* fix nonce issues by locking populate and send transaction
Concurrent asynchronous population of transactions cause issues with nonces not being in sync with the transaction count for an account on chain. This was being mitigated by tracking a "last seen" nonce and locking inside of `populateTransaction` so that the nonce could be populated in a concurrent fashion. However, if there was an async cancellation before the transaction was sent, then the nonce would become out of sync. One solution was to decrease the nonce if a cancellation occurred. The other solution, in this commit, is simply to lock the populate and sendTransaction calls together, so that there will not be concurrent nonce discrepancies. This removes the need for "lastSeenNonce" and is overall more simple.
* remove lastSeenNonce
Internal nonce tracking is no longer needed since populate/sendTransaction is now locked. Even if cancelled midway, the nonce will get a refreshed value from the number of transactions from chain.
* chronos v4 exception tracking
* Add tests
* fix: modify unsubscribe cleanup routine
Ignore exceptions (other than CancelledError) if uninstallation of the filter fails. If it's the last step in the subscription cleanup, then filter changes for this filter will no longer be polled so if the filter continues to live on in geth for whatever reason, then it doesn't matter.
This includes a number of fixes:
- `CancelledError` is now caught inside of `getChanges`. This was causing conditions during `subscriptions.close`, where the `CancelledError` would get consumed by the `except CatchableError`, if there was an ongoing `poll` happening at the time of close.
- After creating a new filter inside of `getChanges`, the new filter is polled for changes before returning.
- `getChanges` also does not swallow `CatchableError` by returning an empty array, and instead re-raises the error if it is not `filter not found`.
- The tests were simplified by accessing the private fields of `PollingSubscriptions`. That way, there wasn't a race condition for the `newFilterId` counter inside of the mock.
- The `MockRpcHttpServer` was simplified by keeping track of the active filters only, and invalidation simply removes the filter. The tests then only needed to rely on the fact that the filter id changed in the mapping.
- Because of the above changes, we no longer needed to sleep inside of the tests, so the sleeps were removed, and the polling interval could be changed to 1ms, which not only makes the tests faster, but would further highlight any race conditions if present.
* docs: rpc custom port documentation
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Co-authored-by: Adam Uhlíř <adam@uhlir.dev>
Eric
Mark Spanbroek