introspectPrismicGraphql.js

const fetch = require("node-fetch");
const fs = require("fs");
const restUrl = "https://thec3.cdn.prismic.io/api/v2";
const graphqlUrl = "https://thec3.prismic.io/graphql";
const resultsFileName = "prismicIntrospectionResults";

fetch(`${restUrl}`)
  .then((response) => response.json())
  .then((data) => {
    const masterRef = data.refs.find((response) => response.id === "master");
    if (!masterRef) return;

    fetch(
      `${graphqlUrl}?query=%7B%20__schema%20%7B%20types%20%7B%20kind%20name%20possibleTypes%20%7B%20name%20%7D%20%7D%20%7D%20%7D`,
      {
        headers: {
          "prismic-ref": masterRef.ref,
        },
      }
    )
      .then((result) => result.json())
      .then((result) => {
        try {
          // here we're filtering out any type information unrelated to unions or interfaces
          const filteredData = result.data.__schema.types.filter((type) => type.possibleTypes !== null);

          result.data.__schema.types = filteredData;

          writeFile(result.data);
        } catch (error) {
          console.log(error);
        }
      });
  });
const writeFile = (data) => {
  fs.writeFileSync(`./${resultsFileName}.json`, JSON.stringify(data), (error) => {
    if (error) {
      console.error("Error writing fragmentTypes file", error);
    } else {
      console.log("Fragment types successfully extracted!");
    }
  });
};