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Express

Express is a popular node.js web server library. Mocks loaded into a GraphQLHandler can be integrated with express, via @graphql-mocks/network-express, to provide a live running server. This is useful when needing a live endpoint to test against or hosting mocks to share with others.

Installation​

Install the express and @graphql-mocks/network-express npm packages.

# npm
npm install --save-dev express @graphql-mocks/network-express

# yarn
yarn add --dev express @graphql-mocks/network-express

# pnpm
pnpm add --save-dev express @graphql-mocks/network-express

Usage​

Use expressMiddleware from @graphql-mocks/network-express as an application-level middleware or router middleware.

This example sets up a file server.js using an express server with the expressMiddleware as an application-middleware, listening on port 8080.

// server.js

const { GraphQLHandler } = require('graphql-mocks');
const { expressMiddleware } = require('@graphql-mocks/network-express');
const express = require('express');

const graphqlHandler = new GraphQLHandler({
  dependencies: { graphqlSchema }
};

const app = express();
app.post('/graphql', expressMiddleware(graphqlHandler));

const port = 8080;
app.listen(port);

Start the express app.

node server

The server will now be responding to graphql POST requests at http://localhost:8080/graphql.

For example, making a request using fetch (in the browser or via node-fetch)

fetch('http://localhost:8080/graphql, {
  method: 'POST',
  body: JSON.stringify({
    // required
    query: `
      query {
        # graphql query
      }
    `,

    // optional
    variables: {},

    // optional
    operationName: 'OperationName'
  })
}).then(async (response) => {
  // get the final json payload
  const result = await response.json();
  return result;
});

See the GraphQL docs for details on these body parameters, and making http requests.

Resolver Context​

The express request and response objects are available on the resolver context argument, under the express property.

function resolver(parent, args, context, info) {
  const { req, res } = context.express;
}

API Documentation​

See the API Documentation for types and more details.