GSP080

Overview

A cloud function is a piece of code that runs in response to an event, such as an HTTP request, a message from a messaging service, or a file upload. Cloud events are things that happen in your cloud environment. These might be things like changes to data in a database, files added to a storage system, or a new virtual machine instance being created.

Since cloud functions are event-driven, they only run when something happens. This makes them a good choice for tasks that need to be done quickly or that don't need to be running all the time.

For example, you can use a cloud function to:

• automatically generate thumbnails for images that are uploaded to Cloud Storage.
• send a notification to a user's phone when a new message is received in Cloud Pub/Sub.
• process data from a Cloud Firestore database and generate a report.

You can write your code in any language that supports Node.js, and you can deploy your code to the cloud with a few clicks. Once your cloud function is deployed, it will automatically start running in response to events.

This hands-on lab shows you how to create, deploy, and test a cloud function using the Google Cloud console.

This hands-on lab shows you how to create, deploy, and test a cloud function using the Google Cloud Shell command line.

What you'll do

• Create a cloud function
• Deploy and test the cloud function
• View logs

Setup

Before you click the Start Lab button

Read these instructions. Labs are timed and you cannot pause them. The timer, which starts when you click Start Lab, shows how long Google Cloud resources will be made available to you.

This hands-on lab lets you do the lab activities yourself in a real cloud environment, not in a simulation or demo environment. It does so by giving you new, temporary credentials that you use to sign in and access Google Cloud for the duration of the lab.

To complete this lab, you need:

• Access to a standard internet browser (Chrome browser recommended).

Note: Use an Incognito or private browser window to run this lab. This prevents any conflicts between your personal account and the Student account, which may cause extra charges incurred to your personal account.

• Time to complete the lab---remember, once you start, you cannot pause a lab.

Note: If you already have your own personal Google Cloud account or project, do not use it for this lab to avoid extra charges to your account.

How to start your lab and sign in to the Google Cloud console

1. Click the Start Lab button. If you need to pay for the lab, a pop-up opens for you to select your payment method. On the left is the Lab Details panel with the following:

   • The Open Google Cloud console button
   • Time remaining
   • The temporary credentials that you must use for this lab
   • Other information, if needed, to step through this lab

2. Click Open Google Cloud console (or right-click and select Open Link in Incognito Window if you are running the Chrome browser).

   The lab spins up resources, and then opens another tab that shows the Sign in page.

   Tip: Arrange the tabs in separate windows, side-by-side.

   Note: If you see the Choose an account dialog, click Use Another Account.

3. If necessary, copy the Username below and paste it into the Sign in dialog.

   {{{user_0.username | "Username"}}}

   You can also find the Username in the Lab Details panel.

4. Click Next.

5. Copy the Password below and paste it into the Welcome dialog.

   {{{user_0.password | "Password"}}}

   You can also find the Password in the Lab Details panel.

6. Click Next.

   Important: You must use the credentials the lab provides you. Do not use your Google Cloud account credentials. Note: Using your own Google Cloud account for this lab may incur extra charges.

7. Click through the subsequent pages:

   • Accept the terms and conditions.
   • Do not add recovery options or two-factor authentication (because this is a temporary account).
   • Do not sign up for free trials.

After a few moments, the Google Cloud console opens in this tab.

Note: To view a menu with a list of Google Cloud products and services, click the Navigation menu at the top-left.

Activate Cloud Shell

Cloud Shell is a virtual machine that is loaded with development tools. It offers a persistent 5GB home directory and runs on the Google Cloud. Cloud Shell provides command-line access to your Google Cloud resources.

1. Click Activate Cloud Shell at the top of the Google Cloud console.

When you are connected, you are already authenticated, and the project is set to your Project_ID, . The output contains a line that declares the Project_ID for this session:

Your Cloud Platform project in this session is set to {{{project_0.project_id | "PROJECT_ID"}}}

gcloud is the command-line tool for Google Cloud. It comes pre-installed on Cloud Shell and supports tab-completion.

2. (Optional) You can list the active account name with this command:

gcloud auth list

3. Click Authorize.

Output:

ACTIVE: * ACCOUNT: {{{user_0.username | "ACCOUNT"}}} To set the active account, run: $ gcloud config set account `ACCOUNT`

4. (Optional) You can list the project ID with this command:

gcloud config list project

Output:

[core] project = {{{project_0.project_id | "PROJECT_ID"}}} Note: For full documentation of gcloud, in Google Cloud, refer to the gcloud CLI overview guide.

Task 1. Create a function

First, you're going to create a simple function named helloWorld. This function writes a message to the Cloud Functions logs. It is triggered by cloud function events and accepts a callback function used to signal completion of the function.

For this lab the cloud function event is a cloud pub/sub topic event. A pub/sub is a messaging service where the senders of messages are decoupled from the receivers of messages. When a message is sent or posted, a subscription is required for a receiver to be alerted and receive the message. To learn more about pub/subs, in Cloud Pub/Sub Guides, see Google Cloud Pub/Sub: A Google-Scale Messaging Service.

To learn more about the event parameter and the callback parameter, in Cloud Functions Documentation, see Background Functions.

To create a cloud function:

1. In Cloud Shell, run the following command to set the default region:

   gcloud config set run/region {{{project_0.default_region |REGION}}}

2. Create a directory for the function code:

   mkdir gcf_hello_world && cd $_

3. Create and open index.js to edit:

   nano index.js

4. Copy the following into the index.js file:

   const functions = require('@google-cloud/functions-framework'); // Register a CloudEvent callback with the Functions Framework that will // be executed when the Pub/Sub trigger topic receives a message. functions.cloudEvent('helloPubSub', cloudEvent => { // The Pub/Sub message is passed as the CloudEvent's data payload. const base64name = cloudEvent.data.message.data; const name = base64name ? Buffer.from(base64name, 'base64').toString() : 'World'; console.log(`Hello, ${name}!`); });

5. Exit nano (Ctrl+x) and save (Y) the file.

6. Create and open package.json to edit:

7. Copy the following into the package.json file:

   { "name": "gcf_hello_world", "version": "1.0.0", "main": "index.js", "scripts": { "start": "node index.js", "test": "echo \"Error: no test specified\" && exit 1" }, "dependencies": { "@google-cloud/functions-framework": "^3.0.0" } }

8. Exit nano (Ctrl+x) and save (Y) the file.

9. Install the package dependencies

   npm install

   Expected Output:

   added 140 packages, and audited 141 packages in 9s 27 packages are looking for funding run `npm fund` for details found 0 vulnerabilities

Task 2. Deploy your function

For this lab, you'll set the --trigger-topic as cf_demo.

Note:
Cloud Functions are event driven, meaning a trigger type must be specified. When deploying a new function, `--trigger-topic`, `--trigger-bucket`, or `--trigger-http` are common trigger events. When deploying an update to an existing function, the function keeps the existing trigger unless otherwise specified.

1. Deploy the helloPubSub function to a pub/sub topic named cf-demo

   gcloud functions deploy nodejs-pubsub-function \ --gen2 \ --runtime=nodejs20 \ --region={{{ project_0.default_region | REGION }}} \ --source=. \ --entry-point=helloPubSub \ --trigger-topic cf-demo \ --stage-bucket {{{ project_0.project_id | PROJECT_ID }}}-bucket \ --service-account cloudfunctionsa@{{{ project_0.project_id | PROJECT_ID }}}.iam.gserviceaccount.com \ --allow-unauthenticated Note:
   If you get a service account serviceAccountTokenCreator notification select "n".

2. Verify the status of the function:

   gcloud functions describe nodejs-pubsub-function \ --region={{{ project_0.default_region | REGION }}}

   An ACTIVE status indicates that the function has been deployed.

   Expected Output:

   BuildConfig: automaticUpdatePolicy: {} build: projects/630521560493/locations/{{{ project_0.default_region | REGION }}}/builds/7ff9d415-50d9-4557-9bcd-5afad42a6390 dockerRegistry: ARTIFACT_REGISTRY dockerRepository: projects/{{{ project_0.project_id | PROJECT_ID }}}/locations/{{{ project_0.default_region | REGION }}}/repositories/gcf-artifacts entryPoint: helloPubSub ... State: ACTIVE ... UpdateTime: '2024-08-05T13:51:05.317298824Z' Url: https://{{{ project_0.default_region | REGION }}}-{{{ project_0.project_id | PROJECT_ID }}}.cloudfunctions.net/nodejs-pubsub-function

Every message published in the topic triggers function execution, the message contents are passed as input data.

Test Completed Task

Click Check my progress to verify your performed task. If you have completed the task successfully you will receive an assessment score.

Deploy the function.

Task 3. Test the function

After you deploy the function and know that it's active, test that the function writes a message to the cloud log after detecting an event.

1. Invoke the PubSub with some data.

   gcloud pubsub topics publish cf-demo --message="Cloud Function Gen2"

   Example output:

   messageIds: - '11927162971409664'

View logs to confirm that there are log messages with that execution ID.

Task 4. View logs

1. Check the logs to see your messages in the log history:

   gcloud functions logs read nodejs-pubsub-function \ --region={{{ project_0.default_region | REGION }}} Note:
   The logs can take around 10 mins to appear. Also, the alternative way to view the logs is, go to Logging > Logs Explorer.

   The cloud function will output information similar to below:

   LEVEL: NAME: nodejs-pubsub-function EXECUTION_ID: h4v6akxf4sxt TIME_UTC: 2024-08-05 15:15:25.723 LOG: Hello, Cloud Function Gen2! LEVEL: I NAME: nodejs-pubsub-function EXECUTION_ID: TIME_UTC: 2024-08-05 15:15:25.711 LOG: LEVEL: NAME: nodejs-pubsub-function EXECUTION_ID: h4oxfjn7zlyu TIME_UTC: 2024-08-05 15:10:34.303 LOG: Hello, Friend! LEVEL: I NAME: nodejs-pubsub-function EXECUTION_ID: TIME_UTC: 2024-08-05 15:10:34.291 LOG: LEVEL: NAME: nodejs-pubsub-function EXECUTION_ID: h4fjhyfxua3k TIME_UTC: 2024-08-05 15:03:16.342 LOG: Hello, "SGVsbG8gZnJvbSB0aGUgY29tbWFuZCBsaW5l"!

Your application is deployed, tested, and you can view the logs.

Task 5. Test your understanding

1. Below are multiple-choice questions to reinforce your understanding of this lab's concepts. Answer them to the best of your abilities.

Congratulations!

You used the Google Cloud console to create, deploy, and test a cloud function using the command line.

Take your next lab

This lab is part of a series of labs called Qwik Starts. These labs are designed to give you a little taste of the many features available with Google Cloud. Search for "Qwik Starts" in the lab catalog to find the next lab you'd like to take!

Next steps / Learn more

• Now that you used the command line to start a Cloud Function, try the Cloud Functions: Qwik Start - Console lab to start a Cloud Function using the Cloud Console.
• For more information on creating triggers and associating them with your functions, see the Events and Triggers section of the Cloud Functions Guides.

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Manual Last Updated Aug 05, 2024

Lab Last Tested Aug 05, 2024

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