Error: Invalid or incomplete introspection result. Ensure that you are passing "data" property of introspection response and no "errors" was returned alongside: undefined.

[Amnesthesia]

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---

Describe the bug

We output a URL from a previous step that we use as the input so that we can check a schema.gql file against one of our environments (dev, staging and prod). This usually fails, for whatever reason, often with a message like:

Error: Invalid or incomplete introspection result. Ensure that you are passing "data" property of introspection response and no "errors" was returned alongside: undefined., but I can access the site and fetch the introspection schema just fine (tested inside the github runner as well). Somehow, this comes out undefined.

This is what the step looks like:

Run kamilkisiela/graphql-inspector@master
  with:
    approve-label: breaking-schema-change
    fail-on-breaking: true
    name: ext.ourdomain.com
    schema: app/javascript/graphql/src/schema/schema_external.gql
    endpoint: https://ext.ourdomain.com/graphql
    rules: ignoreDescriptionChanges
  suppressRemovalOfDeprecatedField
  safeUnreachable
  
    github-token: ***
  env:
    GH_TOKEN: ***
    CURRENT_BRANCH_NAME: maintenance/external-schema
    TARGET_BRANCH_NAME: develop
    source_endpoint: app/javascript/graphql/src/schema/schema.gql
    source_endpoint_ext: app/javascript/graphql/src/schema/schema_external.gql
    target_environment: development
GraphQL Inspector started

Creating a check named "ext.ourdomain.com"
EXPERIMENTAL - Using Pull Request refs/pull/10248/merge
EXPERIMENTAL - Using develop as base schema ref

To Reproduce Steps to reproduce the behavior:

Set up multiple steps validating different schema files against different URLs output from a previous step.

Expected behavior

Schema to be fetched correctly every time.

Environment:

• Github Actions with ubuntu-latest (or our custom Github Actions Runners, it doesnt matter, its the same issue)
• kamilkisiela/graphql-inspector@master

[vwnd]

I am having the same issue, here.

[ianc-flwls]

@vwnd @Amnesthesia I also had this issue. I found the action expects your graphql server to assume you will always respond with JSON response.

I've fixed, see the above PR.

[sjustason]

I've had the same issue as well trying to use the Github Action, while the CLI works fine. So this works as expected:

graphql-inspector diff https://internal-dev-target.domain.com/graphql https://pr-sandbox.domain.com/graphql

But if I try the GHA using "schema" as the "new" schema from a pr sandbox, and the "old" or reference schema from our main dev environment, I get an error Invalid or incomplete introspection result:

    - name: GraphQL Schema Check
      uses: graphql-hive/graphql-inspector@master
      with:
        schema: 'https://pr-sandbox.domain.com/graphql'
        endpoint:  'https://internal-dev-target.domain.com/graphql'
        approve-label: 'approved-breaking-change'

I see the mentioned PR has a fix to supply the context-type for json for "endpoint", which seems likely my issue as well, but what if a URL is supplied for "schema" as well?