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How to complete the challenge POST /api/todos (415)

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Most APIs will report an error when the content-type is specified as a format that they do not support. Some APIs will parse the input using their default processing which can often result in a 500 error. The API Challenges checks the content-type and if it is unsupported returns a 415 status code, to see this we send a POST request to try and create a todo item but with unsupported content type.

POST /api/todos (415)

Issue a POST request on the /api/todos end point with an unsupported content type to generate a 415 status code

For this challenge we issue a request with a content-type which is unsupported.

  • POST request means we will send information in the body of the message
    • e.g. POST /api/todos sends to the todos endpoint
  • unsupported content type means that we will set content-type to something unknown eg. bob
  • add the X-CHALLENGER header to track progress
  • we know it has been rejected when we receive a 415 response
  • the body of the response should contain the full details of the error message

Basic Instructions

  • Issue a POST request to end point "/api/todos"
    • if running locally that endpoint would be
      • https://apichallenges.com/api/todos
  • The request should have an Content-Type header with an unsupported value e.g bob
  • add a valid payload, but it won't match the content type so doesn't matter, but adding a valid payload makes sure that the system is not ignoring the content type specified.
  • The request should have an X-CHALLENGER header to track challenge completion
  • The response status code should be 415 when all the details are valid.
  • Check the body of the response has JSON formatted error response
    • the system defaults to json for errors

Extras:

  • try setting the 'accept' header to specify the format of the error message in the response

Try it now

POST /api/todos with an unsupported Content-Type to trigger 415

Example Request

> POST /api/todos HTTP/1.1
> Host: apichallenges.com
> User-Agent: rest-client
> X-CHALLENGER: x-challenger-guid
> Content-Type: bob
> Accept: */*
> Content-Length: 106

|    {
|       "title": "create todo process payroll",
|       "doneStatus": true,
|       "description": ""
|     }

Example Response

< HTTP/1.1 415 Unsupported Media Type
< Connection: close
< Date: Sat, 17 Jul 2021 13:57:54 GMT
< Content-Type: application/json
< Access-Control-Allow-Origin: *
< Access-Control-Allow-Headers: *
< X-Challenger: 19b81e3e-841f-41a9-91c1-373f69091a56
< Server: Jetty(9.4.z-SNAPSHOT)
< Via: 1.1 vegur

Example Response body:

{
  "errorMessages": [
    "Unsupported Content Type - bob"
  ]
}

Overview Video

Watch on YouTube: "Solution to unsupported content type challenge"

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Lessons Learned

  • 415 Unsupported Media Type means the server does not accept the declared request-body format.
  • Content-Type is about what you send, not what you want back.
  • A correct body can still fail if its media type header tells the server to parse it incorrectly.

Suggested Experiments

  • Send a valid JSON body with Content-Type: application/xml and compare this error with a malformed JSON error.
  • Remove Content-Type completely and see whether the API guesses, rejects, or applies a default.
Experiment with this endpoint

 

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