Mackerel's Log Feature Just Opened in Beta — Here's What It Takes to Wire It Into an OTLP Pipeline

TL;DR

Mackerel — Hatena's Japan-origin observability platform — opened its log feature as public beta on July 16, 2026. In response, this repository added Mackerel integration for shipping FSx for ONTAP file access audit logs, EMS events, and FPolicy events via the existing Lambda/OTel Collector pipeline.

The OTel Collector path worked immediately — just add an exporter config entry. But the direct-send path (Lambda → vendor OTLP endpoint, no Collector) exposed two compatibility gaps:

Mackerel requires a custom Mackerel-Api-Key header, not Bearer/Basic

Mackerel's OTLP endpoint only accepts Protobuf, rejecting OTLP/JSON outright