graphql-koa

GraphQL Koa Middleware

This is just a simple conversion of express-graphql for Koa. Almost all credit goes to the original express-graphql authors and contributors.

!!! This package has not been thoroughly tested. We are actively looking for contributors to help with testing.

Create a GraphQL HTTP server with Koa.

npm install --save graphql-koa

Install graphql-koa as middleware in your koa server (mount via koa-mount):

var graphqlHTTP = require('graphql-koa');
var mount = require('koa-mount');

var app = koa();

app.use( mount('/graphql', graphqlHTTP({ schema: MyGraphQLSchema })) )

Options

The graphqlHTTP function accepts the following options:

• schema: A GraphQLSchema instance from graphql-js. A schema must be provided.

• rootValue: A value to pass as the rootValue to the graphql() function from graphql-js.

• pretty: If true, any JSON response will be pretty-printed.

HTTP Usage

Once installed at a path, graphql-koa will accept requests with the parameters:

• query: A string GraphQL document to be executed.

• variables: The runtime values to use for any GraphQL query variables as a JSON object.

• operationName: If the provided query contains multiple named operations, this specifies which operation should be executed. If not provided, an 400 error will be returned if the query contains multiple named operations.

GraphQL will first look for each parameter in the URL's query-string:

/graphql?query=query+getUser($id:ID){user(id:$id){name}}&variables={"id":"4"}

If not found in the query-string, it will look in the POST request body.

If a previous middleware has already parsed the POST body, the request.body value will be used.

If the POST body has not yet been parsed, graphql-koa will interpret it depending on the provided Content-Type header.

• application/json: the POST body will be parsed as a JSON object of parameters.

• application/x-www-form-urlencoded: this POST body will be parsed as a url-encoded string of key-value pairs.

• application/graphql: The POST body will be parsed as GraphQL query string, which provides the query parameter.