Error: Cannot return null for non-nullable field when using multiple source handlers

[uknowpro]

Issue workflow progress

Progress of the issue based on the Contributor Workflow

• 1. The issue provides a reproduction available on Stackblitz

Make sure to fork this template and run yarn generate in the terminal.

Please make sure Mesh package versions under package.json matches yours.

• 2. A failing test has been provided
• 3. A local solution has been provided
• 4. A pull request is pending review

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Describe the bug
[CASE 1] Use merger: bare And multiple source handler(graphql, openapi) in mesh config

1. Use graphql from graphql handler
2. Then "Error: Cannot return null for non-nullable field" occurred.

• Using graphql from openapi handler is normal

[CASE 2] Un-use merger: bare And multiple source handler(graphql, openapi) in mesh config

1. Use graphql from graphql handler or openapi handler
2. Then "TypeError: Cannot read properties of undefined (reading 'Query')" occurred.

• The above two erros are occurred. (if namingConvention.mode is set to bare or wrap.)

To Reproduce
Steps to reproduce the behavior:

1. Go to: https://stackblitz.com/edit/node-hvpuk3
2. yarn
3. yarn start
4. In the GraphiQL Ui try the following query

query getUserInfo {
  getUserInfo(id: "1") {
    id
  }
}

Expected behavior
When using graphql and openapi handlers, I want the query to work by applying transforming normally without errors.

• (actual use) transforms
  • namingConvention
  • rename
  • filterSchema
  • resolversComposition

Environment:

• OS: MacOS
• @graphql-mesh/...:
  "@graphql-mesh/cli": "^0.80.1",
  "@graphql-mesh/config": "^8.0.34",
  "@graphql-mesh/graphql": "^0.32.2",
  "@graphql-mesh/merger-bare": "^0.15.49",
  "@graphql-mesh/openapi": "^0.33.38",
  "@graphql-mesh/runtime": "^0.44.35",
  "@graphql-mesh/transform-filter-schema": "^0.14.112",
  "@graphql-mesh/transform-naming-convention": "^0.12.2",
  "@graphql-mesh/transform-rename": "^0.13.1",
  "@graphql-mesh/transform-resolvers-composition": "^0.12.110"
• NodeJS: 16.13.0

Additional context
If downgrade only the @graphql-mesh/runtime to version 0.43.4 in the above package, all of the mentioned errors will not occur. All other conditions are the same.

[ardatan]

Bare merger and transforms cannot be used with GraphQL sources. You should always use wrap mode with GraphQL Sources.

[uknowpro]

if do not use bare merger, this response error occurs in both graphql source and openapi source.
"TypeError: Cannot read properties of undefined (reading 'Query')"

transform is applied to the openapi source, there is no error. (sure graphql source)

• (But) graphql-mesh/runtime@0.43.4
• no use bare merge
• wrap mode (namingConvention, rename, filterSchema, resolversComposition)