circuitpython-usyslog

This CircuitPython module implements a simple syslog client for CircuitPython. Currently only UDP-based remote logging without timestamps is implemented. This is a fork of micropython-usyslog which has been updated to incorporate changes required for modern CircuitPython usage.

Features

• UDP Transport: Sends syslog messages over UDP via the CircuitPython-compatible socketpool module.
• Facility & Severity Constants: Predefined constants for all standard RFC 3164 facilities (KERN, USER, MAIL, DAEMON, …, LOCAL7) and severities (EMERG, ALERT, CRIT, ERR, WARN, NOTICE, INFO, DEBUG).
• RFC 3164-Style Header: Optional inclusion of a timestamp (Mmm dd hh:mm:ss), hostname, and application tag in each message.
• Configurable Defaults: Instantiation parameters allow setting default facility code, program tag, hostname, and whether timestamps are included.
• Runtime Overrides: Per-message overrides for tag, hostname, and timestamp inclusion in the log() call.
• Convenience Methods: Shortcut methods (alert(), critical(), error(), warning(), notice(), info(), debug()) for each severity level.
• Context Manager Support: The UDPClient implements __enter__/__exit__ for use with Python’s with statement, ensuring sockets are closed automatically.
• Resource Cleanup: Explicit close() method on UDPClient to free socket resources when done.

Background

An important part of creating IoT devices is the ability to gain observability through logging. One of the most widely-used methods of collecting logs from network devices is using syslog. This library can help when integrating logging capabilities in CircuitPython creations.

Dependencies

This module requires use of the socketpool library and the time module in CircuitPython for timestamp generation.

Requirements

In order to use this module, a remote syslog server is also necessary to accept remote messages.

API Reference

Facility Constants (RFC 3164)

• F_KERN, F_USER, F_MAIL, F_DAEMON, F_AUTH, F_SYSLOG, F_LPR, F_NEWS, F_UUCP, F_CRON, F_AUTHPRIV, F_FTP, F_NTP, F_AUDIT, F_ALERT, F_CLOCK, F_LOCAL0-F_LOCAL7

Severity Constants (RFC 3164)

• S_EMERG, S_ALERT, S_CRIT, S_ERR, S_WARN, S_NOTICE, S_INFO, S_DEBUG

Limitations

• No TCP transport or acknowledgment of receipt.
• Structured data (RFC 5424) is not supported.
• Timestamps are local and require a synchronized RTC or NTP on the device.

Reference Material

• RFC 3164: The BSD Syslog Protocol
• CircuitPython socketpool documentation
• CircuitPython time documentation

Disclaimer

This library is probably unstable and full of bugs. Like everything else on the internet, run/use at your own risk.