GraphQL query code generator for TypeScript types. This generates code specific to provided queries.

Example

You might have a model like this:

# model.graphql
type Query {
  getFoo(a: Int) {
    b
    c
  }
}

But want to write a query with a limited selection:

# query.graphql
query GetFoo {
  getFoo(a: 123) {
    b
  }
}

This library will generate limited types for you. It can be run either as a binary or as a library. For use as a binary, run:

$ graphql-query-codegen -q query.graphql model.graphql

You can also specify --loose to be less restrictive on checks, and -s ScalarName:tsTypeName to specify a scalar resolution. (e.g., -s AWSDateTime:string tells this code to render AWSDateTime as a string).

Library

You can also import this library. It exports a Builder class which is typed.

Notes

This treats the field __typename specially, and asssume it looks like String! but with a constant value of name of the type being requested (…unless that type specifically overrides it). (This is part of the spec, but is a bit weird.)

Known Issues

Input Validation

This library doesn't check that the input types of variables match the expected values in field arguments. For example, this is still allowed:

type Query {
  getFoo(a: Int!) {
    b
    c
  }
}

# This probably shouldn't pass: String is not Int.
# ...(although GraphQL treats both as "scalars" anyway)
query GetFoo($a: String!) {
  getFoo(a: $a) {
    b
  }
}

Fragments, Unions & Interfaces

This package has limited support for fragments, unions and interfaces.

It does not support top-level fragment definitions, but this should work fine:

# query.graphql

query GetWhatever {
  getInterface {
    __typename
    ... on OneOption {
      hasFieldA
    }
    ... on AnotherOption {
      hasFieldB
    }
  }
}