For the weird unreachble graphql-codegen execution, I created a tiny proxy to fetch schema from a micro service on railway.app as a proxy, let it get the schema for you:

Two EnvVars to fill

1 HASURA_ADMIN_KEY : the hasura admin secret key.

2 HASURA_END_POINT : the hasura endpoint.

Setup public network

After deployment, set the public network in the instance setting panel, set the port to 3000, because we serve it on 3000 with bun.

Create a watcher

Now you have a endpoint url like :

https://something.up.railway.app/

I use @parcel/watcher to create a simple watcher, here are the must have packages:

bun add @graphql-codegen/cli @parcel/watcher

watcher.ts

import { subscribe } from '@parcel/watcher';
import { exec } from 'child_process';
import { promisify } from 'util';
import path from 'path';
import fs from 'fs';

const execAsync = promisify(exec);

async function runCommands() {
  try {
    const updateResult = await fetch(
      'https://something.up.railway.app/update',
      { method: 'POST' }
    );
    const updateData = await updateResult.text();
    console.log(updateData);
    const result = await fetch('https://something.up.railway.app/graphql');
    const data = await result.text();
    const filePath = path.join(__dirname, 'schema.graphql');

    fs.writeFileSync(filePath, data, 'utf8');
    console.log('Schema reloaded');

    await execAsync('bun graphql-codegen --config codegen.ts');
    console.log('Code generated');
  } catch (error) {
    console.error('Error executing commands:', error);
  }
}

// Watch for changes in *.tsx files
subscribe('./src', async (err, events) => {
  if (err) {
    console.error('Error watching files:', err);
    return;
  }

  for (const event of events) {
    if (event.path.endsWith('.tsx')) {
      console.log(`Detected change in ${event.path}`);
      await runCommands();
    }
  }
})
  .then(() => {
    console.log('Watching for .tsx file changes...');
  })
  .catch((err) => {
    console.error('Error setting up watcher:', err);
  });

Start the watcher

bun run watcher.ts

Modify any of your .tsx file and save:

Detected change in App.tsx
Schema updated successfully!
Schema reloaded
Code generated