# Receive direct events from Cloud Storage (gcloud CLI)
This quickstart shows you how to receive direct events from Cloud Storage
([without using Cloud Audit Logs](https://docs.cloud.google.com/eventarc/standard/docs/run/create-trigger-cloud-audit-logs-gcloud.md.txt))
in an *unauthenticated* Cloud Run service using
Eventarc.
> [!NOTE]
> **Note:** All Cloud Run services are deployed privately by default, which means that they can't be accessed without providing authentication credentials in the request. For projects with [domain restricted sharing organization policies](https://docs.cloud.google.com/resource-manager/docs/organization-policy/restricting-domains), use an authenticated Cloud Run target service rather than one that allows [public access](https://docs.cloud.google.com/run/docs/authenticating/public.md.txt).
You can configure the triggering of notifications in response
to various events inside a Cloud Storage bucket---object creation,
deletion, archiving, and metadata updates. For more information, see
[Create a trigger to route Cloud Storage events to Cloud Run](https://docs.cloud.google.com/eventarc/standard/docs/run/route-trigger-cloud-storage.md.txt).
In this quickstart, you:
1. Create a Cloud Storage bucket to be the event source.
2. Deploy an event receiver service to Cloud Run.
3. Create an Eventarc trigger.
4. Generate an event by uploading a file to the Cloud Storage bucket,
and view it in the Cloud Run logs.
## Before you begin
Security constraints defined by your organization might prevent you from completing the
following steps. For troubleshooting information, see
[Develop applications in a constrained Google Cloud environment](https://docs.cloud.google.com/resource-manager/docs/organization-policy/develop-apps-constrained-environment).
1. Enable the Cloud Run, Cloud Storage,
Eventarc, and Pub/Sub APIs.
```bash
gcloud services enable \
eventarc.googleapis.com \
pubsub.googleapis.com \
run.googleapis.com \
storage.googleapis.com
```
2. Update `gcloud` components:
```bash
gcloud components update
```
3. Sign in using your account:
```
gcloud auth login
```
4. Set the configuration variables used in this quickstart:
```
gcloud config set run/region us-central1
gcloud config set run/platform managed
gcloud config set eventarc/location us-central1
```
5. If you are the project creator, you are granted the
[basic Owner role](https://docs.cloud.google.com/iam/docs/roles-overview.md.txt#basic)
(`roles/owner`). By default, this Identity and Access Management (IAM) role
includes the permissions necessary for full access to most Google Cloud
resources and you can skip this step.
If you are not the project creator, required permissions must be granted on
the project to the appropriate *principal*. For example, a principal can be
a Google Account (for end users) or a service account (for applications and
compute workloads). For more information, see the
[Roles and permissions](https://docs.cloud.google.com/eventarc/docs/all-roles-permissions.md.txt) page
for your event destination.
#### Required permissions
To get the permissions that
you need to complete this tutorial,
ask your administrator to grant you the
following IAM roles on your project:
- [Cloud Run Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/run.md.txt#run.admin) (`roles/run.admin`)
- [Eventarc Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/eventarc.md.txt#eventarc.admin) (`roles/eventarc.admin`)
- [Logs View Accessor](https://docs.cloud.google.com/iam/docs/roles-permissions/logging.md.txt#logging.viewAccessor) (`roles/logging.viewAccessor`)
- [Project IAM Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/resourcemanager.md.txt#resourcemanager.projectIamAdmin) (`roles/resourcemanager.projectIamAdmin`)
- [Service Account Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/iam.md.txt#iam.serviceAccountAdmin) (`roles/iam.serviceAccountAdmin`)
- [Service Account User](https://docs.cloud.google.com/iam/docs/roles-permissions/iam.md.txt#iam.serviceAccountUser) (`roles/iam.serviceAccountUser`)
- [Service Usage Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/serviceusage.md.txt#serviceusage.serviceUsageAdmin) (`roles/serviceusage.serviceUsageAdmin`)
- [Storage Admin](https://docs.cloud.google.com/iam/docs/roles-permissions/storage.md.txt#storage.admin) (`roles/storage.admin`)
For more information about granting roles, see [Manage access to projects, folders, and organizations](https://docs.cloud.google.com/iam/docs/granting-changing-revoking-access.md.txt).
You might also be able to get
the required permissions through [custom
roles](https://docs.cloud.google.com/iam/docs/creating-custom-roles) or other [predefined
roles](https://docs.cloud.google.com/iam/docs/roles-overview#predefined).
6. Make note of the [Compute Engine
default service account](https://docs.cloud.google.com/iam/docs/service-account-types#default) as you will attach it to an Eventarc trigger to represent
the identity of the trigger for testing purposes. This service account is automatically created
after enabling or using a Google Cloud service that uses Compute Engine, and with the
following email format:
```bash
PROJECT_NUMBER-compute@developer.gserviceaccount.com
```
Replace `PROJECT_NUMBER` with your Google Cloud
project number. You can find your project number on the
[Welcome](https://console.cloud.google.com/welcome)
page of the Google Cloud console or by running the following command:
```bash
gcloud projects describe PROJECT_ID --format='value(projectNumber)'
```
For production environments, we strongly recommend
[creating a new service account](https://docs.cloud.google.com/iam/docs/service-accounts-create.md.txt)
and granting it one or more IAM roles that contain the
[minimum permissions required](https://docs.cloud.google.com/iam/docs/best-practices-service-accounts.md.txt#limit-service-account-privileges)
and follow the principle of [least privilege](https://docs.cloud.google.com/iam/docs/using-iam-securely.md.txt#least_privilege).
> [!NOTE]
> **Note:**
>
>
> The [`iam.automaticIamGrantsForDefaultServiceAccounts` organization policy constraint](https://docs.cloud.google.com/resource-manager/docs/organization-policy/restricting-service-accounts#disable_service_account_default_grants)
> prevents the Editor role from being automatically granted to default service accounts. If you
> created your organization after May 3, 2024, this constraint is enforced by
> default.
>
>
> We strongly recommend that you enforce this constraint to disable the automatic role grant. If you
> disable the automatic role grant, you must decide which roles to grant to the default service
> accounts, and then [grant these roles](https://docs.cloud.google.com/iam/docs/granting-changing-revoking-access.md.txt)
> yourself.
>
>
> If the default service account already has the Editor role, we recommend that you replace the
> Editor role with less permissive roles.To safely modify the service account's roles, use [Policy Simulator](https://docs.cloud.google.com/policy-intelligence/docs/simulate-iam-policies.md.txt) to see the impact of
> the change, and then [grant and revoke the
> appropriate roles](https://docs.cloud.google.com/iam/docs/granting-changing-revoking-access).
7. Grant the [Eventarc
Event Receiver role](https://docs.cloud.google.com/iam/docs/roles-permissions/eventarc#eventarc.eventReceiver) (`roles/eventarc.eventReceiver`) on the project to the Compute Engine default service account so that the Eventarc trigger can receive events from event providers.
```bash
gcloud projects add-iam-policy-binding PROJECT_ID \
--member=serviceAccount:PROJECT_NUMBER-compute@developer.gserviceaccount.com \
--role=roles/eventarc.eventReceiver
```
8. Before creating a trigger for direct events from Cloud Storage, grant the [Pub/Sub
Publisher role](https://docs.cloud.google.com/iam/docs/roles-permissions/pubsub#pubsub.publisher) (`roles/pubsub.publisher`) to the Cloud Storage service agent:
```bash
SERVICE_ACCOUNT="$(gcloud storage service-agent --project=PROJECT_ID)"
gcloud projects add-iam-policy-binding PROJECT_ID \
--member="serviceAccount:${SERVICE_ACCOUNT}" \
--role='roles/pubsub.publisher'
```
9. If you enabled the Cloud Pub/Sub service agent on or before April 8, 2021, to support authenticated Pub/Sub push requests, grant the [Service
Account Token Creator role](https://docs.cloud.google.com/iam/docs/roles-permissions/iam#iam.serviceAccountTokenCreator) (`roles/iam.serviceAccountTokenCreator`) to the service agent. Otherwise, this role is granted by default:
```bash
gcloud projects add-iam-policy-binding PROJECT_ID \
--member=serviceAccount:service-PROJECT_NUMBER@gcp-sa-pubsub.iam.gserviceaccount.com \
--role=roles/iam.serviceAccountTokenCreator
```
## Create a Cloud Storage bucket
Create a Cloud Storage bucket to use as the event source:
```bash
gcloud storage buckets create gs://PROJECT_ID-bucket/ --location=us-central1
```
> [!NOTE]
> **Note:** The Cloud Storage bucket must reside in the same Google Cloud project and [region or multi-region](https://docs.cloud.google.com/eventarc/docs/locations.md.txt) as the Eventarc trigger.
After the event source is created, you can deploy the event receiver service on
Cloud Run.
## Deploy the event receiver service to Cloud Run
Deploy a Cloud Run service that will receive and log events using
a prebuilt image, `us-docker.pkg.dev/cloudrun/container/hello`:
```bash
gcloud run deploy helloworld-events \
--image=us-docker.pkg.dev/cloudrun/container/hello \
--allow-unauthenticated
```
When the deployment succeeds, the command line displays the service URL.
Now that you have deployed a event receiver service called `helloworld-events`
to Cloud Run, you can set up your trigger.
## Create an Eventarc trigger
The Eventarc trigger sends events from the
Cloud Storage bucket to the `helloworld-events`
Cloud Run service.
1. Create a trigger that filters Cloud Storage events and that uses
the Compute Engine default service account.
```bash
gcloud eventarc triggers create storage-events-trigger \
--destination-run-service=helloworld-events \
--destination-run-region=us-central1 \
--event-filters="type=google.cloud.storage.object.v1.finalized" \
--event-filters="bucket=PROJECT_ID-bucket" \
--service-account=PROJECT_NUMBER-compute@developer.gserviceaccount.com
```
This creates a trigger called `storage-events-trigger`.
Note that when creating an Eventarc trigger for the first
time in a Google Cloud project, there might be a delay in provisioning
the Eventarc service agent. This issue can usually be resolved
by attempting to create the trigger again. For more information, see
[Permission denied errors](https://docs.cloud.google.com/eventarc/docs/troubleshooting.md.txt#trigger-error).
2. To confirm `storage-events-trigger` was successfully created, run:
```bash
gcloud eventarc triggers list --location=us-central1
```
The output is similar to the following:
NAME TYPE DESTINATION_RUN_SERVICE DESTINATION_RUN_PATH ACTIVE
storage-events-trigger google.cloud.storage.object.v1.finalized helloworld-events Yes
> [!NOTE]
> **Note:** Although your trigger is created immediately, it can take up to two minutes for triggers to be fully functional.
## Generate and view an event
1. To generate an event, upload a text file to Cloud Storage:
```
echo "Hello World" > random.txt
gcloud storage cp random.txt gs://PROJECT_ID-bucket/random.txt
```
The upload generates an event and the Cloud Run
service logs the event's message.
2. To view the log entry, filter the log entries, and return the output in JSON
format:
```
gcloud logging read 'jsonPayload.message: "Received event of type google.cloud.storage.object.v1.finalized."'
```
3. Look for a log entry similar to the following:
```
jsonPayload:
event:
...
eventType: google.cloud.storage.object.v1.finalized
message: |
Received event of type google.cloud.storage.object.v1.finalized. Event data: {
"kind": "storage#object",
"id": "PROJECT_ID-bucket/random.txt/1713970683868432",
"selfLink": "https://www.googleapis.com/storage/v1/b/PROJECT_ID-bucket/o/random.txt",
"name": "random.txt",
"bucket": "PROJECT_ID-bucket",
...
}
```
> [!NOTE]
> **Note:** If you don't see a log entry, wait a few minutes and retry the `gcloud logging read` command. The trigger can take up to two minutes after being created to start filtering events.
Congratulations! You have successfully deployed an event receiver service to
Cloud Run, created an Eventarc
trigger, generated an event from Cloud Storage, and viewed it in the
Cloud Run logs.
## Clean up
When you finish the tasks that are described in this document, you can avoid
continued billing by deleting the resources that you created.
You can:
1. [Delete the Cloud Storage bucket](https://docs.cloud.google.com/storage/docs/deleting-buckets.md.txt).
2. [Delete the Cloud Run service](https://docs.cloud.google.com/run/docs/managing/services.md.txt#delete).
3. [Delete the Eventarc trigger](https://docs.cloud.google.com/eventarc/docs/managing-triggers.md.txt#deleting_triggers).
Alternatively, you can delete your Google Cloud project to avoid incurring charges.
Deleting your Google Cloud project stops billing for all the resources used
within that project.
> [!CAUTION]
> **Caution** : Deleting a project has the following effects:
>
> - **Everything in the project is deleted.** If you used an existing project for the tasks in this document, when you delete it, you also delete any other work you've done in the project.
> - **Custom project IDs are lost.** When you created this project, you might have created a custom project ID that you want to use in the future. To preserve the URLs that use the project ID, such as an `appspot.com` URL, delete selected resources inside the project instead of deleting the whole project.
Delete a Google Cloud project:
```
gcloud projects delete PROJECT_ID
```
If you plan to explore multiple tutorials and quickstarts, reusing projects can
help you avoid exceeding project quota limits.
## What's next
- [Build containers for Cloud Run](https://docs.cloud.google.com/run/docs/building/containers.md.txt)
- [Execute a Cloud Run job in a workflow using an Eventarc trigger](https://docs.cloud.google.com/workflows/docs/tutorials/execute-cloud-run-jobs.md.txt)
- [Develop Cloud Run services](https://docs.cloud.google.com/run/docs/developing.md.txt)