From ed745a3b0fade12045dab135b359085866bc7ee6 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Tue, 24 Apr 2018 16:50:26 -0700
Subject: [PATCH 01/17] Add inline samples

---
 functions/helloworld/.gcloudignore |  16 ++++
 functions/helloworld/index.js      |  41 ++++++++++
 functions/http/index.js            |  72 +++++++++++++++++
 functions/http/package.json        |   1 +
 functions/tips/index.js            | 124 +++++++++++++++++++++++++++++
 functions/tips/package.json        |  36 +++++++++
 6 files changed, 290 insertions(+)
 create mode 100644 functions/helloworld/.gcloudignore
 create mode 100644 functions/tips/index.js
 create mode 100644 functions/tips/package.json

diff --git a/functions/helloworld/.gcloudignore b/functions/helloworld/.gcloudignore
new file mode 100644
index 0000000000..ccc4eb240e
--- /dev/null
+++ b/functions/helloworld/.gcloudignore
@@ -0,0 +1,16 @@
+# This file specifies files that are *not* uploaded to Google Cloud Platform
+# using gcloud. It follows the same syntax as .gitignore, with the addition of
+# "#!include" directives (which insert the entries of the given .gitignore-style
+# file at that point).
+#
+# For more information, run:
+#   $ gcloud topic gcloudignore
+#
+.gcloudignore
+# If you would like to upload your .git directory, .gitignore file or files
+# from your .gitignore file, remove the corresponding line
+# below:
+.git
+.gitignore
+
+node_modules
diff --git a/functions/helloworld/index.js b/functions/helloworld/index.js
index 3eda309167..8aeda8654c 100644
--- a/functions/helloworld/index.js
+++ b/functions/helloworld/index.js
@@ -170,3 +170,44 @@ exports.helloTemplate = (req, res) => {
   res.send(html).end();
 };
 // [END functions_helloworld_template]
+
+/**
+ * HTTP Cloud Function that demonstrates
+ * how to catch errors of different types.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.helloErrorTypes = (req, res) => {
+  // [START functions_helloworld_error_object]
+  try {
+    // Throw an Error object (to simulate a GCP API failure)
+    throw new Error('Error object!');
+  } catch (err) {
+    // err is already an Error object
+    console.error(err);
+  }
+  // [END functions_helloworld_error_object]
+
+  /* eslint-disable no-throw-literal */
+  // [START functions_helloworld_error_unknown]
+  try {
+    // Throw an unknown error type
+    if (Date.now() % 2 === 0) {
+      throw 'Error string!';
+    } else {
+      throw new Error('Error object!');
+    }
+  } catch (err) {
+    // Determine the error type
+    if (err instanceof Error) {
+      console.error(err);
+    } else {
+      console.error(new Error(err));
+    }
+  }
+  // [END functions_helloworld_error_unknown]
+  /* eslint-enable no-throw-literal */
+
+  res.end();
+};
diff --git a/functions/http/index.js b/functions/http/index.js
index 317994e015..db0c941bfa 100644
--- a/functions/http/index.js
+++ b/functions/http/index.js
@@ -105,3 +105,75 @@ exports.helloHttp = (req, res) => {
   }
 };
 // [END functions_http_method]
+
+// [START functions_http_xml]
+/**
+ * Parses a document of type 'text/xml'
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.parseXML = (req, res) => {
+  // Convert the request to a Buffer and a string
+  // Use whichever one is accepted by your XML parser
+  let data = req.rawBody;
+  let xmlData = data.toString();
+
+  const parseString = require('xml2js').parseString;
+
+  parseString(xmlData, (err, result) => {
+    if (err) {
+      console.error(err);
+      res.status(500).end();
+      return;
+    }
+    res.send(result);
+  });
+};
+// [END functions_http_xml]
+
+// [START functions_http_form_data]
+/**
+ * Parses a 'multipart/form-data' upload request
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+const path = require('path');
+const os = require('os');
+const fs = require('fs');
+const Busboy = require('busboy');
+
+exports.uploadFile = (req, res) => {
+  if (req.method === 'POST') {
+    const busboy = new Busboy({ headers: req.headers });
+
+    // This object will accumulate all the uploaded files, keyed by their name.
+    const uploads = {};
+    const tmpdir = os.tmpdir();
+
+    // This callback will be invoked for each file uploaded.
+    busboy.on('file', (fieldname, file, filename) => {
+      // Note: os.tmpdir() - and any files in it - must fit in memory.
+      const filepath = path.join(tmpdir, filename);
+      uploads[fieldname] = filepath;
+      file.pipe(fs.createWriteStream(filepath));
+    });
+
+    // This callback will be invoked after all uploaded files are saved.
+    busboy.on('finish', () => {
+      // TODO(developer): Process uploaded files here
+      for (const name in uploads) {
+        const file = uploads[name];
+        fs.unlinkSync(file);
+      }
+      res.send();
+    });
+
+    req.pipe(busboy);
+  } else {
+    // Ignore non-POST requests
+    res.status(405).send();
+  }
+};
+// [END functions_http_form_data]
diff --git a/functions/http/package.json b/functions/http/package.json
index 18638d347b..5a82ee97e2 100644
--- a/functions/http/package.json
+++ b/functions/http/package.json
@@ -23,6 +23,7 @@
     "sinon": "4.4.2"
   },
   "dependencies": {
+    "busboy": "^0.2.14",
     "safe-buffer": "5.1.1"
   },
   "cloud-repo-tools": {
diff --git a/functions/tips/index.js b/functions/tips/index.js
new file mode 100644
index 0000000000..1e70c80745
--- /dev/null
+++ b/functions/tips/index.js
@@ -0,0 +1,124 @@
+/**
+ * Copyright 2016, Google, Inc.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+const Buffer = require('safe-buffer').Buffer;
+
+const lightComputation = () => {
+  const numbers = [1,2,3,4,5,6,7,8,9];
+  return numbers.reduce((t, x) => t + x)
+}
+
+const heavyComputation = () => {
+  // Multiplication is more computationally expensive than addition
+  const numbers = [1,2,3,4,5,6,7,8,9];
+  return numbers.reduce((t, x) => t * x)
+}
+
+const functionSpecificComputation = heavyComputation;
+const fileWideComputation = lightweightComputation;
+
+// [START functions_scopes]
+// Global (instance-wide) scope
+// This computation runs at instance cold-start
+const instanceVar = heavyComputation();
+
+/**
+ * Sample HTTP Cloud Function.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.scopeDemo = (req, res) => {
+    // Per-function scope
+    // This computation runs every time this function is called
+    const functionVar = lightweightComputation();
+
+    res.end(`Per instance: ${instanceVar}, per function: ${functionVar}`);
+}
+// [END functions_scopes]
+
+// [START functions_lazy_globals]
+// This value is always initialized, which happens at cold-start
+const nonLazyGlobal = fileWideComputation();
+let lazyGlobal;
+
+/**
+ * Sample HTTP Cloud Function.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.lazyGlobals = (req, res) => {
+  // This value is initialized only if (and when) the function is called
+  lazyGlobal = lazyGlobal || functionSpecificComputation();
+
+  res.end(`Lazy global: ${lazyGlobal}, non-lazy global: ${nonLazyGlobal}`);
+}
+// [END functions_lazy_globals]
+
+// [START functions_ephemeral_connection]
+// [START functions_cached_connection]
+const http = require('http');
+// [END functions_ephemeral_connection]
+const agent = new http.Agent({keepAlive: true});
+// [END functions_cached_connection]
+
+// TODO(ace-n) make sure this import works as intended
+// [START functions_ephemeral_connection]
+exports.ephemeralConnection = (req, res) => {
+  req = http.request({
+    host: '<HOST>',
+    port: 80,
+    path: '<PATH>',
+    method: 'GET',
+  }, res => {
+    let rawData = '';
+    res.setEncoding('utf8');
+    res.on('data', chunk => { rawData += chunk; });
+    res.on('end', () => {
+      response.status(200).send(`Data: ${rawData}`);
+    });
+  });
+  req.on('error', (e) => {
+    response.status(500).send(`Error: ${e.message}`);
+  });
+  req.end();
+};
+// [END functions_ephemeral_connection]
+
+// [START functions_cached_connection]
+exports.cachedConnection = (request, response) => {
+  req = http.request({
+    host: '',
+    port: 80,
+    path: '',
+    method: 'GET',
+    agent: agent,
+  }, res => {
+    let rawData = '';
+    res.setEncoding('utf8');
+    res.on('data', chunk => { rawData += chunk; });
+    res.on('end', () => {
+      response.status(200).send(`Data: ${rawData}`);
+    });
+  });
+  req.on('error', e => {
+    response.status(500).send(`Error: ${e.message}`);
+  });
+  req.end();
+};
+// [END functions_cached_connection]
diff --git a/functions/tips/package.json b/functions/tips/package.json
new file mode 100644
index 0000000000..a3cfe24660
--- /dev/null
+++ b/functions/tips/package.json
@@ -0,0 +1,36 @@
+{
+  "name": "nodejs-docs-samples-functions-tips",
+  "version": "0.0.1",
+  "private": true,
+  "license": "Apache-2.0",
+  "author": "Google Inc.",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
+  },
+  "engines": {
+    "node": ">=6.14.0"
+  },
+  "scripts": {
+    "lint": "repo-tools lint",
+    "pretest": "npm run lint",
+  },
+  "dependencies": {
+    "safe-buffer": "5.1.1"
+  },
+  "devDependencies": {
+    "@google-cloud/nodejs-repo-tools": "2.2.5",
+    "ava": "0.25.0",
+  },
+  "cloud-repo-tools": {
+    "requiresKeyFile": true,
+    "requiresProjectId": true,
+    "requiredEnvVars": [
+      "BASE_URL",
+      "GCF_REGION",
+      "TOPIC",
+      "BUCKET",
+      "FUNCTIONS_CMD"
+    ]
+  }
+}

From 3ec59a13c2dd276c161e2b909da76c269fd2e76b Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Tue, 24 Apr 2018 17:17:22 -0700
Subject: [PATCH 02/17] Add getSignedUrl sample

---
 functions/http/index.js | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/functions/http/index.js b/functions/http/index.js
index db0c941bfa..2d806c6053 100644
--- a/functions/http/index.js
+++ b/functions/http/index.js
@@ -177,3 +177,42 @@ exports.uploadFile = (req, res) => {
   }
 };
 // [END functions_http_form_data]
+
+// [START functions_http_signed_url]
+const storage = require('@google-cloud/storage')();
+
+/**
+ * HTTP function that generates a signed URL
+ * The signed URL can be used to upload files to Google Cloud Storage (GCS)
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.getSignedUrl = (req, res) => {
+  if(req.method === 'POST') {
+    // TODO(developer) check that the user is authorized to upload
+
+    // Get a reference to the destination file in GCS
+    const file = storage.bucket('my-bucket').file(req.body.filename);
+
+    // Create a temporary upload URL
+    const expiresAtMs = Date.now() + 300000; // Link expires in 5 minutes
+    const config = {
+      action: 'write',
+      expires: expiresAtMs,
+      contentType: req.body.contentType
+    };
+
+    file.getSignedUrl(config, function(err, url) {
+      if (err) {
+        console.error(err);
+        res.status(500).end();
+        return;
+      }
+      res.send(url);
+    });
+  } else {
+      res.status(405).end();
+  }
+}
+// [END functions_http_signed_url]

From 0f31a808d2176036b19f8f8df6dbf2a665457f05 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Tue, 24 Apr 2018 17:22:57 -0700
Subject: [PATCH 03/17] Update tips region tags

---
 functions/tips/index.js | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/functions/tips/index.js b/functions/tips/index.js
index 1e70c80745..2015fe9a8c 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -31,7 +31,7 @@ const heavyComputation = () => {
 const functionSpecificComputation = heavyComputation;
 const fileWideComputation = lightweightComputation;
 
-// [START functions_scopes]
+// [START functions_tips_scopes]
 // Global (instance-wide) scope
 // This computation runs at instance cold-start
 const instanceVar = heavyComputation();
@@ -49,9 +49,9 @@ exports.scopeDemo = (req, res) => {
 
     res.end(`Per instance: ${instanceVar}, per function: ${functionVar}`);
 }
-// [END functions_scopes]
+// [END functions_tips_scopes]
 
-// [START functions_lazy_globals]
+// [START functions_tips_lazy_globals]
 // This value is always initialized, which happens at cold-start
 const nonLazyGlobal = fileWideComputation();
 let lazyGlobal;
@@ -68,17 +68,17 @@ exports.lazyGlobals = (req, res) => {
 
   res.end(`Lazy global: ${lazyGlobal}, non-lazy global: ${nonLazyGlobal}`);
 }
-// [END functions_lazy_globals]
+// [END functions_tips_lazy_globals]
 
-// [START functions_ephemeral_connection]
-// [START functions_cached_connection]
+// [START functions_tips_ephemeral_connection]
+// [START functions_tips_cached_connection]
 const http = require('http');
-// [END functions_ephemeral_connection]
+// [END functions_tips_ephemeral_connection]
 const agent = new http.Agent({keepAlive: true});
-// [END functions_cached_connection]
+// [END functions_tips_cached_connection]
 
 // TODO(ace-n) make sure this import works as intended
-// [START functions_ephemeral_connection]
+// [START functions_tips_ephemeral_connection]
 exports.ephemeralConnection = (req, res) => {
   req = http.request({
     host: '<HOST>',
@@ -98,9 +98,9 @@ exports.ephemeralConnection = (req, res) => {
   });
   req.end();
 };
-// [END functions_ephemeral_connection]
+// [END functions_tips_ephemeral_connection]
 
-// [START functions_cached_connection]
+// [START functions_tips_cached_connection]
 exports.cachedConnection = (request, response) => {
   req = http.request({
     host: '',
@@ -121,4 +121,4 @@ exports.cachedConnection = (request, response) => {
   });
   req.end();
 };
-// [END functions_cached_connection]
+// [END functions_tips_cached_connection]

From fa3bd7c0eaa5bcf6ed2a103f6b157f02bcdb45d1 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Wed, 25 Apr 2018 15:15:41 -0700
Subject: [PATCH 04/17] Add retry samples

---
 functions/tips/index.js | 150 ++++++++++++++++++++++++++++++----------
 1 file changed, 112 insertions(+), 38 deletions(-)

diff --git a/functions/tips/index.js b/functions/tips/index.js
index 2015fe9a8c..88f690bff3 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -15,21 +15,19 @@
 
 'use strict';
 
-const Buffer = require('safe-buffer').Buffer;
-
 const lightComputation = () => {
-  const numbers = [1,2,3,4,5,6,7,8,9];
-  return numbers.reduce((t, x) => t + x)
-}
+  const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9];
+  return numbers.reduce((t, x) => t + x);
+};
 
 const heavyComputation = () => {
   // Multiplication is more computationally expensive than addition
-  const numbers = [1,2,3,4,5,6,7,8,9];
-  return numbers.reduce((t, x) => t * x)
-}
+  const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9];
+  return numbers.reduce((t, x) => t * x);
+};
 
 const functionSpecificComputation = heavyComputation;
-const fileWideComputation = lightweightComputation;
+const fileWideComputation = lightComputation;
 
 // [START functions_tips_scopes]
 // Global (instance-wide) scope
@@ -43,12 +41,12 @@ const instanceVar = heavyComputation();
  * @param {Object} res Cloud Function response context.
  */
 exports.scopeDemo = (req, res) => {
-    // Per-function scope
-    // This computation runs every time this function is called
-    const functionVar = lightweightComputation();
+  // Per-function scope
+  // This computation runs every time this function is called
+  const functionVar = lightComputation();
 
-    res.end(`Per instance: ${instanceVar}, per function: ${functionVar}`);
-}
+  res.end(`Per instance: ${instanceVar}, per function: ${functionVar}`);
+};
 // [END functions_tips_scopes]
 
 // [START functions_tips_lazy_globals]
@@ -67,58 +65,134 @@ exports.lazyGlobals = (req, res) => {
   lazyGlobal = lazyGlobal || functionSpecificComputation();
 
   res.end(`Lazy global: ${lazyGlobal}, non-lazy global: ${nonLazyGlobal}`);
-}
+};
 // [END functions_tips_lazy_globals]
 
-// [START functions_tips_ephemeral_connection]
-// [START functions_tips_cached_connection]
+// [START functions_tips_ephemeral_agent]
+// [START functions_tips_cached_agent]
 const http = require('http');
-// [END functions_tips_ephemeral_connection]
+// [END functions_tips_ephemeral_agent]
 const agent = new http.Agent({keepAlive: true});
 // [END functions_tips_cached_connection]
 
 // TODO(ace-n) make sure this import works as intended
-// [START functions_tips_ephemeral_connection]
-exports.ephemeralConnection = (req, res) => {
+// [START functions_tips_ephemeral_agent]
+/**
+ * HTTP Cloud Function that uses an ephemeral HTTP agent
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.ephemeralAgent = (req, res) => {
   req = http.request({
     host: '<HOST>',
     port: 80,
     path: '<PATH>',
-    method: 'GET',
-  }, res => {
+    method: 'GET'
+  }, resInner => {
     let rawData = '';
-    res.setEncoding('utf8');
-    res.on('data', chunk => { rawData += chunk; });
-    res.on('end', () => {
-      response.status(200).send(`Data: ${rawData}`);
+    resInner.setEncoding('utf8');
+    resInner.on('data', chunk => { rawData += chunk; });
+    resInner.on('end', () => {
+      res.status(200).send(`Data: ${rawData}`);
     });
   });
   req.on('error', (e) => {
-    response.status(500).send(`Error: ${e.message}`);
+    res.status(500).send(`Error: ${e.message}`);
   });
   req.end();
 };
-// [END functions_tips_ephemeral_connection]
+// [END functions_tips_ephemeral_agent]
 
-// [START functions_tips_cached_connection]
-exports.cachedConnection = (request, response) => {
+// [START functions_tips_cached_agent]
+/**
+ * HTTP Cloud Function that uses a cached HTTP agent
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.cachedAgent = (req, res) => {
   req = http.request({
     host: '',
     port: 80,
     path: '',
     method: 'GET',
-    agent: agent,
-  }, res => {
+    agent: agent
+  }, resInner => {
     let rawData = '';
-    res.setEncoding('utf8');
-    res.on('data', chunk => { rawData += chunk; });
-    res.on('end', () => {
-      response.status(200).send(`Data: ${rawData}`);
+    resInner.setEncoding('utf8');
+    resInner.on('data', chunk => { rawData += chunk; });
+    resInner.on('end', () => {
+      res.status(200).send(`Data: ${rawData}`);
     });
   });
   req.on('error', e => {
-    response.status(500).send(`Error: ${e.message}`);
+    res.status(500).send(`Error: ${e.message}`);
   });
   req.end();
 };
-// [END functions_tips_cached_connection]
+// [END functions_tips_cached_agent]
+
+// [START functions_tips_infinite_retries]
+/**
+ * Background Cloud Function that only executes within
+ * a certain time period after the triggering event
+ *
+ * @param {object} event The Cloud Functions event.
+ * @param {function} callback The callback function.
+ */
+exports.avoidInfiniteRetries = (event, callback) => {
+  const eventAge = Date.now() - Date.parse(event.timestamp);
+  const eventMaxAge = 10000;
+
+  // Ignore events that are too old
+  if (eventAge > eventMaxAge) {
+    console.log(`Dropping event ${event} with age ${eventAge} ms.`);
+    callback();
+    return;
+  }
+
+  // Do what the function is supposed to do
+  console.log(`Processing event ${event} with age ${eventAge} ms.`);
+};
+// [END functions_tips_infinite_retries]
+
+// [START functions_tips_retry_promise]
+/**
+ * Background Cloud Function that demonstrates
+ * how to toggle retries using a callback
+ *
+ * @param {object} event The Cloud Functions event.
+ */
+exports.retryPromise = (event) => {
+  const tryAgain = false;
+
+  if (tryAgain) {
+    throw new Error(`Retrying...`);
+  } else {
+    return Promise.reject(new Error('Not retrying...'));
+  }
+};
+// [END functions_tips_retry_promise]
+
+// [START functions_tips_retry_callback]
+/**
+ * Background Cloud Function that demonstrates
+ * how to toggle retries using a promise
+ *
+ * @param {object} event The Cloud Functions event.
+ * @param {function} callback The callback function.
+ */
+exports.retryCallback = (event, callback) => {
+  const tryAgain = false;
+  const err = new Error('Error!');
+
+  if (tryAgain) {
+    console.error(`Retrying: ${err}`);
+    callback(err);
+  } else {
+    console.error(`Not retrying: ${err}`);
+    callback();
+  }
+};
+// [END functions_tips_retry_callback]

From 14e9ee6a21d58a71bef2346bae1e04c56eba5401 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Wed, 25 Apr 2018 15:19:36 -0700
Subject: [PATCH 05/17] Fix comments

---
 functions/tips/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/functions/tips/index.js b/functions/tips/index.js
index 88f690bff3..7bb63bbd84 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -160,7 +160,7 @@ exports.avoidInfiniteRetries = (event, callback) => {
 // [START functions_tips_retry_promise]
 /**
  * Background Cloud Function that demonstrates
- * how to toggle retries using a callback
+ * how to toggle retries using a promise
  *
  * @param {object} event The Cloud Functions event.
  */
@@ -178,7 +178,7 @@ exports.retryPromise = (event) => {
 // [START functions_tips_retry_callback]
 /**
  * Background Cloud Function that demonstrates
- * how to toggle retries using a promise
+ * how to toggle retries using a callback
  *
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.

From b023e7934586765516815b55208801790bed3ae3 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Wed, 25 Apr 2018 16:04:25 -0700
Subject: [PATCH 06/17] Add cached client library instance sample

---
 functions/tips/index.js     | 26 ++++++++++++++++++++++++++
 functions/tips/package.json |  5 +++--
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/functions/tips/index.js b/functions/tips/index.js
index 7bb63bbd84..38575e5884 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -196,3 +196,29 @@ exports.retryCallback = (event, callback) => {
   }
 };
 // [END functions_tips_retry_callback]
+
+// [START functions_tips_gcp_apis]
+const Pubsub = require('@google-cloud/pubsub');
+const pubsub = Pubsub();
+
+/**
+ * HTTP Cloud Function that uses a cached client library instance to
+ * reduce the number of connections required per function invocation.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} req.body Cloud Function request context body.
+ * @param {String} req.body.topic The Cloud Pub/Sub topic to publish to.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.gcpApiCall = (req, res) => {
+  const topic = pubsub.topic(req.body.topic);
+
+  topic.publish('Test message', err => {
+    if (err) {
+      res.status(500).send(`Error publishing the message: ${err}`);
+    } else {
+      res.status(200).send('1 message published');
+    }
+  });
+};
+// [END functions_tips_gcp_apis]
diff --git a/functions/tips/package.json b/functions/tips/package.json
index a3cfe24660..5668e4a942 100644
--- a/functions/tips/package.json
+++ b/functions/tips/package.json
@@ -13,14 +13,15 @@
   },
   "scripts": {
     "lint": "repo-tools lint",
-    "pretest": "npm run lint",
+    "pretest": "npm run lint"
   },
   "dependencies": {
+    "@google-cloud/pubsub": "^0.18.0",
     "safe-buffer": "5.1.1"
   },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "2.2.5",
-    "ava": "0.25.0",
+    "ava": "0.25.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,

From 5f2d2c148421abf80b7999ee1708a7359dd3efd0 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Wed, 25 Apr 2018 16:32:49 -0700
Subject: [PATCH 07/17] Move existing + add new conceptual samples

---
 functions/concepts/index.js     | 96 +++++++++++++++++++++++++++++++++
 functions/concepts/package.json | 23 ++++++++
 2 files changed, 119 insertions(+)
 create mode 100644 functions/concepts/index.js
 create mode 100644 functions/concepts/package.json

diff --git a/functions/concepts/index.js b/functions/concepts/index.js
new file mode 100644
index 0000000000..28cfc4d411
--- /dev/null
+++ b/functions/concepts/index.js
@@ -0,0 +1,96 @@
+/**
+ * Copyright 2016, Google, Inc.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+/**
+ * HTTP Cloud Function that demonstrates
+ * how to catch errors of different types.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.errorTypes = (req, res) => {
+  // [START functions_concepts_error_object]
+  try {
+    // Throw an Error object (to simulate a GCP API failure)
+    throw new Error('Error object!');
+  } catch (err) {
+    // err is already an Error object
+    console.error(err);
+  }
+  // [END functions_concepts_error_object]
+
+  /* eslint-disable no-throw-literal */
+  // [START functions_concepts_error_unknown]
+  try {
+    // Throw an unknown error type
+    if (Date.now() % 2 === 0) {
+      throw 'Error string!';
+    } else {
+      throw new Error('Error object!');
+    }
+  } catch (err) {
+    // Determine the error type
+    if (err instanceof Error) {
+      console.error(err);
+    } else {
+      console.error(new Error(err));
+    }
+  }
+  // [END functions_concepts_error_unknown]
+  /* eslint-enable no-throw-literal */
+
+  res.end();
+};
+
+// [START functions_concepts_stateless]
+// Global variable, but only shared within function instance.
+let count = 0;
+
+/**
+ * HTTP Cloud Function that counts how many times
+ * it is executed within a specific instance.
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.executionCount = (req, res) => {
+  count++;
+
+  // Note: the total function invocation count across
+  // all instances may not be equal to this value!
+  res.send(`Instance execution count: ${count}`);
+};
+// [END functions_concepts_stateless]
+
+// [START functions_after_response]
+exports.afterResponse = (req, res) => {
+  res.end();
+
+  // This statement may not execute
+  console.log('Function complete!');
+};
+// [END functions_after_response]
+
+// [START functions_after_timeout]
+exports.afterTimeout = (req, res) => {
+  setTimeout(() => {
+    // May not execute if function's timeout is <2 minutes
+    console.log('Function running...');
+    res.end();
+  }, 120000); // 2 minute delay
+};
+// [END functions_after_timeout]
diff --git a/functions/concepts/package.json b/functions/concepts/package.json
new file mode 100644
index 0000000000..a424b413cc
--- /dev/null
+++ b/functions/concepts/package.json
@@ -0,0 +1,23 @@
+{
+  "name": "nodejs-docs-samples-functions-concepts",
+  "version": "0.0.1",
+  "private": true,
+  "license": "Apache-2.0",
+  "author": "Google Inc.",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
+  },
+  "engines": {
+    "node": ">=4.3.2"
+  },
+  "scripts": {
+    "lint": "repo-tools lint"
+  },
+  "dependencies": {},
+  "devDependencies": {
+    "@google-cloud/nodejs-repo-tools": "2.2.5",
+    "ava": "0.25.0",
+    "supertest": "^3.0.0"
+  }
+}

From 925ed9a1defaefa789513db4f279e5a02fecca8b Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Wed, 25 Apr 2018 17:06:09 -0700
Subject: [PATCH 08/17] Add conceptual samples, round 3

---
 functions/concepts/index.js     | 85 +++++++++++++++++++++++++++++++--
 functions/concepts/loadable.js  | 22 +++++++++
 functions/concepts/package.json |  4 +-
 3 files changed, 105 insertions(+), 6 deletions(-)
 create mode 100644 functions/concepts/loadable.js

diff --git a/functions/concepts/index.js b/functions/concepts/index.js
index 28cfc4d411..0792d252c1 100644
--- a/functions/concepts/index.js
+++ b/functions/concepts/index.js
@@ -1,5 +1,5 @@
 /**
- * Copyright 2016, Google, Inc.
+ * Copyright 2018, Google, Inc.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
@@ -76,16 +76,30 @@ exports.executionCount = (req, res) => {
 };
 // [END functions_concepts_stateless]
 
-// [START functions_after_response]
+// [START functions_concepts_after_response]
+/**
+ * HTTP Cloud Function that may not completely
+ * execute due to early HTTP response
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
 exports.afterResponse = (req, res) => {
   res.end();
 
   // This statement may not execute
   console.log('Function complete!');
 };
-// [END functions_after_response]
+// [END functions_concepts_after_response]
 
-// [START functions_after_timeout]
+// [START functions_concepts_after_timeout]
+/**
+ * HTTP Cloud Function that may not completely
+ * execute due to function execution timeout
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
 exports.afterTimeout = (req, res) => {
   setTimeout(() => {
     // May not execute if function's timeout is <2 minutes
@@ -93,4 +107,65 @@ exports.afterTimeout = (req, res) => {
     res.end();
   }, 120000); // 2 minute delay
 };
-// [END functions_after_timeout]
+// [END functions_concepts_after_timeout]
+
+// [START functions_concepts_filesystem]
+const fs = require('fs');
+
+/**
+ * HTTP Cloud Function that lists files in the function directory
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.listFiles = (req, res) => {
+  fs.readdir(__dirname, (err, files) => {
+    if (err) {
+      console.error(err);
+      res.sendStatus(500);
+    } else {
+      console.log('Files', files);
+      res.sendStatus(200);
+    }
+  });
+};
+// [END functions_concepts_filesystem]
+
+// [START functions_concepts_modules]
+const path = require('path');
+const loadedModule = require(path.join(__dirname, 'loadable.js'));
+
+/**
+ * HTTP Cloud Function that runs a function loaded from another Node.js file
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.runLoadedModule = (req, res) => {
+  console.log(`Loaded function from file ${loadedModule.getFileName()}`);
+  res.end();
+};
+// [END functions_concepts_modules]
+
+// [START functions_concepts_requests]
+const request = require('request');
+
+/**
+ * HTTP Cloud Function that makes an HTTP request
+ *
+ * @param {Object} req Cloud Function request context.
+ * @param {Object} res Cloud Function response context.
+ */
+exports.makeRequest = (req, res) => {
+  // The URL to send the request to
+  const url = 'https://example.com';
+
+  request(url, (err, response) => {
+    if (!err && response.statusCode === 200) {
+      res.sendStatus(200);
+    } else {
+      res.sendStatus(500);
+    }
+  });
+};
+// [END functions_concepts_requests]
diff --git a/functions/concepts/loadable.js b/functions/concepts/loadable.js
new file mode 100644
index 0000000000..822b444d20
--- /dev/null
+++ b/functions/concepts/loadable.js
@@ -0,0 +1,22 @@
+/**
+ * Copyright 2018, Google, Inc.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+// [START functions_sample_module]
+exports.getFileName = () => {
+  return __filename;
+};
+// [END functions_sample_module]
diff --git a/functions/concepts/package.json b/functions/concepts/package.json
index a424b413cc..b561e48927 100644
--- a/functions/concepts/package.json
+++ b/functions/concepts/package.json
@@ -14,7 +14,9 @@
   "scripts": {
     "lint": "repo-tools lint"
   },
-  "dependencies": {},
+  "dependencies": {
+    "request": "^2.85.0"
+  },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "2.2.5",
     "ava": "0.25.0",

From bae2b5b0684018617186e436e3c8e8afbc1baccb Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Thu, 26 Apr 2018 11:50:49 -0700
Subject: [PATCH 09/17] Address comments

---
 functions/helloworld/index.js | 43 +----------------------------------
 functions/http/index.js       | 13 ++++++-----
 functions/tips/index.js       | 11 +++++----
 3 files changed, 14 insertions(+), 53 deletions(-)

diff --git a/functions/helloworld/index.js b/functions/helloworld/index.js
index 8aeda8654c..32ceeb4263 100644
--- a/functions/helloworld/index.js
+++ b/functions/helloworld/index.js
@@ -1,5 +1,5 @@
 /**
- * Copyright 2016, Google, Inc.
+ * Copyright 2018, Google, Inc.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
@@ -170,44 +170,3 @@ exports.helloTemplate = (req, res) => {
   res.send(html).end();
 };
 // [END functions_helloworld_template]
-
-/**
- * HTTP Cloud Function that demonstrates
- * how to catch errors of different types.
- *
- * @param {Object} req Cloud Function request context.
- * @param {Object} res Cloud Function response context.
- */
-exports.helloErrorTypes = (req, res) => {
-  // [START functions_helloworld_error_object]
-  try {
-    // Throw an Error object (to simulate a GCP API failure)
-    throw new Error('Error object!');
-  } catch (err) {
-    // err is already an Error object
-    console.error(err);
-  }
-  // [END functions_helloworld_error_object]
-
-  /* eslint-disable no-throw-literal */
-  // [START functions_helloworld_error_unknown]
-  try {
-    // Throw an unknown error type
-    if (Date.now() % 2 === 0) {
-      throw 'Error string!';
-    } else {
-      throw new Error('Error object!');
-    }
-  } catch (err) {
-    // Determine the error type
-    if (err instanceof Error) {
-      console.error(err);
-    } else {
-      console.error(new Error(err));
-    }
-  }
-  // [END functions_helloworld_error_unknown]
-  /* eslint-enable no-throw-literal */
-
-  res.end();
-};
diff --git a/functions/http/index.js b/functions/http/index.js
index 2d806c6053..fab17b21a5 100644
--- a/functions/http/index.js
+++ b/functions/http/index.js
@@ -154,7 +154,8 @@ exports.uploadFile = (req, res) => {
 
     // This callback will be invoked for each file uploaded.
     busboy.on('file', (fieldname, file, filename) => {
-      // Note: os.tmpdir() - and any files in it - must fit in memory.
+      // Note: os.tmpdir() points to an in-memory file system on GCF
+      // Thus, any files in it must fit in the instance's memory.
       const filepath = path.join(tmpdir, filename);
       uploads[fieldname] = filepath;
       file.pipe(fs.createWriteStream(filepath));
@@ -173,7 +174,7 @@ exports.uploadFile = (req, res) => {
     req.pipe(busboy);
   } else {
     // Ignore non-POST requests
-    res.status(405).send();
+    res.status(405).end();
   }
 };
 // [END functions_http_form_data]
@@ -189,7 +190,7 @@ const storage = require('@google-cloud/storage')();
  * @param {Object} res Cloud Function response context.
  */
 exports.getSignedUrl = (req, res) => {
-  if(req.method === 'POST') {
+  if (req.method === 'POST') {
     // TODO(developer) check that the user is authorized to upload
 
     // Get a reference to the destination file in GCS
@@ -203,7 +204,7 @@ exports.getSignedUrl = (req, res) => {
       contentType: req.body.contentType
     };
 
-    file.getSignedUrl(config, function(err, url) {
+    file.getSignedUrl(config, function (err, url) {
       if (err) {
         console.error(err);
         res.status(500).end();
@@ -212,7 +213,7 @@ exports.getSignedUrl = (req, res) => {
       res.send(url);
     });
   } else {
-      res.status(405).end();
+    res.status(405).end();
   }
-}
+};
 // [END functions_http_signed_url]
diff --git a/functions/tips/index.js b/functions/tips/index.js
index 38575e5884..eaa1715beb 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -45,13 +45,15 @@ exports.scopeDemo = (req, res) => {
   // This computation runs every time this function is called
   const functionVar = lightComputation();
 
-  res.end(`Per instance: ${instanceVar}, per function: ${functionVar}`);
+  res.send(`Per instance: ${instanceVar}, per function: ${functionVar}`);
 };
 // [END functions_tips_scopes]
 
 // [START functions_tips_lazy_globals]
-// This value is always initialized, which happens at cold-start
+// Always initialized (at cold-start)
 const nonLazyGlobal = fileWideComputation();
+
+// Declared at cold-start, but only initialized if/when the function executes
 let lazyGlobal;
 
 /**
@@ -64,7 +66,7 @@ exports.lazyGlobals = (req, res) => {
   // This value is initialized only if (and when) the function is called
   lazyGlobal = lazyGlobal || functionSpecificComputation();
 
-  res.end(`Lazy global: ${lazyGlobal}, non-lazy global: ${nonLazyGlobal}`);
+  res.send(`Lazy global: ${lazyGlobal}, non-lazy global: ${nonLazyGlobal}`);
 };
 // [END functions_tips_lazy_globals]
 
@@ -73,9 +75,8 @@ exports.lazyGlobals = (req, res) => {
 const http = require('http');
 // [END functions_tips_ephemeral_agent]
 const agent = new http.Agent({keepAlive: true});
-// [END functions_tips_cached_connection]
+// [END functions_tips_cached_agent]
 
-// TODO(ace-n) make sure this import works as intended
 // [START functions_tips_ephemeral_agent]
 /**
  * HTTP Cloud Function that uses an ephemeral HTTP agent

From ce54daa3addd4ec9b794f60691bd2bedd7252323 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Thu, 26 Apr 2018 12:27:39 -0700
Subject: [PATCH 10/17] Address comments, round 2

---
 functions/tips/.gcloudignore      | 16 +++++++++
 functions/tips/index.js           | 16 ++++++---
 functions/tips/package.json       |  3 +-
 functions/tips/test/index.test.js | 55 +++++++++++++++++++++++++++++++
 4 files changed, 84 insertions(+), 6 deletions(-)
 create mode 100644 functions/tips/.gcloudignore
 create mode 100644 functions/tips/test/index.test.js

diff --git a/functions/tips/.gcloudignore b/functions/tips/.gcloudignore
new file mode 100644
index 0000000000..ccc4eb240e
--- /dev/null
+++ b/functions/tips/.gcloudignore
@@ -0,0 +1,16 @@
+# This file specifies files that are *not* uploaded to Google Cloud Platform
+# using gcloud. It follows the same syntax as .gitignore, with the addition of
+# "#!include" directives (which insert the entries of the given .gitignore-style
+# file at that point).
+#
+# For more information, run:
+#   $ gcloud topic gcloudignore
+#
+.gcloudignore
+# If you would like to upload your .git directory, .gitignore file or files
+# from your .gitignore file, remove the corresponding line
+# below:
+.git
+.gitignore
+
+node_modules
diff --git a/functions/tips/index.js b/functions/tips/index.js
index eaa1715beb..b2d4f7201c 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -1,5 +1,5 @@
 /**
- * Copyright 2016, Google, Inc.
+ * Copyright 2018, Google, Inc.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
@@ -78,6 +78,7 @@ const agent = new http.Agent({keepAlive: true});
 // [END functions_tips_cached_agent]
 
 // [START functions_tips_ephemeral_agent]
+
 /**
  * HTTP Cloud Function that uses an ephemeral HTTP agent
  *
@@ -155,6 +156,7 @@ exports.avoidInfiniteRetries = (event, callback) => {
 
   // Do what the function is supposed to do
   console.log(`Processing event ${event} with age ${eventAge} ms.`);
+  callback();
 };
 // [END functions_tips_infinite_retries]
 
@@ -164,9 +166,11 @@ exports.avoidInfiniteRetries = (event, callback) => {
  * how to toggle retries using a promise
  *
  * @param {object} event The Cloud Functions event.
+ * @param {object} event.data Data included with the event.
+ * @param {object} event.data.retry Whether or not to retry the function.
  */
 exports.retryPromise = (event) => {
-  const tryAgain = false;
+  const tryAgain = !!event.data.retry;
 
   if (tryAgain) {
     throw new Error(`Retrying...`);
@@ -182,17 +186,19 @@ exports.retryPromise = (event) => {
  * how to toggle retries using a callback
  *
  * @param {object} event The Cloud Functions event.
+ * @param {object} event.data Data included with the event.
+ * @param {object} event.data.retry Whether or not to retry the function.
  * @param {function} callback The callback function.
  */
 exports.retryCallback = (event, callback) => {
-  const tryAgain = false;
+  const tryAgain = !!event.data.retry;
   const err = new Error('Error!');
 
   if (tryAgain) {
-    console.error(`Retrying: ${err}`);
+    console.error('Retrying:', err);
     callback(err);
   } else {
-    console.error(`Not retrying: ${err}`);
+    console.error('Not retrying:', err);
     callback();
   }
 };
diff --git a/functions/tips/package.json b/functions/tips/package.json
index 5668e4a942..e29698ada7 100644
--- a/functions/tips/package.json
+++ b/functions/tips/package.json
@@ -21,7 +21,8 @@
   },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "2.2.5",
-    "ava": "0.25.0"
+    "ava": "0.25.0",
+    "sinon": "^4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/tips/test/index.test.js b/functions/tips/test/index.test.js
new file mode 100644
index 0000000000..4bca0df209
--- /dev/null
+++ b/functions/tips/test/index.test.js
@@ -0,0 +1,55 @@
+/**
+ * Copyright 2018, Google, Inc.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+const sinon = require(`sinon`);
+const test = require(`ava`);
+const tools = require(`@google-cloud/nodejs-repo-tools`);
+
+const sample = require(`../`);
+
+test.beforeEach(tools.stubConsole);
+test.afterEach.always(tools.restoreConsole);
+
+test(`should demonstrate retry behavior for a promise`, async (t) => {
+  // Retry by throwing an error
+  t.throws(() => {
+    sample.retryPromise({ data: {
+      retry: true }
+    });
+  }, 'Retrying...');
+
+  // Terminate by returning a rejected promise
+  await t.throws(
+    sample.retryPromise({ data: {} }),
+    'Not retrying...'
+  );
+});
+
+test(`should demonstrate retry behavior for a callback`, (t) => {
+  const cb = sinon.stub();
+  const err = new Error('Error!');
+
+  // Retry by passing an error to the callback
+  sample.retryCallback({ data: {
+    retry: true }
+  }, cb);
+  t.deepEqual(cb.firstCall.args, [err]);
+
+  // Terminate by passing nothing to the callback
+  sample.retryCallback({ data: {} }, cb);
+  t.deepEqual(cb.secondCall.args, []);
+});

From 5639b38cb56039357df94e3930bcc2ecaf3cc8b1 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Thu, 26 Apr 2018 13:10:58 -0700
Subject: [PATCH 11/17] Add unit test for concepts samples

---
 functions/concepts/index.js           |  6 +++-
 functions/concepts/package.json       |  5 +--
 functions/concepts/test/index.test.js | 46 +++++++++++++++++++++++++++
 3 files changed, 54 insertions(+), 3 deletions(-)
 create mode 100644 functions/concepts/test/index.test.js

diff --git a/functions/concepts/index.js b/functions/concepts/index.js
index 0792d252c1..6800aff3fb 100644
--- a/functions/concepts/index.js
+++ b/functions/concepts/index.js
@@ -20,6 +20,8 @@
  * how to catch errors of different types.
  *
  * @param {Object} req Cloud Function request context.
+ * @param {Object} req.body Cloud Function request context body.
+ * @param {String} req.body.topic The Cloud Pub/Sub topic to publish to.
  * @param {Object} res Cloud Function response context.
  */
 exports.errorTypes = (req, res) => {
@@ -33,11 +35,13 @@ exports.errorTypes = (req, res) => {
   }
   // [END functions_concepts_error_object]
 
+  const someCondition = !!req.body.throwAsString;
+
   /* eslint-disable no-throw-literal */
   // [START functions_concepts_error_unknown]
   try {
     // Throw an unknown error type
-    if (Date.now() % 2 === 0) {
+    if (someCondition) {
       throw 'Error string!';
     } else {
       throw new Error('Error object!');
diff --git a/functions/concepts/package.json b/functions/concepts/package.json
index b561e48927..298ba762f5 100644
--- a/functions/concepts/package.json
+++ b/functions/concepts/package.json
@@ -18,8 +18,9 @@
     "request": "^2.85.0"
   },
   "devDependencies": {
-    "@google-cloud/nodejs-repo-tools": "2.2.5",
-    "ava": "0.25.0",
+    "@google-cloud/nodejs-repo-tools": "^2.2.5",
+    "ava": "^0.25.0",
+    "sinon": "^4.5.0",
     "supertest": "^3.0.0"
   }
 }
diff --git a/functions/concepts/test/index.test.js b/functions/concepts/test/index.test.js
new file mode 100644
index 0000000000..2652c3e52d
--- /dev/null
+++ b/functions/concepts/test/index.test.js
@@ -0,0 +1,46 @@
+/**
+ * Copyright 2018, Google, Inc.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+const sinon = require(`sinon`);
+const test = require(`ava`);
+const tools = require(`@google-cloud/nodejs-repo-tools`);
+
+const sample = require(`../`);
+
+test.beforeEach(tools.stubConsole);
+test.afterEach.always(tools.restoreConsole);
+
+test(`should demonstrate error type behavior`, (t) => {
+  const objError = new Error('Error object!');
+  const strError = new Error('Error string!');
+
+  const req = { body:
+    { throwAsString: true }
+  };
+  const res = { end: sinon.stub() };
+
+  // Test throwing both objects and strings
+  sample.errorTypes(req, res);
+  t.deepEqual(console.error.getCall(0).args, [objError]);
+  t.deepEqual(console.error.getCall(1).args, [strError]);
+
+  // Test throwing objects only
+  req.body.throwAsString = false;
+  sample.errorTypes(req, res);
+  t.deepEqual(console.error.getCall(2).args, [objError]);
+  t.deepEqual(console.error.getCall(3).args, [objError]);
+})
\ No newline at end of file

From 09f9efeb73a82c68d67bc7555c829522b5767042 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Thu, 26 Apr 2018 13:22:54 -0700
Subject: [PATCH 12/17] Clarify comments

---
 functions/tips/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/functions/tips/index.js b/functions/tips/index.js
index b2d4f7201c..7616ebf844 100644
--- a/functions/tips/index.js
+++ b/functions/tips/index.js
@@ -35,7 +35,7 @@ const fileWideComputation = lightComputation;
 const instanceVar = heavyComputation();
 
 /**
- * Sample HTTP Cloud Function.
+ * HTTP Cloud Function that declares a variable.
  *
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
@@ -57,7 +57,7 @@ const nonLazyGlobal = fileWideComputation();
 let lazyGlobal;
 
 /**
- * Sample HTTP Cloud Function.
+ * HTTP Cloud Function that uses lazy-initialized globals
  *
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.

From ea3bb0d381cd4b0dd77807bf268caa04459c38c9 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Thu, 26 Apr 2018 13:59:59 -0700
Subject: [PATCH 13/17] Fix lint

---
 functions/concepts/test/index.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/functions/concepts/test/index.test.js b/functions/concepts/test/index.test.js
index 2652c3e52d..f0ffaf4129 100644
--- a/functions/concepts/test/index.test.js
+++ b/functions/concepts/test/index.test.js
@@ -43,4 +43,4 @@ test(`should demonstrate error type behavior`, (t) => {
   sample.errorTypes(req, res);
   t.deepEqual(console.error.getCall(2).args, [objError]);
   t.deepEqual(console.error.getCall(3).args, [objError]);
-})
\ No newline at end of file
+});

From fe260b22d684be544d1bfe8285dee09d4914355f Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Fri, 27 Apr 2018 11:37:40 -0700
Subject: [PATCH 14/17] Make comments consistent

---
 functions/http/index.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/functions/http/index.js b/functions/http/index.js
index fab17b21a5..13a92e9b13 100644
--- a/functions/http/index.js
+++ b/functions/http/index.js
@@ -173,7 +173,7 @@ exports.uploadFile = (req, res) => {
 
     req.pipe(busboy);
   } else {
-    // Ignore non-POST requests
+    // Return a "method not allowed" error
     res.status(405).end();
   }
 };
@@ -213,6 +213,7 @@ exports.getSignedUrl = (req, res) => {
       res.send(url);
     });
   } else {
+    // Return a "method not allowed" error
     res.status(405).end();
   }
 };

From edd196e2ff8b49673b316857d63a7824c06f8574 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Mon, 30 Apr 2018 13:33:35 -0700
Subject: [PATCH 15/17] Fix failing + add new tests

---
 circle.yml | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/circle.yml b/circle.yml
index e98ee2eea5..3737695447 100644
--- a/circle.yml
+++ b/circle.yml
@@ -35,10 +35,13 @@ dependencies:
     - yarn install
     - yarn run lint
     - samples test install -l=functions/background
+    - samples test install -l=functions/concepts
+    - samples test install -l=functions/datastore
+    - samples test install -l=functions/debug
     - samples test install -l=functions/errorreporting
     - samples test install -l=functions/gcs
-    - samples test install -l=functions/datastore
     - samples test install -l=functions/helloworld
+    - samples test install -l=functions/http
     - samples test install -l=functions/imagemagick
     - samples test install -l=functions/log
     - samples test install -l=functions/ocr/app
@@ -46,11 +49,14 @@ dependencies:
     - samples test install -l=functions/sendgrid
     - samples test install -l=functions/slack
     - samples test install -l=functions/spanner
+    - samples test install -l=functions/tips
     - samples test install -l=functions/uuid
   cache_directories:
     - ~/.cache/yarn
     - functions/background/node_modules
+    - functions/concepts/node_modules
     - functions/datastore/node_modules
+    - functions/debug/node_modules
     - functions/errorreporting/node_modules
     - functions/gcs/node_modules
     - functions/helloworld/node_modules
@@ -62,6 +68,7 @@ dependencies:
     - functions/sendgrid/node_modules
     - functions/slack/node_modules
     - functions/spanner/node_modules
+    - functions/tips/node_modules
     - functions/uuid/node_modules
 
 # Run your tests
@@ -70,6 +77,7 @@ test:
     - functions-emulator config set projectId $GCLOUD_PROJECT && functions-emulator start && cd functions/datastore && npm run system-test && functions-emulator stop
     - functions-emulator config set projectId $GCLOUD_PROJECT && functions-emulator start && cd functions/helloworld && npm run test && functions-emulator stop
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/background/test/**/*.test.js'
+    - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/concepts/test/**/*.test.js'
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/gcs/test/**/*.test.js'
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/http/test/**/*.test.js'
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/imagemagick/test/**/*.test.js'
@@ -79,6 +87,7 @@ test:
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/slack/test/**/*.test.js'
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/spanner/test/**/*.test.js'
     - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/uuid/test/**/*.test.js'
+    - samples test run --cmd nyc -- --cache ava --verbose -T 30s 'functions/tips/test/**/*.test.js'
   post:
     - nyc report --reporter=lcov > coverage.lcov && codecov || true
 deployment:

From b53bd1ce31193ed807c7f06d2ca21dfb414e09dc Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Mon, 30 Apr 2018 13:52:40 -0700
Subject: [PATCH 16/17] Don't run debug tests

---
 circle.yml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/circle.yml b/circle.yml
index 3737695447..624ed6bee5 100644
--- a/circle.yml
+++ b/circle.yml
@@ -37,7 +37,6 @@ dependencies:
     - samples test install -l=functions/background
     - samples test install -l=functions/concepts
     - samples test install -l=functions/datastore
-    - samples test install -l=functions/debug
     - samples test install -l=functions/errorreporting
     - samples test install -l=functions/gcs
     - samples test install -l=functions/helloworld
@@ -56,7 +55,6 @@ dependencies:
     - functions/background/node_modules
     - functions/concepts/node_modules
     - functions/datastore/node_modules
-    - functions/debug/node_modules
     - functions/errorreporting/node_modules
     - functions/gcs/node_modules
     - functions/helloworld/node_modules

From db5b186b56d1475d646646e5379502110a502f01 Mon Sep 17 00:00:00 2001
From: Ace Nassri <anassri@google.com>
Date: Mon, 30 Apr 2018 14:06:52 -0700
Subject: [PATCH 17/17] Increment Node version

---
 circle.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/circle.yml b/circle.yml
index 624ed6bee5..93790d7600 100644
--- a/circle.yml
+++ b/circle.yml
@@ -18,7 +18,7 @@
 
 machine:
   node:
-    version: 6.12.3
+    version: 6.14.1
 
 # Use for broader build-related configuration
 general: