GraphQL JIT

Why?

GraphQL-JS is a very well written runtime implementation of the latest GraphQL spec. However, by compiling to JS, V8 is able to create optimized code which yields much better performance.

Benchmarks

$ ts-node -T ./src/__benchmarks__/schema.benchmark.ts 
graphql-js x 3,873 ops/sec ±3.89% (74 runs sampled)
graphql-jit x 128,301 ops/sec ±1.79% (75 runs sampled)
Fastest is graphql-jit

$ ts-node -T ./src/__benchmarks__/schema-many-resolvers.benchmark.ts 
graphql-js x 5,458 ops/sec ±5.62% (70 runs sampled)
graphql-jit x 52,345 ops/sec ±3.95% (74 runs sampled)
Fastest is graphql-jit

Support

The goal is to support the June 2018 version of the GraphQL spec. At this moment, the only missing feature is support for the @skip and @include directives.

Differences to graphql-js

In order to achieve better performance, the compiler introduces some limitations. The main one is that all computed properties must have a resolver and only these can return a Promise.

Install

yarn add graphql-jit

Example

For complete working examples, check the examples/ directory

Create a schema

const typedefs = `
type Query {
  hello: string
}
`;
const resolvers = {
  Query: {
    hello() {
      return new Promise(resolve => setTimeout(() => resolve("World!"), 200));
    }
  }
};

const { makeExecutableSchema } = require("graphql");
const schema = makeExecutableSchema({ typedefs, resolvers });

Compile a Query

const query = `
{
  hello
}
`;
const { parse } = require("graphql");
const document = parse(query);

const { compileQuery, isCompiledQuery } = require("graphql-jit");
const compiledQuery = compileQuery(schema, document);
// check if the compilation is successful

if (!isCompiledQuery(compiledQuery)) {
  console.error(compiledQuery);
  throw new Error("Error compiling query");
}

Execute the Query

const executionResult = await compiledQuery.query();
console.log(executionResult);

API

compiledQuery = compileQuery(schema, document, operationName, compilerOptions)

Compiles the document AST, using an optional operationName and compiler options.

• schema {GraphQLSchema} - graphql-js schema object

• document {DocumentNode} - document query AST ,can be obtained by parse from graphql-js

• operationName {string} - optional operation name in case the document contains multiple queries/operations.

• compilerOptions {Object} - Configurable options on the agent pool

  • disableLeafSerialization {boolean, default: false} - disables leaf node serializers. The serializers validate the content of the field so this option should only be set to true if there are strong assurances that the values are valid.
  • customSerializers {Object as Map, default: {}} - Replace serializer functions for specific types. Can be used as a safer alternative for overly expensive
  • customJSONSerializer {boolean, default: false} - Whether to produce also a JSON serializer function using fast-json-stringify, otherwise the stringify function is just JSON.stringify

compiledQuery.compiled(root: any, context: any, variables: Maybe<{ [key: string]: any }>)

the compiled function that can be called with a root value, a context and the required variables.

compiledQuery.stringify(value: any)

the compiled function for producing a JSON string. It will be JSON.stringify unless compilerOptions.customJSONSerializer is true. The value argument should the return of the compiled GraphQL function.

LICENSE

MIT