@0xaio/react-scripts/scripts/get-schema.js

'use strict';

const fetch = require("node-fetch");
const fs = require("fs");

const {
  buildClientSchema,
  introspectionQuery,
  printSchema
} = require("graphql/utilities");
const chalk = require("chalk");

function isURL(str) {
  const urlRegex =
    "^(?!mailto:)(?:(?:http|https|ftp)://)(?:\\S+(?::\\S*)?@)?(?:(?:(?:[1-9]\\d?|1\\d\\d|2[01]\\d|22[0-3])(?:\\.(?:1?\\d{1,2}|2[0-4]\\d|25[0-5])){2}(?:\\.(?:[0-9]\\d?|1\\d\\d|2[0-4]\\d|25[0-4]))|(?:(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)(?:\\.(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)*(?:\\.(?:[a-z\\u00a1-\\uffff]{2,})))|localhost|django)(?::\\d{2,5})?(?:(/|\\?|#)[^\\s]*)?$";
  const url = new RegExp(urlRegex, "i");
  return str.length < 2083 && url.test(str)
}

const url = process.argv[3];

const saveJson = process.argv[4] === 'json';

if (!url) {
  console.log("Usage: get-schema " + chalk.green("url"));
  console.log("  " + chalk.green("url") + " is your graphql server address");
  process.exit()
}

if (!isURL(url)) {
  console.log(chalk.red(url) + " is not a valid url");
  process.exit(1)
}

console.log("Downloading for url: " + chalk.green(url));

fetch(url, {
  method: "POST",
  headers: {
    Accept: "application/json",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({query: introspectionQuery})
})
  .then(res => res.json())
  .then(res => {
    console.log(res);
    console.log("schema.graphql has downloaded and saved");
    if (saveJson) {
      const jsonString = JSON.stringify(res.data);
      console.log("schema.json has been saved");
      fs.writeFileSync("schema.json", jsonString)
    }
    const schemaString = printSchema(buildClientSchema(res.data));
    fs.writeFileSync("schema.graphql", schemaString)
  })
  .catch(e => {
    console.log(chalk.red("\nError:"));
    console.error(e);
    process.exit(1)
  });