gatsby: Gatsby Schema Customization API fails with gatsby-source-contentful and union types

Description

The new schema API always returns null on fields that reference multiple union types in Contentful when at least one of the types is not present.

I’m not sure if this is only affecting arrays of unions or single unions too.

in this instance the subSections field is not referencing any of the ContentfulSubSectionSibling union type

Steps to reproduce

clone: git clone https://github.com/sami616/gatsby-contentful-custom-schema-bug.git yarn install yarn start

Expected result

A list should render under the heading Section one

Actual result

My error message renders due to the subSections being null

Environment

System: OS: macOS 10.14 CPU: x64 Intel® Core™ i7-4770HQ CPU @ 2.20GHz Shell: 3.2.57 - /bin/bash Binaries: Node: 10.10.0 - ~/.nvm/versions/node/v10.10.0/bin/node Yarn: 1.13.0 - ~/.nvm/versions/node/v10.10.0/bin/yarn npm: 6.9.0 - ~/.nvm/versions/node/v10.10.0/bin/npm Browsers: Chrome: 73.0.3683.86 Firefox: 62.0.3 Safari: 12.0 npmPackages: gatsby: ^2.2.10 => 2.2.10 gatsby-plugin-react-helmet: ^3.0.0 => 3.0.0 gatsby-source-contentful: ^2.0.42 => 2.0.42 gatsby-transformer-remark: ^2.1.7 => 2.1.7 npmGlobalPackages: gatsby-cli: 2.4.3

About this issue

Original URL
State: closed
Created 5 years ago
Comments: 20 (10 by maintainers)

Most upvoted comments

With gatsby v2.5 the following should now work:

    type ContentfulSubSectionSibling implements Node {
      title: String
    }
    
    type ContentfulSubSection implements Node {
      title: String
    }
    
    union ContentfulSubSectionContentfulSubSectionSiblingUnion =
        ContentfulSubSection
      | ContentfulSubSectionSibling
    
    type ContentfulSection implements Node {
      title: String
      subSections: [ContentfulSubSectionContentfulSubSectionSiblingUnion]
        @link(from: "subSections___NODE")
    }
    
    type ContentfulPage implements Node {
      title: String
      slug: String
      sections: [ContentfulSection]
        @link(from: "sections___NODE")
    }

stefanprobst on May 17, 2019

Hey @stefanprobst I have something similar to what you wrote, but now gatsby says: Querying GraphQLUnion types is not supported. Did I miss something? Does it work if I write a custom resolver for it?

eddiecooro on Mar 6, 2020

I’m closing this as it should be fixed - feel free to open if there are still issues. Thanks

stefanprobst on May 23, 2019

Thanks @freiksenet - i just ran a small test and attached 2 out of 3 possible content types onto a field (instead of one like in my example) and it still failed - should gatsby at this point not know this should be a union?

ps - thank you for the example, attaching a manual resolver does seem to work

sami616 on Mar 29, 2019

cc @freiksenet @stefanprobst

#12272

wardpeet on Mar 25, 2019