How to Deploy a Cloud Function on Google Cloud Platform

To deploy a cloud function on Google Cloud Platform, use the gcloud functions deploy command with your function name, runtime, trigger, and source code location. This command packages your code and sets up the function to run in the cloud.

Syntax

The basic command to deploy a Google Cloud Function is:

• gcloud functions deploy FUNCTION_NAME: Names your function.
• --runtime RUNTIME: Specifies the language runtime (like nodejs18, python39).
• --trigger-http: Sets the function to run on HTTP requests.
• --entry-point ENTRY_POINT: (Optional) The function name in your code to run.
• --source SOURCE_DIR: (Optional) Path to your function code folder.

bash

gcloud functions deploy FUNCTION_NAME --runtime RUNTIME --trigger-http --entry-point ENTRY_POINT --source SOURCE_DIR

Example

This example deploys a simple HTTP function named helloWorld written in Node.js 18. The function responds with 'Hello, World!' when called.

javascript

exports.helloWorld = (req, res) => {
  res.send('Hello, World!');
};

Example Deployment Command

Run this command in your terminal inside the folder containing the index.js file with the function code:

bash

gcloud functions deploy helloWorld --runtime nodejs18 --trigger-http --allow-unauthenticated

Output

Deploying function (may take a while)...
Deployments successful

availableMemoryMb: 256
entryPoint: helloWorld
httpsTrigger:
  url: https://REGION-PROJECT_ID.cloudfunctions.net/helloWorld
runtime: nodejs18
serviceAccountEmail: [e-mail]
status: ACTIVE
timeout: 60s
versionId: 1

Common Pitfalls

• Forgetting to specify --trigger-http when you want an HTTP function causes deployment errors.
• Not setting --allow-unauthenticated means your function requires authentication and may not respond publicly.
• Using the wrong runtime version causes deployment failure; check supported runtimes with gcloud functions runtimes list.
• Not running the command in the correct source folder or missing --source leads to missing code errors.

bash

Wrong:
gcloud functions deploy myFunc --runtime python39

Right:
gcloud functions deploy myFunc --runtime python39 --trigger-http --allow-unauthenticated

Quick Reference

Option	Description
FUNCTION_NAME	Name of your cloud function
--runtime	Language runtime (e.g., nodejs18, python39)
--trigger-http	Trigger function via HTTP requests
--entry-point	Function name in your code (default is 'function')
--source	Path to your function code folder
--allow-unauthenticated	Allow public access without login

Key Takeaways

Use the gcloud CLI with 'gcloud functions deploy' to deploy your cloud function.

Specify the runtime and trigger type clearly to avoid deployment errors.

Include '--allow-unauthenticated' for public HTTP functions.

Keep your function code in the right folder or specify it with '--source'.

Check supported runtimes with 'gcloud functions runtimes list' before deploying.