Support for OAuth 2.0 (#5)

plugins/auth-oauth2/src/grants/authorizationCode.ts

@@ -0,0 +1,126 @@
+import { Context } from '@yaakapp/api';
+import { createHash, randomBytes } from 'node:crypto';
+import { getAccessToken } from '../getAccessToken';
+import { getOrRefreshAccessToken } from '../getOrRefreshAccessToken';
+import { AccessToken, storeToken } from '../store';
+
+export const PKCE_SHA256 = 'S256';
+export const PKCE_PLAIN = 'plain';
+export const DEFAULT_PKCE_METHOD = PKCE_SHA256;
+
+export async function getAuthorizationCode(
+  ctx: Context,
+  contextId: string,
+  {
+    authorizationUrl: authorizationUrlRaw,
+    accessTokenUrl,
+    clientId,
+    clientSecret,
+    redirectUri,
+    scope,
+    state,
+    credentialsInBody,
+    pkce,
+  }: {
+    authorizationUrl: string;
+    accessTokenUrl: string;
+    clientId: string;
+    clientSecret: string;
+    redirectUri: string | null;
+    scope: string | null;
+    state: string | null;
+    credentialsInBody: boolean;
+    pkce: {
+      challengeMethod: string | null;
+      codeVerifier: string | null;
+    } | null;
+  },
+): Promise<AccessToken> {
+  const token = await getOrRefreshAccessToken(ctx, contextId, {
+    accessTokenUrl,
+    scope,
+    clientId,
+    clientSecret,
+    credentialsInBody,
+  });
+  if (token != null) {
+    return token;
+  }
+
+  const authorizationUrl = new URL(`${authorizationUrlRaw ?? ''}`);
+  authorizationUrl.searchParams.set('response_type', 'code');
+  authorizationUrl.searchParams.set('client_id', clientId);
+  if (redirectUri) authorizationUrl.searchParams.set('redirect_uri', redirectUri);
+  if (scope) authorizationUrl.searchParams.set('scope', scope);
+  if (state) authorizationUrl.searchParams.set('state', state);
+  if (pkce) {
+    const verifier = pkce.codeVerifier || createPkceCodeVerifier();
+    const challengeMethod = pkce.challengeMethod || DEFAULT_PKCE_METHOD;
+    authorizationUrl.searchParams.set('code_challenge', createPkceCodeChallenge(verifier, challengeMethod));
+    authorizationUrl.searchParams.set('code_challenge_method', challengeMethod);
+  }
+
+  return new Promise(async (resolve, reject) => {
+    const authorizationUrlStr = authorizationUrl.toString();
+    console.log('Authorizing', authorizationUrlStr);
+    let { close } = await ctx.window.openUrl({
+      url: authorizationUrlStr,
+      label: 'oauth-authorization-url',
+      async onNavigate({ url: urlStr }) {
+        const url = new URL(urlStr);
+        if (url.searchParams.has('error')) {
+          return reject(new Error(`Failed to authorize: ${url.searchParams.get('error')}`));
+        }
+        const code = url.searchParams.get('code');
+        if (!code) {
+          return; // Could be one of many redirects in a chain, so skip it
+        }
+
+        // Close the window here, because we don't need it anymore!
+        close();
+
+        const response = await getAccessToken(ctx, {
+          grantType: 'authorization_code',
+          accessTokenUrl,
+          clientId,
+          clientSecret,
+          scope,
+          credentialsInBody,
+          params: [
+            { name: 'code', value: code },
+            ...(redirectUri ? [{ name: 'redirect_uri', value: redirectUri }] : []),
+          ],
+        });
+
+        try {
+          resolve(await storeToken(ctx, contextId, response));
+        } catch (err) {
+          reject(err);
+        }
+      },
+    });
+  });
+}
+
+function createPkceCodeVerifier() {
+  return encodeForPkce(randomBytes(32));
+}
+
+function createPkceCodeChallenge(verifier: string, method: string) {
+  if (method === 'plain') {
+    return verifier;
+  }
+
+  const hash = encodeForPkce(createHash('sha256').update(verifier).digest());
+  return hash
+    .replace(/=/g, '')  // Remove padding '='
+    .replace(/\+/g, '-') // Replace '+' with '-'
+    .replace(/\//g, '_'); // Replace '/' with '_'
+}
+
+function encodeForPkce(bytes: Buffer) {
+  return bytes.toString('base64')
+    .replace(/=/g, '')  // Remove padding '='
+    .replace(/\+/g, '-') // Replace '+' with '-'
+    .replace(/\//g, '_'); // Replace '/' with '_'
+}