eslint-plugin-cache-keys

ESLint rules preventing the most common cache-layer bugs:

• cache-set-must-have-ttl — cache writes without a TTL field accumulate forever and OOM Redis.
• cache-key-must-be-prefixed — cache keys must start with a configured namespace prefix to prevent collisions when multiple apps share a Redis instance.
• cache-key-from-helper (opt-in) — cache keys must come from a configured helper function. Forces a single source of truth and makes invalidation tractable across a codebase.

The recommended config enables rules 1 and 2 at error. Rule 3 is opt-in because it requires you to declare your project's key-builder helpers.

Install

pnpm add -D @boring-stack-pkg/eslint-plugin-cache-keys

Peer deps: eslint >= 8.57, @typescript-eslint/parser >= 8, typescript >= 5.

Use (flat config)

import tsParser from "@typescript-eslint/parser";
import cacheKeys from "@boring-stack-pkg/eslint-plugin-cache-keys";

export default [
  {
    files: ["**/*.{ts,tsx}"],
    languageOptions: { parser: tsParser },
    plugins: { "cache-keys": cacheKeys },
    rules: {
      "cache-keys/cache-set-must-have-ttl": "error",
      "cache-keys/cache-key-must-be-prefixed": "error",
      "cache-keys/cache-key-from-helper": [
        "error",
        { helperNames: ["userCacheKey", "stripeEventCacheKey"] },
      ],
    },
  },
];

Or use the bundled config (rules 1–2 enabled, rule 3 off):

import cacheKeys from "@boring-stack-pkg/eslint-plugin-cache-keys";

export default [cacheKeys.configs.recommended];

Rules

| Rule | Description | Default in recommended | | ------------------------------------------------------------------------ | ---------------------------------------- | ---------------------- | | cache-set-must-have-ttl | .set calls must include ttlSeconds | error | | cache-key-must-be-prefixed | Keys must start with a configured prefix | error | | cache-key-from-helper | Keys must be built by configured helpers | off (opt-in) |

License

MIT.