This is the Archived version of the documentation. The free trial period ended on Sept. 30, 2021.

See the GA version documentation for details about installing Cloud Run for Anthos as an Anthos fleet component with Anthos Service Mesh.

Setting environment variables

Learn how to create and use environment variables in Cloud Run for Anthos.

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. For example, suppose you are running a service that enables additional logging when it reads LOGGING_VERBOSE: true in the environment. In this scenario, you set the environment variable key/value pair as LOGGING_VERBOSE=true. The exact commands or UI are shown in the following sections.

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 for Anthos. You should not set it yourself.

Setting environment variables on a service

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 console, the Google Cloud CLI, or a YAML file when you deploy a new service or update an existing service and deploy a revision:

Console

  1. Go to Cloud Run for Anthos in the console:

    Go to Cloud Run for Anthos

  2. Click Create Service if you are configuring a new service you are deploying to. If you are configuring an existing service, click on the service, then click Edit & Deploy New Revision.

  3. Under Advanced settings, click Variables and Secrets.

    image

  4. 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.

  5. Click Next to continue to the next section.

  6. In the Configure how this service is triggered section, select which connectivity you would like to use to invoke the service.

  7. Click Create to deploy the image to Cloud Run for Anthos and wait for the deployment to finish.

Command line

You can use the Google Cloud CLI to set environment variables for new services or to update existing services:

  • For existing services, update environment variables by running the gcloud run services update command with one of the following parameters:

    Example:

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

    Replace:

    • SERVICE with the name of your service.
    • KEY1=VALUE1,KEY2=VALUE2 with a comma separated list of name and value pairs for each environment variable. Specify the environment variable name for each KEY and the value of that environment variable for VALUE. How to specify multiple parameters.
    • Command parameter options

      • To specify an environment variable that contains a comma (,), you must escape each KEY=VALUE with a different delimiter. For example, if you use @:
        --set-env-vars "^@^KEY1=value,with,commas@KEY2=anothervalue@KEY3..."
        
      • To specify several sets of key-value pairs, you can specify multiple parameters for readability. Example:
        [...]
        --set-env-vars "KEY=VALUE1" \
        --set-env-vars "KEY=VALUE2" \
        --set-env-vars "KEY=VALUE3"
        
  • For new services, set environment variables by running the gcloud run deploy command with the --set-env-vars parameter:

    gcloud run deploy SERVICE --image=IMAGE_URL --set-env-vars KEY1=VALUE1,KEY2=VALUE2
    

    Replace:

    • IMAGE_URL with a reference to the container image, for example, gcr.io/myproject/my-image:latest.
    • SERVICE with the name of your service.
    • KEY1=VALUE1,KEY2=VALUE2 with a comma separated list of name and value pairs for each environment variable. Specify the environment variable name for each KEY and the value of that environment variable for VALUE. How to specify multiple parameters.
    • Command parameter options

      • To specify an environment variable that contains a comma (,), you must escape each KEY=VALUE with a different delimiter. For example, if you use @:
        --set-env-vars "^@^KEY1=value,with,commas@KEY2=anothervalue@KEY3..."
        
      • To specify several sets of key-value pairs, you can specify multiple parameters for readability. Example:
        [...]
        --set-env-vars "KEY=VALUE1" \
        --set-env-vars "KEY=VALUE2" \
        --set-env-vars "KEY=VALUE3"
        

YAML

You can download the configuration of an existing service into a YAML file with the gcloud run services describe command by using the --format=export flag. You can then modify that YAML file and deploy those changes with the gcloud beta run services replace command. You must ensure that you modify only the specified attributes.

  1. Download the configuration of your service into a file named service.yaml on local workspace:

    gcloud run services describe SERVICE --format export > service.yaml

    Replace SERVICE with the name of your Cloud Run for Anthos service.

  2. In your local file, update the name and value attributes under the env attribute under containers::

    apiVersion: serving.knative.dev/v1
    kind: Service
    metadata:
      name: SERVICE
    spec:
      template:
        spec:
          containers:
          - env:
            - name: KEY-1
              value: VALUE-1
            - name: KEY-N
              value: VALUE-N

    Replace

    • SERVICE with the name of your Cloud Run for Anthos service
    • KEY-1, VALUE-1 with the environment variable and value. Optionally add more variables and values as desired.
  3. Replace the service with its new configuration using the following command:

    gcloud beta run services replace service.yaml

Setting 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 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 for Anthos service, the value set on the service takes precedence.

To use Kubernetes service links, you must manually enable support. Due to the performance issues seen in namespaces with thousands of services and revisions, Kubernetes service links were disabled by default starting in January 2021.

To enable Kubernetes service links, run the following command to set data.enable-service-links to true in your knative-serving/config-defaults ConfigMap:

kubectl patch cm -n knative-serving config-defaults -p '{"data":{"enable-service-links":"true"}}