Allow to configure the rootValue

[ggrossetie]

Story

As a user migrating from express-graphql, I want to pass a rootValue resolver. With express-graphql, I was able to do the following:

app.get('/graphql', graphqlHTTP((req, res) => ({
  schema,
  rootValue: resolvers
})))

Ideally, I would like to set rootValue as an option of createHandler

app.use(
  '/graphql',
  createHandler({ schema,  rootValue }),
)

Acceptance criteria

• user is able to configure a rootValue without overriding the whole ExecutionContext with onSubscribe
• user can find documentation on how to configure a rootValue

Note

Maybe using a rootValue is not recommended anymore? Maybe there's an alternative? For reference, here's how I declare my schema/resolvers:

module.exports = {
  /**
   * Create an article.
   */
  articles: async (args, { req }) => {
    // ...
  }
  /**
   * Delete an article.
   */
  deleteArticle: async (args, { req }) => {
    // ...
  },
}

const gql = require('graphql-tag')
const { buildASTSchema } = require('graphql')

module.exports = buildASTSchema(gql`
  type Article {
    _id: ID!
    title: String
    content: String
    createdAt: String
    updatedAt: String
  }

  type RootQuery {
    articles (user: ID): [Article!]!
  }

  type RootMutation {
    deleteArticle(article: ID!): Article!
  }

  schema {
    query: RootQuery
    mutation: RootMutation
  }
`)

[enisdenjo]

This makes sense! Thank you for opening an issue, I will tackle this rather soon.

[enisdenjo]

🎉 This issue has been resolved in version 1.10.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[manishbhatt94]

@enisdenjo There isn't much documentation available on how to use rootValue.

Like in the samples shared in the issue's description by this issue's author, we get access to query arguments and the request object as the 1st & 2nd parameters of each resolver defined via rootValue in express-graphql.

But in graphql-http, that isn't the case, I think, since graphql-http when calling the resolvers passed undefined as the 2nd argument instead of { req }.

[manishbhatt94]

Hey, I figured out how it works.. you need to use the context option in createHandler (which has access to the request) and then return whatever you want, and that would be passed as the 2nd argument when the library calls the resolvers. Sorry for posting the earlier comment, but the thing is the documentation is kinda not straightforward in the sense of its not mentioned anywhere with what arguments will resolvers defined under rootValue be called with.