Google ACE Practice Question: Arrange the steps to set up a Cloud Function…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  Create the Cloud Storage bucket → Write the Cloud Function code → Deploy the Cloud Function with bucket trigger → Upload a file to the bucket to test the trigger

  Why this is correct

  Creating the Cloud Storage bucket before deploying the Cloud Function ensures the bucket resource exists for the trigger to reference; if the bucket is missing, deployment fails with a resource-not-found error. Writing the function code before deployment is required because gcloud functions deploy packages and uploads the source to build the function. Deploying with the bucket trigger attaches an event listener (e.g., google.cloud.storage.object.v1.finalized) to the bucket. Finally, uploading a test file generates an event that invokes the function, confirming the trigger is configured correctly.

• ✗

  Write the Cloud Function code → Deploy the Cloud Function with bucket trigger → Create the Cloud Storage bucket → Upload a file to the bucket to test the trigger

  Why it's wrong here

  This order fails because deploying the Cloud Function with a bucket trigger before creating the bucket causes the deployment to fail validation, as the specified bucket resource does not exist at deploy time. Even though the bucket is created later, the deployment already errored out, so you never reach the testing step. In Cloud Functions (2nd gen), the Eventarc trigger validates the underlying bucket resource during deployment, so the bucket must pre-exist. Writing code first is correct, but it must be followed by bucket creation before deployment, not after.

• ✗

  Create the Cloud Storage bucket → Deploy the Cloud Function with bucket trigger → Write the Cloud Function code → Upload a file to the bucket to test the trigger

  Why it's wrong here

  This order is invalid because you cannot deploy a Cloud Function without having written its code first—the deployment process requires a source directory or archive to build and attach to the function. Creating the bucket first is fine, but deploying before the code exists leaves the deployment with nothing to upload, causing an error like 'Function source code not found.' The code must be written and staged before running the deploy command. Only after deployment can a test upload be used to verify the trigger fires.

• ✗

  Deploy the Cloud Function with bucket trigger → Write the Cloud Function code → Create the Cloud Storage bucket → Upload a file to the bucket to test the trigger

  Why it's wrong here

  This order violates multiple prerequisites: deploying a Cloud Function requires both the source code and the trigger resource (the bucket) to exist at the time of the deploy command. Without code, there is nothing to deploy; without the bucket, the trigger cannot be validated, so the deployment fails immediately. Furthermore, writing code and creating the bucket after deployment cannot retroactively fix the failed deployment. A correct sequence must first create the bucket, then write code, then deploy, and only then test with a file upload.

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