graphql-loader

Instantiate a GraphQL Schema by loading GraphQL Schema Language files based on a glob pattern

• Allows creation of GraphQL Schema via GraphQL schema language shorthand
• Supports splitting the schema into modules
• Parse and validate schema files
• Load GraphQL files from different modules and merge them into a single GraphQL Schema

Installation

npm install --save graphql @creditkarma/graphql-loader

Usage

Given the following files

schema/schema.graphql

schema {
  query: RootQuery
}

schema/rootQuery.graphql

type RootQuery {
  testString: String
}

loadSchema

Given a GLOB pattern, it will load all the content of the files matching the GLOB, combine them together and return a GraphQL Schema

Create a schema using promises:

const loader = require('@creditkarma/graphql-loader')

loader.loadSchema('./schema/*.graphql').then((schema) => {
  console.log(schema.getQueryType().toString())
})

Create a schema with a callback:

const loader = require('@creditkarma/graphql-loader')

loader.loadSchema('./schema/*.graphql', (err, schema) => {
  console.log(schema.getQueryType().toString())
})

Create a schema using sync:

const loader = require('@creditkarma/graphql-loader')

const schema = loader.loadSchema.sync('./schema/*.graphql')
console.log(schema.getQueryType().toString())

executableSchemaFromModules

Given an array of GraphQL Modules or functions that returns a GraphQL Module or Promise, merge the documents and resolvers together and return an executable GraphQL Schema

GraphQL modules are comprised of a document node and resolvers to provide away to decompose a GraphQL server into stand alone Node.js modules. These modules expose a DocumentNode because document nodes are valid GraphQL segments that are not required to be a complete valid schema.

It is required that the combination of GraphQLModules results in a completely valid GraphQLSchema.

const modules = [
  () => loadDocument('./fixtures/user/**/*.graphql').then((document) => ({ document, resolvers: {}})),
  () => loadDocument('./fixtures/swapi/**/*.graphql').then((document) => ({ document, resolvers: {}})),
]
executableSchemaFromModules(modules).then((schema) => {
  console.log(schema.getQueryType().toString())
})

loadDocument

Given a GLOB pattern, load the matching files, combine them together and return a GraphQL AST in the form of a DocumentNode. The document node will be parsed and validate but doesn't have to meet all the requirements of a full schema definition. For example, it is possible to just load several files with only types defined. NOTE: You must use a DocumentNode with the combineDocuments function

Load several GraphQL files into a single DocumentNode

const loader = require('@creditkarma/graphql-loader')

loader.loadDocument('./schema/*.graphql').then((doc) => {
  console.log(doc)
})

combineDocuments

Given an array of DocumentNodes, merge them together and return a GraphQLSchema

• Any duplicate Type definitions will be merged by concatenating their fields
• Any duplicate Schema definitions will be merged by concatenating their operations

Combine several documents into a GraphqlSchema

const loader = require('@creditkarma/graphql-loader')

Promise.all(
  loader.loadDocument('./ships/graphql/**/*.graphql'),
  loader.loadDocument('./planets/graphql/**/*.graphql')
).then((docs) => {
  const schema = combineDocuments(docs)
  console.log(schema.getQueryType().toString())
})

Development

Install dependencies with

npm install

Build

npm run build

Run test in watch mode

npm run test:watch

Contributing

For more information about contributing new features and bug fixes, see our Contribution Guidelines. External contributors must sign Contributor License Agreement (CLA)

License

This project is licensed under Apache License Version 2.0