appsync-schema-converter

AppSync Schema Converter

The sole purpose of this package is to convert modern GraphQL schemas into AppSync compatible version.

1. printSchema() is a copy of graphql@^14.4.2/utilities/schemaPrinter.js@printSchema with includesDirectives: Boolean option added.
2. convertSchemas(schemas: [string]) takes an array of GraphQL SDL string and converts them into one single AppSync comptaible schema.

My team only works with Apollo, so expects more care on that front.

If AppSync updates their ancient GraphQL engine, I am more than happy to ditch this package.

Serverless Framework

This package also made with serverless-appsync-plugin in mind, especially useful when merge-graphql-schemas was in your stack.

You make use of variables in JavaScript and write a little script to merge schemas into AppSync compatible one.

Based on your serverless-appsync-plugin settings, change this line in your serverless.yml.

custom:
  appSync:
    schema: ${file(schema.js):compile}

Then read and convert your schemas in schema.js@compile.

const { promisify } = require('util');
const glob = require('glob');
const { readFile, writeFile } = require('fs').promises;
const { convertSchemas } = require("appsync-schema-converter");

const SCHEMA_PATH = './schema.graphql';

module.exports.compile = async _ => {
  let schemas;

  schemas = await promisify(glob)(`${__dirname}/schemas/**/*.graphql`);
  schemas = await Promise.all(schemas.map(async schema => (await readFile(schema)).toString('utf8')));

  schemas = convertSchemas(schemas, {
    commentDescriptions: true,
    includeDirectives: true,
  });

  await writeFile(SCHEMA_PATH, schemas);

  return SCHEMA_PATH;
};

Contributors

• Vicary Archangel