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Extend custom Types and Interfaces

See original GitHub issue

Summary

Hey Gatsby people,

I’m starting a project where my data source is a set of JSON files. In order to make them a bit more robust, I would like to get them extender using custom types. I already put something in place for custom types nested inside of a field of my JSON but the things are not working for me when I tried to do an interface for an array.

I was looking into the documentation for schema customization (https://www.gatsbyjs.org/docs/schema-customization/) but the portion for interfaces is not as detailed as I would like in order to complete the setup myself.

I’m thinking that I might be missing to create one resolver for the field that exposes the interface but not sure what is the best way to go for it.

My expectation is to get something like this as an output of the Graphql API:

{
    "__typename": "TriVideo",
    "kind": "TriVideo",
}

But what I’m getting right now is:

{
  "errors": [
    {
      "message": "Cannot read property 'type' of undefined",
      "locations": [
        {
          "line": 3,
          "column": 5
        }
      ],
      "path": [
        "pagesJson",
        "contentBlocks",
        0
      ],
      "stack": [
        "TypeError: Cannot read property 'type' of undefined",
        "    at typeComposer.setResolveType.node (/sandbox/node_modules/gatsby/dist/schema/schema.js:471:57)",
        "    at completeAbstractValue (/sandbox/node_modules/graphql/execution/execute.js:652:21)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:585:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:618:25",
        "    at Array.forEach (<anonymous>)",
        "    at forEach (/sandbox/node_modules/iterall/index.js:83:25)",
        "    at completeListValue (/sandbox/node_modules/graphql/execution/execute.js:614:24)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:573:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at resolveField (/sandbox/node_modules/graphql/execution/execute.js:435:10)",
        "    at executeFields (/sandbox/node_modules/graphql/execution/execute.js:275:18)",
        "    at collectAndExecuteSubfields (/sandbox/node_modules/graphql/execution/execute.js:713:10)",
        "    at completeObjectValue (/sandbox/node_modules/graphql/execution/execute.js:703:10)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:591:12)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:492:16"
      ]
    },
    {
      "message": "Cannot read property 'type' of undefined",
      "locations": [
        {
          "line": 3,
          "column": 5
        }
      ],
      "path": [
        "pagesJson",
        "contentBlocks",
        1
      ],
      "stack": [
        "TypeError: Cannot read property 'type' of undefined",
        "    at typeComposer.setResolveType.node (/sandbox/node_modules/gatsby/dist/schema/schema.js:471:57)",
        "    at completeAbstractValue (/sandbox/node_modules/graphql/execution/execute.js:652:21)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:585:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:618:25",
        "    at Array.forEach (<anonymous>)",
        "    at forEach (/sandbox/node_modules/iterall/index.js:83:25)",
        "    at completeListValue (/sandbox/node_modules/graphql/execution/execute.js:614:24)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:573:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at resolveField (/sandbox/node_modules/graphql/execution/execute.js:435:10)",
        "    at executeFields (/sandbox/node_modules/graphql/execution/execute.js:275:18)",
        "    at collectAndExecuteSubfields (/sandbox/node_modules/graphql/execution/execute.js:713:10)",
        "    at completeObjectValue (/sandbox/node_modules/graphql/execution/execute.js:703:10)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:591:12)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:492:16"
      ]
    },
    {
      "message": "Cannot read property 'type' of undefined",
      "locations": [
        {
          "line": 3,
          "column": 5
        }
      ],
      "path": [
        "pagesJson",
        "contentBlocks",
        2
      ],
      "stack": [
        "TypeError: Cannot read property 'type' of undefined",
        "    at typeComposer.setResolveType.node (/sandbox/node_modules/gatsby/dist/schema/schema.js:471:57)",
        "    at completeAbstractValue (/sandbox/node_modules/graphql/execution/execute.js:652:21)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:585:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:618:25",
        "    at Array.forEach (<anonymous>)",
        "    at forEach (/sandbox/node_modules/iterall/index.js:83:25)",
        "    at completeListValue (/sandbox/node_modules/graphql/execution/execute.js:614:24)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:573:12)",
        "    at completeValueCatchingError (/sandbox/node_modules/graphql/execution/execute.js:495:19)",
        "    at resolveField (/sandbox/node_modules/graphql/execution/execute.js:435:10)",
        "    at executeFields (/sandbox/node_modules/graphql/execution/execute.js:275:18)",
        "    at collectAndExecuteSubfields (/sandbox/node_modules/graphql/execution/execute.js:713:10)",
        "    at completeObjectValue (/sandbox/node_modules/graphql/execution/execute.js:703:10)",
        "    at completeValue (/sandbox/node_modules/graphql/execution/execute.js:591:12)",
        "    at /sandbox/node_modules/graphql/execution/execute.js:492:16"
      ]
    }
  ],
  "data": {
    "pagesJson": {
      "contentBlocks": [
        null,
        null,
        null
      ]
    }
  }
}

Environment

I’ve created a minimal setup of my local within CodeSandbox https://codesandbox.io/s/quirky-pare-bk01t

Issue Analytics

State:
Created 4 years ago
Comments:8 (6 by maintainers)

Top GitHub Comments

1reaction

marcysuttoncommented, Jan 29, 2020

@Jhony0311 we have Using Schema Customization coming up as a workflow to evaluate next quarter. If there are things you feel could be improved in the docs in the meantime, we would welcome a PR! Another way to contribute would be to get a jump start on the workflow evaluation as outlined here (# 15): https://github.com/gatsbyjs/gatsby/issues/13708

0reactions

github-actions[bot]commented, Feb 29, 2020

Hey again!

It’s been 30 days since anything happened on this issue, so our friendly neighborhood robot (that’s me!) is going to close it. Please keep in mind that I’m only a robot, so if I’ve closed this issue in error, I’m HUMAN_EMOTION_SORRY. Please feel free to reopen this issue or create a new one if you need anything else. As a friendly reminder: the best way to see this issue, or any other, fixed is to open a Pull Request. Check out gatsby.dev/contribute for more information about opening PRs, triaging issues, and contributing!

Thanks again for being part of the Gatsby community! 💪💜

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