feat(airtable): add airtable integration

packages/backend/src/apps/airtable/auth/generate-auth-url.js

@@ -0,0 +1,38 @@
+import crypto from 'crypto';
+import { URLSearchParams } from 'url';
+import authScope from '../common/auth-scope.js';
+
+export default async function generateAuthUrl($) {
+  const oauthRedirectUrlField = $.app.auth.fields.find(
+    (field) => field.key == 'oAuthRedirectUrl'
+  );
+  const redirectUri = oauthRedirectUrlField.value;
+  const state = crypto.randomBytes(100).toString('base64url');
+  const codeVerifier = crypto.randomBytes(96).toString('base64url');
+  const codeChallenge = crypto
+    .createHash('sha256')
+    .update(codeVerifier)
+    .digest('base64')
+    .replace(/=/g, '')
+    .replace(/\+/g, '-')
+    .replace(/\//g, '_');
+
+  const searchParams = new URLSearchParams({
+    client_id: $.auth.data.clientId,
+    redirect_uri: redirectUri,
+    response_type: 'code',
+    scope: authScope.join(' '),
+    state,
+    code_challenge: codeChallenge,
+    code_challenge_method: 'S256',
+  });
+
+  const url = `https://airtable.com/oauth2/v1/authorize?${searchParams.toString()}`;
+
+  await $.auth.set({
+    url,
+    originalCodeChallenge: codeChallenge,
+    originalState: state,
+    codeVerifier,
+  });
+}