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rsyslog_module

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Encodes technical requirements for rsyslog modules, including concurrency, metadata, and initialization.

QUICK START

How to use this skill

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Source SKILL.md: https://github.com/rsyslog/rsyslog/blob/HEAD/.agent/skills/rsyslog_module/SKILL.md

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rsyslog_module

This skill captures the essential technical patterns for authoring and maintaining rsyslog modules (plugins/contrib).

Quick Start

  1. Locking: Follow the "Belt and Suspenders" rule (assert() + if).
  2. State: pData (shared) vs WID (per-worker).
  3. Boilerplate: Use BEGINmodInit, CODESTARTmodInit, etc.

Detailed Instructions

1. Concurrency & Locking

Rsyslog v8 has a high-concurrency worker model.

  • Shared State (pData): Mutable state shared across workers MUST be protected by a mutex in pData.
  • Per-Worker State (WID): Never share wrkrInstanceData_t.
  • Belt and Suspenders: 
    assert(pData != NULL);
if (pData == NULL) {
    // Handle error gracefully
}
  • Headers: Every output module should have a "Concurrency & Locking" header block.

2. Module Lifecycle

Every module must implement and register standard entry points:

  • modInit(): Initialize static data and registry interfaces.
  • modExit(): Finalize and cleanup.
  • beginTransaction() / commitTransaction(): For efficient batch-based output.

3. Metadata Consistency

  • Location: MODULE_METADATA.yaml in the module directory.
  • Synchronization: Keep doc/ai/module_map.yaml in sync with locking and concurrency changes.

4. Build Configuration

  • Update plugins/Makefile.am and configure.ac when adding new modules.
  • Test Registration: Follow the "Define at Top, Distribute Unconditionally, Register Conditionally" pattern in tests/Makefile.am. See the rsyslog_test skill for details. This is critical for make distcheck validity.
  • Use MODULE_TYPE(eMOD_OUT) and other macros from runtime/module-template.h.

Related Skills

  • rsyslog_build: For compiling the module.
  • rsyslog_test: For creating module-specific smoke tests.
  • rsyslog_doc: For documentation requirements.