Introspect and write GraphQL schema to file-system

write-schema.ts

import * as fs from 'fs';
import * as path from 'path';
import {
  getIntrospectionQuery,
  buildClientSchema,
  print
} 'graphql';

async function main() {
  const response = awaitfetch(process.env.GRAPHQL_API_URL, {
    method: 'post',
    headers: {
      Accept: 'application/json',
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({ query: getIntrospectionQuery() }),
  })
  const body = await response.json()
  const schema = buildClientSchema(body.data);
  const sdlString = print(schema);
  fs.writeFileSync(path.join(__dirname, 'schema.graphql'), sdlString);
}

main()