API Playground.

List all sample users.

[
  { "id": 1, "name": "Alice Johnson", "email": "alice@example.com", "role": "admin", "active": true, "age": 32 },
  { "id": 2, "name": "Bob Smith", "email": "bob@example.com", "role": "user", "active": false, "age": 28 }
]

Get a single user by id.

{ "id": 1, "name": "Alice Johnson", "email": "alice@example.com", "role": "admin", "active": true, "age": 32 }

Create a user. Not persisted — echoes back what a real create would return, so every visitor gets a clean demo.

{ "name": "Dana Lee", "email": "dana@example.com" }

{ "id": 47, "name": "Dana Lee", "email": "dana@example.com", "role": "user", "active": true, "age": null }

Update a user. Not persisted — merges your patch onto the seed record and echoes it back.

{ "active": false }

{ "id": 1, "name": "Alice Johnson", "email": "alice@example.com", "role": "admin", "active": false, "age": 32 }

Delete a user. Not persisted.

{ "deleted": true, "id": 1 }

List sample test cases. Supports an optional ?status= filter.

[
  { "id": 1, "title": "Login with valid credentials", "status": "active", "priority": "P1", "owner": "Alice Johnson" },
  { "id": 2, "title": "Login with locked account", "status": "draft", "priority": "P2", "owner": "Bob Smith" }
]

Update a test case. Status only moves forward: draft → active → archived. Requesting any other transition returns a 409 with the allowed next states — most practice APIs only demo happy-path CRUD; this one teaches conflict handling too.

{ "status": "active" }

{ "id": 2, "title": "Login with locked account", "status": "active", "priority": "P2", "owner": "Bob Smith" }

Allowed transitions: draft → active, active → archived. archived has no further transitions.

Requires an exact bearer token. Missing or wrong token → 401.

{ "message": "Authenticated.", "scope": "sample-api:read" }

Requires an x-api-key header. Deliberately distinguishes missing (401) from present-but-wrong (403) — a nuance most practice APIs collapse into one status code.

{ "message": "Authenticated.", "scope": "sample-api:read" }

Fails with a 500 roughly 30% of the time, at random — for practicing retry logic.

{ "message": "Success." }

Responds after an artificial delay — for practicing timeout handling. Delay is clamped to 8000ms server-side no matter what you request.

{ "message": "Responded after delay.", "delayMs": 3000 }

Allows 5 requests per 10 seconds per IP, then 429s with a Retry-After header — for practicing backoff logic.

{ "message": "OK", "remaining": 3, "limit": 5, "windowMs": 10000 }

Try the live demo below — it fires 6 requests back to back so you can watch the 429 happen.

A minimal GraphQL endpoint resolving "users" and "user(id: ...)" against the same seed data as the REST Users resource.

{ "query": "{ users { id name email } }" }

{ "data": { "users": [ { "id": 1, "name": "Alice Johnson", "email": "alice@example.com" } ] } }