Update storage trigger samples

functions/composer-storage-trigger/index.js

@@ -31,7 +31,7 @@ const FormData = require('form-data');
  * @param {!Object} event The Cloud Functions event.
  * @returns {Promise}
  */
-exports.triggerDag = function triggerDag(event) {
+exports.triggerDag = async event => {
   // Fill in your Composer environment information here.
 
   // The project that holds your function
@@ -50,23 +50,27 @@ exports.triggerDag = function triggerDag(event) {
   const BODY = {conf: JSON.stringify(event.data)};
 
   // Make the request
-  return authorizeIap(CLIENT_ID, PROJECT_ID, USER_AGENT).then(iap => {
+  try {
+    const iap = await authorizeIap(CLIENT_ID, PROJECT_ID, USER_AGENT);
+
     return makeIapPostRequest(
       WEBSERVER_URL,
       BODY,
       iap.idToken,
       USER_AGENT,
       iap.jwt
     );
-  });
+  } catch (err) {
+    throw new Error(err);
+  }
 };
 
 /**
  * @param {string} clientId The client id associated with the Composer webserver application.
  * @param {string} projectId The id for the project containing the Cloud Function.
  * @param {string} userAgent The user agent string which will be provided with the webserver request.
  */
-function authorizeIap(clientId, projectId, userAgent) {
+const authorizeIap = async (clientId, projectId, userAgent) => {
   const SERVICE_ACCOUNT = `${projectId}@appspot.gserviceaccount.com`;
   const JWT_HEADER = Buffer.from(
     JSON.stringify({alg: 'RS256', typ: 'JWT'})
@@ -76,89 +80,88 @@ function authorizeIap(clientId, projectId, userAgent) {
   let jwtClaimset = '';
 
   // Obtain an Oauth2 access token for the appspot service account
-  return fetch(
+  const res = await fetch(
     `http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/${SERVICE_ACCOUNT}/token`,
     {
       headers: {'User-Agent': userAgent, 'Metadata-Flavor': 'Google'},
     }
-  )
-    .then(res => res.json())
-    .then(tokenResponse => {
-      if (tokenResponse.error) {
-        return Promise.reject(tokenResponse.error);
-      }
-      const accessToken = tokenResponse.access_token;
-      const iat = Math.floor(new Date().getTime() / 1000);
-      const claims = {
-        iss: SERVICE_ACCOUNT,
-        aud: 'https://www.googleapis.com/oauth2/v4/token',
-        iat: iat,
-        exp: iat + 60,
-        target_audience: clientId,
-      };
-      jwtClaimset = Buffer.from(JSON.stringify(claims)).toString('base64');
-      const toSign = [JWT_HEADER, jwtClaimset].join('.');
-
-      return fetch(
-        `https://iam.googleapis.com/v1/projects/${projectId}/serviceAccounts/${SERVICE_ACCOUNT}:signBlob`,
-        {
-          method: 'POST',
-          body: JSON.stringify({
-            bytesToSign: Buffer.from(toSign).toString('base64'),
-          }),
-          headers: {
-            'User-Agent': userAgent,
-            Authorization: `Bearer ${accessToken}`,
-          },
-        }
-      );
-    })
-    .then(res => res.json())
-    .then(body => {
-      if (body.error) {
-        return Promise.reject(body.error);
-      }
-      // Request service account signature on header and claimset
-      const jwtSignature = body.signature;
-      jwt = [JWT_HEADER, jwtClaimset, jwtSignature].join('.');
-      const form = new FormData();
-      form.append('grant_type', 'urn:ietf:params:oauth:grant-type:jwt-bearer');
-      form.append('assertion', jwt);
-      return fetch('https://www.googleapis.com/oauth2/v4/token', {
-        method: 'POST',
-        body: form,
-      });
-    })
-    .then(res => res.json())
-    .then(body => {
-      if (body.error) {
-        return Promise.reject(body.error);
-      }
-      return {
-        jwt: jwt,
-        idToken: body.id_token,
-      };
-    });
-}
+  );
+  const tokenResponse = res.json();
+  if (tokenResponse.error) {
+    return Promise.reject(tokenResponse.error);
+  }
+
+  const accessToken = tokenResponse.access_token;
+  const iat = Math.floor(new Date().getTime() / 1000);
+  const claims = {
+    iss: SERVICE_ACCOUNT,
+    aud: 'https://www.googleapis.com/oauth2/v4/token',
+    iat: iat,
+    exp: iat + 60,
+    target_audience: clientId,
+  };
+  jwtClaimset = Buffer.from(JSON.stringify(claims)).toString('base64');
+  const toSign = [JWT_HEADER, jwtClaimset].join('.');
+
+  const blob = await fetch(
+    `https://iam.googleapis.com/v1/projects/${projectId}/serviceAccounts/${SERVICE_ACCOUNT}:signBlob`,
+    {
+      method: 'POST',
+      body: JSON.stringify({
+        bytesToSign: Buffer.from(toSign).toString('base64'),
+      }),
+      headers: {
+        'User-Agent': userAgent,
+        Authorization: `Bearer ${accessToken}`,
+      },
+    }
+  );
+  const blobJson = blob.json();
+  if (blobJson.error) {
+    return Promise.reject(blobJson.error);
+  }
+
+  // Request service account signature on header and claimset
+  const jwtSignature = blobJson.signature;
+  jwt = [JWT_HEADER, jwtClaimset, jwtSignature].join('.');
+  const form = new FormData();
+  form.append('grant_type', 'urn:ietf:params:oauth:grant-type:jwt-bearer');
+  form.append('assertion', jwt);
+
+  const token = await fetch('https://www.googleapis.com/oauth2/v4/token', {
+    method: 'POST',
+    body: form,
+  });
+  const tokenJson = token.json();
+  if (tokenJson.error) {
+    return Promise.reject(tokenJson.error);
+  }
+
+  return {
+    jwt: jwt,
+    idToken: tokenJson.id_token,
+  };
+};
 
 /**
  * @param {string} url The url that the post request targets.
  * @param {string} body The body of the post request.
  * @param {string} idToken Bearer token used to authorize the iap request.
  * @param {string} userAgent The user agent to identify the requester.
  */
-function makeIapPostRequest(url, body, idToken, userAgent) {
-  return fetch(url, {
+const makeIapPostRequest = async (url, body, idToken, userAgent) => {
+  const res = await fetch(url, {
     method: 'POST',
     headers: {
       'User-Agent': userAgent,
       Authorization: `Bearer ${idToken}`,
     },
     body: JSON.stringify(body),
-  }).then(res => {
-    if (!res.ok) {
-      return res.text().then(body => Promise.reject(body));
-    }
   });
-}
+
+  if (!res.ok) {
+    const err = await res.text();
+    throw new Error(err);
+  }
+};
 // [END composer_trigger]

functions/composer-storage-trigger/test/index.test.js

@@ -39,14 +39,15 @@ it('Handles error in JSON body', async () => {
   const expectedMsg = 'Something bad happened.';
   const bodyJson = {error: expectedMsg};
   const body = {
-    json: sinon.stub().resolves(bodyJson),
+    json: sinon.stub().returns(bodyJson),
   };
   const sample = getSample(sinon.stub().resolves(body));
 
   try {
     await sample.program.triggerDag(event);
+    assert.fail('No error thrown');
   } catch (err) {
-    assert.strictEqual(new RegExp(/Something bad happened/).test(err), true);
+    assert.deepStrictEqual(err, new Error('Something bad happened.'));
   }
 });
 
@@ -85,6 +86,6 @@ it('Handles error in IAP response.', async () => {
   try {
     await sample.program.triggerDag(event);
   } catch (err) {
-    assert.strictEqual(err, expectedMsg);
+    assert.deepStrictEqual(err, new Error(expectedMsg));
   }
 });