The GraphQL API

#Status and error codes

All GraphQL queries will always return an HTTP status code 200 unlike most APIs, where error handling is almost synonymous with HTTP codes. 401 - Unauthorized, 200 - OK. Handling errors in GraphQL is different with some challenges, and some ways to tackle them.

The status code 200 - OK doesn't always mean that the GraphQL server was able to process the query. Whenever an error occurs while processing a GraphQL query, its response to the client includes an errors array that contains each error that occurred.

The error will include these fields :

  • message: The message of the error
  • location: The location of the error in the query line and column
  • path: The path to the field that caused the error on the query
  • extensions: Additional details on the error. When the error comes from the PIM, this extensions field will also include two fields http_code and also http_message

Here are some examples of errors:

#Error regarding invalid query

Generally for these errors, the extensions field will be missing.

#Wrong query


    {
        referenceEntitiesRecords(referenceEntity: "designers")
    }
    

    {
      "errors": [
        {
          "message": "Field \"referenceEntitiesRecords\" of type \"ReferenceEntityRecordsCollection\" must have a selection of subfields. Did you mean \"referenceEntitiesRecords { ... }\"?",
          "locations": [
            {
              "line": 2,
              "column": 3
            }
          ]
        }
      ]
    }

#Wrong query parameter


    query MyQuery {
        # The search must be a valid JSON
        products(limit: 100, search: "parent!=null") {
            items {
                uuid
                parent {
                    code
                }
            }
        }
    }
    

    {
      "errors": [
        {
          "message": "the \"search\" parameter is not a valid JSON. Please see the documentation for help.",
          "locations": [
            {
              "line": 2,
              "column": 3
            }
          ],
          "path": [
            "products"
          ]
        }
      ],
      "data": {
        "products": null
      }
    }

#One-query limitation

You can find more detail on the Limitations - One-query


    {
        products {
            items {
                uuid
            }
        }
        categories {
            items {
                code
            }
        }
    }
    

    {
      "errors": [
        {
          "message": "Operation Error: Only one selection is allowed at once, found 2"
        }
      ]
    }

#Depth limitation

You can find more detail on the Limitations - Depth


    {
        products {
            items {
                uuid
                categories {
                    code
                }
                simpleAssociations {
                    type
                    products {
                        uuid
                        parent {
                            code
                            categories {
                                code
                            }
                        }
                    }
                }
            }
        }
    }
    

    {
      "errors": [
        {
          "message": "Depth Error: Query depth limit of 6 for query: [products] exceeded, found 7."
        }
      ]
    }

#Complexity limitation

You can find more detail on the Limitations - Query complexity


    {
        products(limit: 100) {
            items {
                uuid
                categories {
                    code
                }
                simpleAssociations {
                    type
                    products {
                        uuid
                        parent {
                            code
                        }
                    }
                }
            }
        }
    }
    

    {
      "errors": [
        {
          "message": "Cost Error: Query Cost limit of 5000 exceeded, found 6200. Reduce the limit argument or the requested fields"
        }
      ]
    }

#Error from the PIM

For these errors, the extensions field will always be present.

#Wrong data Extensions[http-code]: 422

This error occurs mainly when the data sent to the PIM are invalid. More detail is available on Api Rest - Response codes - 422


    query MyQuery {
      products(limit: 100, channel: "abc") {
        items {
          uuid
          parent {
            code
          }
          categories {
            code
            values
          }
        }
      }
    }
    

    {
      "errors": [
        {
          "message": "Scope \"abc\" does not exist.",
          "locations": [
            {
              "line": 2,
              "column": 3
            }
          ],
          "path": [
            "products"
          ],
          "extensions": {
            "http_code": 422,
            "http_message": "Request failed with status code 422"
          }
        }
      ],
      "data": {
        "products": null
      }
    }

#Invalid token Extensions[http-code]: 401

This error occurs mainly when authentication headers are invalid. More detail is available on Api Rest - Response codes - 401


    query MyQuery {
      products(limit: 100, channel: "abc") {
        items {
          uuid
      }
    }
    

    {
      "errors": [
        {
          "message": "The access token provided is invalid.",
          "locations": [
            {
              "line": 2,
              "column": 3
            }
          ],
          "path": [
            "products"
          ],
          "extensions": {
            "http_code": 401,
            "http_message": "Request failed with status code 401"
          }
        }
      ],
      "data": {
        "products": null
      }
    }

#Specific errors

In some cases we can get status code different from 200 - Ok

#415 Unsupported Media Type

This status indicates that the user has sent an empty HTTP POST request.

#429 Too Many Requests

This status indicates that the user has sent too many requests in a given amount of time ("rate limiting"). More details are available on Limitations - Rate limiting

#500 Internal Server Error

This status indicates that the server encountered an unexpected condition that prevented it from fulfilling the request. The status of the service can be found at https://status.akeneo.com/

Let's finish with more advanced notions

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