mocking-a-graphql-server.md

Mocking a graphql service

To mock a graphql service you can use mock-server in combination with apollographql/graphql-tools (which actually does the hard work of creating a graphql mock resolver from a graphql schema).

To do so, create a mock-server/graphql directory, and put your API schema definition file inside of it:

# mock-server/graphql/schema.graphql
type Query {
  greeting: String
}

schema {
  query: Query
}

Then write a handler for the POST /graphql route:

// mock-server/graphql/post.js
const { readFileSync } = require("fs");
const { graphqlExpress } = require("graphql-server-express");
const graphqlTools = require("graphql-tools");

const schema = graphqlTools.makeExecutableSchema({
  typeDefs: [readFileSync(`${__dirname}/schema.graphql`, "utf8")],
});
graphqlTools.addMockFunctionsToSchema({ schema });
module.exports = graphqlExpress({ schema });