How to complete the challenge `GET /api/todos (200) ? filter and _sortBy`

By Alan RichardsonPublished 2026-07-30

How to issue a GET request on a top level entity endpoint, filter the returned todos, and sort the filtered results.

GET /api/todos (200) ? filter and _sortBy

Issue a GET request on the /api/todos end point with a query filter and a query parameter to sort the filtered todos, requesting the response in JSON format.

todo fields can be used as URL parameters to filter collection results
_sortBy is the URL parameter used to sort collection results
prefix a sort field with - to sort descending
for example, doneStatus=false&_sortBy=-id returns only not done todos, sorted by id from highest to lowest
ensure header Accept: application/json exists so the filtered and sorted todo collection is visible as JSON

Basic Instructions

Issue a GET request to end point "/api/todos"
- https://apichallenges.com/api/todos
The request should have an X-CHALLENGER header to track challenge completion
The request should have an Accept: application/json header so the API returns todos in JSON format
Add doneStatus=false and _sortBy=-id as URL parameters:
- https://apichallenges.com/api/todos?doneStatus=false&_sortBy=-id
The response status code should be 200 because the request is accepted
Check that all returned todos have doneStatus set to false, and that the ids are descending

Try it now

GET /api/todos?doneStatus=false&_sortBy=-id to filter and sort todos

Example Request

> GET /api/todos?doneStatus=false&_sortBy=-id HTTP/1.1
> Host: apichallenges.com
> User-Agent: rest-client
> X-CHALLENGER: x-challenger-guid
> Accept: application/json

Example Response

< HTTP/1.1 200 OK
< Connection: close
< Content-Type: application/json
< X-Challenger: x-challenger-guid

Returned body:

{
  "todos": [
    {
      "id": 10,
      "title": "not done with highest id",
      "doneStatus": false,
      "description": ""
    },
    {
      "id": 3,
      "title": "not done with lower id",
      "doneStatus": false,
      "description": ""
    }
  ]
}

Lessons Learned

Combining a filter with _sortBy tests operation order: narrow the set, then order the survivors.
Multi-parameter queries need assertions for both inclusion and ordering.
Sorting a filtered subset can hide missed data if you only inspect the first item.

Suggested Experiments

Sort the filtered results by -title and verify every returned todo still matches doneStatus.
Add one done and one not-done fixture with similar titles to prove sorting does not override filtering.

Experiment with this endpoint

How to complete the challenge GET /api/todos (200) ? filter and _sortBy