Feature: logging and exitcodes styfry sync (#124)

[archief2910]

Description

This PR addresses three issues reported in #124 related to the strfry sync command hanging indefinitely, oversized event content leaking into logs, and unhelpful error handling when connecting to relays that do not support negentropy.

Changes included:

Inactivity Timeout for strfry sync:

• Added --timeout=<seconds> CLI flag to cmd_sync.cpp. When set, the sync process aborts with exit code 1 if no WebSocket activity is observed for the specified duration.
• Implemented using hoytech::timer (the same pattern used by RelayCron and cmd_router) with a 1-second tick and std::atomic<uint64_t> lastActivity updated on every onConnect and onMessage event.
• Timeout fires via ws.trigger() → ws.onTrigger to ensure the exit runs on the WebSocket thread, consistent with the existing cmd_stream.cpp trigger pattern.
• Defaults to 0 (disabled) for full backward compatibility.

NOTICE Error Detection:

• Added a NOTICE message handler in cmd_sync.cpp. If a NOTICE is received before any NEG-MSG response (tracked by bool receivedNegMsg), and the notice text matches common error keywords (case-insensitive), the sync exits with code 1 and a clear log message indicating the relay likely does not support negentropy.
• This directly addresses the observed behavior where relays responding with "ERROR: negentropy disabled", "bad message type", "Command unrecognized", etc. caused the sync process to hang indefinitely.
• Non-error NOTICEs and NOTICEs received after a successful NEG-MSG exchange are logged as warnings and do not abort the sync.

Remove Event Content from Rejection Logs (WriterPipeline.h):

• Previously, rejected events were logged with up to 200 characters of their raw JSON content, creating a potential DoS vector where an attacker could send oversized events to fill relay disks with log data.
• Now only the event's hex ID and rejection reason are logged: Rejected event <id>: <reason>. Falls back to "unknown" if the ID cannot be parsed.
• This change affects all consumers of WriterPipeline (sync, import, router).

Truncate Large Messages in Error Paths:

• Unexpected messages and catch-all error log lines in cmd_sync.cpp now truncate the raw message string to 512 characters, preventing unbounded log growth from malformed or adversarial relay messages.

Related Issue

Closes #124

Motivation and Context

Users running strfry sync in automated pipelines against many relays encountered processes hanging indefinitely when relays did not support the negentropy protocol (NIP-77). These relays send a human-readable NOTICE instead of a NEG-ERR, leaving strfry sync waiting forever with no way to detect the failure. The --timeout flag and NOTICE detection together ensure the process always terminates with a meaningful exit code. Additionally, the rejection logging change eliminates a disk-fill vector that could be triggered by any client sending oversized events to a relay running sync or import.

How Has This Been Tested?

Functionally tested against live Nostr relays in WSL Ubuntu:

• --timeout flag verified present in --help output and confirmed it does not fire during an active sync against a responsive relay (relay.damus.io).
• NOTICE detection verified against nos.lol and nostr.mom (both respond with "ERROR: bad msg: negentropy disabled"): sync exits with code 1 within ~1 second instead of hanging.
• Rejection logging verified: large events rejected during a sync against relay.damus.io produce log lines of the form Rejected event <hex_id>: event too large: <size> with no event content.
• Full project builds cleanly with make.

Types of changes

• Non-functional change (docs, style, minor refactor)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly (CHANGES file).
• All new and existing tests passed.

[hoytech]

Thanks!