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Sarj Standards

TypeScript · correctness

prefer-schema-for-api-payload

eslint:prefer-schema-for-api-payload

Require Zod (or similar) schema validation on `response.json()` / `JSON.parse()` results before property access.

Default
error
Fix
none
Languages
typescript

Why

External JSON is untrusted at runtime even when its expected TypeScript shape is known statically.

Fix

Parse the payload through a schema or establish a recognized runtime validation guard before reading fields.

Before / after

Executed by this rule’s unit tests.

Before

Do not trust response JSON directly

src/client.ts · focus
async function load(response) { const body = await response.json(); return body.id; }

After

Validate before property access

src/client.ts · focus
async function load(response) { const body = UserSchema.parse(await response.json()); return body.id; }

Limits

  • Test fixtures, generated clients, local JSON files, and recognized validation guards are excluded.

Message IDs

unparsedJsonAccess