Configure environment variables

When you set environment variables, they are injected into the container and are accessible to your code. Environment variables are set as key/value pairs.

Reserved names

The environment variables defined in the container runtime contract are reserved and cannot be set. In particular, the PORT environment variable is injected inside your container by Cloud Run. You should not set it yourself.

Maximum number of environment variables

Note that you can set a maximum of 1000 environment variables per container for each Cloud Run service.

Required roles

To get the permissions that you need to configure and deploy Cloud Run services, ask your administrator to grant you the following IAM roles on service:

Cloud Run Developer (roles/run.developer) - the Cloud Run service
Service Account User (roles/iam.serviceAccountUser) - the service identity

For a list of IAM roles and permissions that are associated with Cloud Run, see Cloud Run IAM roles and Cloud Run IAM permissions. If your Cloud Run service interfaces with Google Cloud APIs, such as Cloud Client Libraries, see the service identity configuration guide. For more information about granting roles, see deployment permissions and manage access.

Set environment variables

Any configuration change leads to the creation of a new revision. Subsequent revisions will also automatically get this configuration setting unless you make explicit updates to change it.

You can set environment variables using the Google Cloud console, the gcloud command line, or a YAML file when you create a new service or deploy a new revision:

Console

In the Google Cloud console, go to Cloud Run:

Go to Cloud Run
Click Deploy container and select Service to configure a new service. If you are configuring an existing service, click the service, then click Edit and deploy new revision.
If you are configuring a new service, fill out the initial service settings page, then click Container(s), volumes, networking, security to expand the service configuration page.
Click the Container tab.
- Do the following:
  - If you are adding a variable, click Add Variable, and specify the name you want for the variable and its value in the Name and Value text boxes.
  - If you are changing a value for a variable, replace the current value in the Value text box with the one you want.
  - If you are removing one or more environment variables, hover your cursor to the left of the Value textbox of the variable you are removing to display the Trash icon, and click it.
Click Create or Deploy.

gcloud

To set, update, or remove environment variables of an existing service, use the gcloud run services update command. To set, update, or remove environment variables of an existing multi-region service, use the gcloud beta run multi-region-services update command.

You can use any of the following flags, as needed:

You can specify environment variables while deploying a service, or update them after the service is created:

gcloud run deploy [SERVICE] --image IMAGE_URL --update-env-vars KEY1=VALUE1,KEY2=VALUE2

gcloud run services update SERVICE --update-env-vars KEY1=VALUE1,KEY2=VALUE2

Replace SERVICE with the name of your service.
Replace KEY1=VALUE1,KEY2=VALUE2, with the comma separated list of desired variable names and their values.
Replace IMAGE_URL with a reference to the container image, for example, us-docker.pkg.dev/cloudrun/container/hello:latest. If you use Artifact Registry, the repository REPO_NAME must already be created. The URL has the shape LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/PATH:TAG .

YAML

If you are creating a new service, skip this step. If you are updating an existing service, download its YAML configuration:
```
gcloud run services describe SERVICE --format export > service.yaml
```
Update the name and value attributes under the env attribute under containers::
```
apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: SERVICE
spec:
  template:
    metadata:
      name: REVISION
    spec:
      containers:
      - image: IMAGE
        env:
        - name: KEY-1
          value: VALUE-1
        - name: KEY-N
          value: VALUE-N
```
Replace
- SERVICE with the name of your Cloud Run service
- IMAGE_URL with a reference to the container image, for example, us-docker.pkg.dev/cloudrun/container/hello:latest. If you use Artifact Registry, the repository REPO_NAME must already be created. The URL has the shape LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/PATH:TAG
- KEY-1, VALUE-1 with the environment variable and value. Optionally add more variables and values as desired.
- REVISION with a new revision name or delete it (if present). If you supply a new revision name, it must meet the following criteria:
  - Starts with SERVICE-
  - Contains only lowercase letters, numbers and -
  - Does not end with a -
  - Does not exceed 63 characters
Create or update the service using the following command:
```
gcloud run services replace service.yaml
```

Terraform

To learn how to apply or remove a Terraform configuration, see Basic Terraform commands.

The following google_cloud_run_v2_service resource specifies sets the foo environment variable to bar, and the baz environment variable to quux. Update the environment variables as desired for your specific needs:

resource "google_cloud_run_v2_service" "default" {
  name     = "cloudrun-service-env-var"
  location = "us-central1"

  deletion_protection = false # set to "true" in production

  template {
    containers {
      image = "us-docker.pkg.dev/cloudrun/container/hello"

      # Environment variables
      env {
        name  = "foo"
        value = "bar"
      }
      env {
        name  = "baz"
        value = "quux"
      }
    }
  }
}

Set many environment variables

If you have too many environment variables that cannot be easily listed in KEY1=VALUE1,KEY2=VALUE2 format, you can alternatively repeat the flags listed above multiple times:

   [...]
   --set-env-vars "KEY1=VALUE1" \
   --set-env-vars "KEY2=VALUE2" \
   --set-env-vars "KEY3=VALUE3"

Escape comma characters

Because the comma character , is used to split environment variables, if your environment variable contains comma characters as values, you need to escape those delimiters by specifying a different delimiter character, for example, @:

--set-env-vars "^@^KEY1=value1,value2,value3@KEY2=..."

Set default environment variables in the container

You can use the ENV statement in a Dockerfile to set default values for environment variables:

ENV KEY1=VALUE1,KEY2=VALUE2

Order of precedence: container vs service or job variables

If you set a default environment variable in the container and also set an environment variable with the same name on the Cloud Run service or job, the value set on the service takes precedence.

View environment variables settings

To view the current environment variables settings for your Cloud Run service:

Console

In the Google Cloud console, go to Cloud Run:

Go to Cloud Run
Click the service you are interested in to open the Service details page.
Click the Revisions tab.
In the details panel at the right, the environment variables setting is listed under the Container tab.

gcloud

Use the following command:
```
gcloud run services describe SERVICE
```
Locate the environment variables setting in the returned configuration.

Sample code

For code sample that show how to access environment variables in your code, refer to Handling sensitive configuration with Secret Manager in the End user authentication tutorial.

What's next

You can use environment variables to set Buildpack configuration. For language-specific details, see the Buildpacks documentation for: