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How to complete the challenge PATCH /api/todos/id (200) partial

By Updated

Use PATCH with Content-Type: application/json when you want to update selected fields on an existing todo. Partial JSON updates are an API-specific PATCH style.

PATCH /api/todos/id (200) partial

Issue a PATCH request to update an existing todo using a partial JSON payload.

  • Use PATCH /api/todos/{id} where {id} is an existing todo id.
  • Add Content-Type: application/json.
  • Send only the fields you want to change.
  • Do not include id in the payload.
  • The response should be 200.
  • Fields that are not in the payload should keep their existing values.
  • You can learn more about PATCH in the HTTP verbs tutorial.

Basic Instructions

  • Issue a PATCH request to:
    • https://apichallenges.com/api/todos/{{firstTodoId}}
  • The request should have an X-CHALLENGER header so the challenge is tracked.
  • The request body can be a partial JSON object:
{
  "title": "patched partial todo"
}

Try it now

If you don't know what todos are available then you can check by GET /api/todos. See the solution.

GET /api/todos to see what todos are available now

If you have already deleted all todos, create one using POST /api/todos. See the solution.

POST /api/todos to create a todo item for this challenge
PATCH /api/todos/{id} with partial JSON to update a todo

Example Request

> PATCH /api/todos/3 HTTP/1.1
> Host: apichallenges.com
> User-Agent: rest-client
> X-CHALLENGER: x-challenger-guid
> Content-Type: application/json
> Accept: application/json
>
> {"title":"patched partial todo"}

Example Response

< HTTP/1.1 200 OK
< Content-Type: application/json
< Accept-Patch: application/json, application/merge-patch+json, application/json-patch+json
< X-Challenger: x-challenger-guid

Returned body:

{
  "id": 3,
  "title": "patched partial todo",
  "doneStatus": false,
  "description": "existing description"
}

Lessons Learned

  • This API accepts PATCH with ordinary application/json as an API-specific partial update style.
  • Unlike PUT, a PATCH body can focus on the fields being changed.
  • Partial update tests should prove omitted fields remain unchanged.

Suggested Experiments

  • Change only doneStatus, then fetch the todo and confirm title and description were preserved.
  • Send an empty JSON object and observe whether the API treats it as no-op or invalid.
Experiment with this endpoint

 

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