of exponential backoff for websocket channel reconnection. The ChannelBackoff class is well-tested and the integration into BulkFetcher.WebsocketChannel is straightforward. Two issues found.

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1. Backoff bypassed when server rejects a channel (end without start)

File: ChannelBackoff.kt:29 / BulkFetcher.kt:164-177
Confidence: Medium

connectionOpenedAt is initialized to 0L and only updated when onConnectionOpened() is called (on receiving message.start). If the server rejects a channel by sending end=true without a prior start=true (confirmed possible from server-side MultiplexWebSocketHandler), then onConnectionOpened() is never called for that attempt.

When onConnectionClosed(false) runs:

connectionDuration = timeSource() - 0   // = current epoch ms, a huge number
huge_number < 5000                       // = false
→ backoff resets to 0

This means any built-up backoff is incorrectly wiped out by a rejection. In the specific scenario where a channel starts rapidly failing after some successful connections, a rejection resets the backoff counter and the client retries immediately.

Suggested fix: Track whether onConnectionOpened was called since the last close, and treat "never opened" as an immediate failure:

private var connectionOpenedAt: Long = 0L
private var wasOpened = false

fun onConnectionOpened() {
    connectionOpenedAt = timeSource()
    wasOpened = true
}

fun onConnectionClosed(wasIntentional: Boolean) {
    if (wasIntentional) {
        backoffMs = 0L
        wasOpened = false
        return
    }

    val isQuickFailure = if (!wasOpened) {
        true  // Never opened = immediate rejection = failure
    } else {
        (timeSource() - connectionOpenedAt) < stableConnectionThreshold.inWholeMilliseconds
    }
    wasOpened = false

    if (isQuickFailure) {
        backoffMs = if (backoffMs == 0L) initialBackoff.inWholeMilliseconds
                    else (backoffMs * 2).coerceAtMost(maxBackoff.inWholeMilliseconds)
    } else {
        backoffMs = 0L
    }
}

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2. package-lock.json accidentally committed

File: package-lock.json (5,154 new lines)
Confidence: High

A full package-lock.json was added in this PR. The project's .gitignore doesn't exclude it, but this is a Kotlin Multiplatform project where the sole package.json dependency (@js-joda/timezone) is a Gradle-managed JS interop dependency. This lockfile is almost certainly an accidental commit and adds noise to the diff. Consider adding package-lock.json to .gitignore and removing it from this PR.