Mesh
v0TransformsHoist
⚠️
This is the documentation for the old GraphQL Mesh version v0. We recommend upgrading to the latest GraphQL Mesh version v1.

Migrate to GraphQL Mesh v1

Hoist Field Transform

The hoist transform allows you to lift a field from one object type to a ‘parent’ root or object type. It is currently only available as a wrap transform.

npm i @graphql-mesh/transform-hoist-field
💡

Underneath it leverages the HoistField transform from the @graphql-tools/wrap package.

How to use?

Given the following schema:

type Query {
  users(limit: Int!, page: Int): UserSearchResult
}
 
type UserSearchResult {
  page: Int!
  results: [User!]!
}
 
type User {
  id: ID!
}

Simple hoisting

.meshrc.yaml
transforms:
  - hoist-field:
      - typeName: Query
        pathConfig:
          - users
          - results
        newFieldName: users

Will transform the given schema to:

type Query {
  users(limit: Int!, page: Int): [User!]!
}
 
type User {
  id: ID!
}

Filtering args via a default for the entire path

.meshrc.yaml
transforms:
  - hoist-field:
      - typeName: Query
        pathConfig:
          - users
          - results
        newFieldName: users
        filterArgsInPath: true # This flag sets the default for the entire path

Will transform the given schema to:

type Query {
  users: [User!]!
}
 
type User {
  id: ID!
}

Filtering args on specific levels of the path

.meshrc.yaml
transforms:
  - hoist-field:
      - typeName: Query
        pathConfig:
          - fieldName: users
            filterArgs:
              - limit
          - results
        newFieldName: users

Will transform the given schema to:

type Query {
  users(page: Int): [User!]!
}
 
type User {
  id: ID!
}

Config API Reference

  • typeName (type: String, required) - Type name that defines where field should be hoisted to
  • pathConfig - - Array of fieldsNames to reach the field to be hoisted (required) Array of:
    • String
    • object:
      • fieldName (type: String, required) - Field name
      • filterArgs (type: Array of String, required) - Match fields based on argument, needs to implement (arg: GraphQLArgument) => boolean;
  • newFieldName (type: String, required) - Name the hoisted field should have when hoisted to the type specified in typeName
  • alias (type: String)
  • filterArgsInPath (type: Boolean) - Defines if args in path are filtered (default = false)
PruneIntroduction