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@^15/utilities/printSchema.js with AppSync specific options added.
2. convertSchemas(schemas: [string]) takes an array of GraphQL SDL string and converts them into one single AppSync comptaible schema.

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 glob = require("fast-glob");
const { promises: fs } = require("fs");
const { convertSchemas } = require("appsync-schema-converter");

const SCHEMA_PATH = "./schema.graphql";

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

  schemas = await glob(`${__dirname}/schemas/**/*.graphql`);
  schemas = await Promise.all(schemas.map((schema) => fs.readFile(schema, { encoding: "utf-8" })));
  schemas = await convertSchemas(schemas, {
    commentDescriptions: true,
    includeDirectives: true,
    includeEnumDescriptions: false,
    interfaceSeparator: ", ",
  });
  // Or use the simplified version: convertAppSyncSchemas(schemas);

  await fs.writeFile(SCHEMA_PATH, schemas);

  return SCHEMA_PATH;
};

Contributors

• Vicary Archangel (@vicary)
• Andy Fu (@andyfu84)
• Sylvain Simao (@maoosi)