Creating entity with incorrect related entity ID, still gets created.

[Jinjeleta]

Creating new entity with related entity's ID, which does not exist, still gets created, however response comes with an error message. An example:

POST /answers 

{
  "data":{
    "type": "answers",
    "attributes": {
    	"body": "My new answer to your question!"
    },
    "relationships": {
    	"question": { "data": { "type": "questions", "id": 999}}
    }
  }
}

Response:
{
  "errors": [{
    "status": "404",
    "title": "Not Found",
    "detail": "Could not find Question with id 999."
  }],
    "jsonapi": {
      "version": "1.0"
    }
}

However doing another request to get all answers, still returns freshly created entity, however I think it should have rolled back.

GET /answers

{
    "data": [
        {
            "id": "1",
            "type": "answers",
            "attributes": {
                "body": "My new answer to your question!",
                "created-at": "2016-12-01T19:38:28.008Z",
                "updated-at": "2016-12-01T19:38:28.008Z"
            },
            "relationships": {
                "question": {
                    "data": null
                }
            },
            "links": {
                "self": "http://localhost:4000/answers/1"
            }
        }
    ],
    "links": {
        "self": "http://localhost:4000/answers",
        "first": "http://localhost:4000/answers",
        "last": "http://localhost:4000/answers",
        "prev": null,
        "next": null
    },
    "jsonapi": {
        "version": "1.0"
    }
}

We can see that from log as well:

------------------------------------------------------------------------------------------------------

[2016-12-01T19:38:28.094Z] INSERT INTO "answers" ("body", "created_at", "question_id", "updated_at") VALUES ('MY NEW ANSWER TO YOUR QUESTION!', '2016-12-01 20:38:28.008', NULL, '2016-12-01 20:38:28.008')

------------------------------------------------------------------------------------------------------

[2016-12-01T19:38:28.137Z] SELECT "questions"."id" AS "id", "questions"."title" AS "title", "questions"."body" AS "body", "questions"."created_at" AS "createdAt", "questions"."updated_at" AS "updatedAt" FROM "questions" WHERE "questions"."id" = 999 LIMIT 1

------------------------------------------------------------------------------------------------------

[2016-12-01T19:38:28.142Z] Error: Could not find Question with id 999.
    at /home/student/Projects/lux/examples/forum/node_modules/lux-framework/src/packages/database/query/runner/index.js:85:25
    at Generator.next (<anonymous>)
    at step (/home/student/Projects/lux/examples/forum/dist/bundle.js:228:30)
    at /home/student/Projects/lux/examples/forum/dist/bundle.js:239:13

------------------------------------------------------------------------------------------------------

[2016-12-01T19:38:28.162Z] Processed POST "/answers" from ::ffff:127.0.0.1 with 404 Not Found by AnswersController#create

[Jinjeleta]

Probably this will get fixed with https://github.com/postlight/lux/pull/527 as well.

[zacharygolba]

Is the intent here to create the answer and the question in the same request or to create an answer for a question that already exists?

I can confirm that we have a bug with updating the belongs-to side of relationships in the current stable version 1.0.X. That will be fixed in #527.

[Jinjeleta]

Actually, intention was to test whether this will be handled properly, when creating an answer to non-existing question. This scenario could happen in real cases as well, when client is slightly out of sync and tries to create answer to recently deleted question.

[zacharygolba]

Hmm that's a good point.

What would you expect to happen here? A 404 due to the related record not existing? Is that better than just ignoring the invalid resource?

I can't seem to find anything about this in the JSON API spec.

[Jinjeleta]

In my opinion response is correct and fine.

We are just missing to ensure that behind the scenes entity will not get created with null or incorrect ID of related entity, when it gives a such response back.