gql-merge

Tools for merging GraphQL documents

Table of Contents

• Background
• Installation
• CLI
• API

Background

This repo contains tools for merging definitions into multiple GraphQL documents into one. For example, say you have these two files GraphQL files:

type Post {
  id: ID!
  content: String
}

type Query {
  postById(id: ID!): Post
}

type Author {
  id: ID!
  name: String
}

type Query {
  postsByAuthorId(id: ID!): [Post]
}

You can use the gql-merge CLI to combine these files into one:

$ gql-merge --out-file schema.graphql testdata/readme*

The resulting file would look like this:

type Post {
  id: ID!
  content: String
}

type Query {
  postById(id: ID!): Post
  postsByAuthorId(id: ID!): [Post]
}

type Author {
  id: ID!
  name: String
}

Installation

$ npm i -g gql-merge

CLI

$ gql-merge -h

  Usage: gql-merge [options] <glob ...>

  Tools for merging GraphQL documents

  Options:

    -h, --help             output usage information
    -V, --version          output the version number
    -o, --out-file <path>  Output GraphQL file, otherwise use stdout
    -v, --verbose          Enable verbose logging

  Examples:

    $ gql-merge **/*.graphql > schema.graphql
    $ gql-merge -o schema.graphql **/*.graphql
    $ gql-merge dir1/*.graphql dir2/*.graphql > schema.graphql

API

You can also import the package. The following example merges all files living in the data/types folder.

import fs from 'fs';
import path from 'path';
import { mergeStrings } from 'gql-merge';

const typesDir = path.resolve(__dirname, 'data/types');
const typeFiles = fs.readdirSync(typesDir);
const types = typeFiles.map(file => fs.readFileSync(path.join(typesDir, file), 'utf-8'));
const typeDefs = mergeStrings(types);

More detailed docs coming soon.

mergeFileGlob

mergeFilePaths

mergeStrings

mergeString

mergeAst