`require-meta-sink`

Require a dedicated sink for the meta logger in configure() and configureSync() calls.

Severity	Fixable	Category
warn	no	`require-meta-sink`

Rationale

LogTape uses its own logging infrastructure to emit diagnostic messages about its internal operations (e.g., missing sinks, configuration errors). These messages are emitted under the ["logtape", "meta"] category.

Without a dedicated meta logger entry, LogTape's diagnostics may:

flow through a catch-all root logger, mixed with application logs,
be swallowed if a covering logger entry has no sinks, or
fall back to a built-in console sink (when no logger covers the meta category at all), accompanied by an informational diagnostic.

An explicit meta logger entry with at least one sink gives full control over where LogTape's own diagnostics go, independent of the rest of the logging configuration.

This rule warns whenever configure() or configureSync() is called without a logger entry whose category is ["logtape"] or ["logtape", "meta"] and whose sinks array is non-empty. The category must be written in array form: LogTape's own meta check inspects it as an array, so a bare string "logtape" does not configure the meta logger.

Examples

Incorrect

import { configure } from "@logtape/logtape";

await configure({
  sinks: { console: consoleSink },
  loggers: [
    // No meta logger entry → diagnostics fall back to the built-in console sink
    { category: ["my-app"], sinks: ["console"] },
  ],
});

Correct

import { configure } from "@logtape/logtape";

await configure({
  sinks: { console: consoleSink },
  loggers: [
    { category: ["my-app"], sinks: ["console"] },
    // Either array form is accepted:
    { category: ["logtape"], sinks: ["console"] },
    // or:
    { category: ["logtape", "meta"], sinks: ["console"] },
  ],
});

Configuration

ESLint v9 flat config:

import logtape from "@logtape/lint/eslint";

export default [
  {
    plugins: { "@logtape": logtape },
    rules: {
      "@logtape/require-meta-sink": "warn",
    },
  },
];

Deno Lint (deno.json):

{
  "unstable": ["lint"],
  "lint": {
    "plugins": ["jsr:@logtape/lint/deno"],
    "rules": {
      "include": ["logtape/require-meta-sink"]
    }
  }
}

require-meta-sink ​

Rationale ​

Examples ​

Incorrect ​