Access the Apache Airflow web user interface

Cloud Composer 1 | Cloud Composer 2

Apache Airflow includes a web user interface (UI) that you can use to manage workflows (DAGs), manage the Airflow environment, and perform administrative actions. For example, you can use the web interface to review the progress of a DAG, set up a new data connection, or review logs from previous DAG runs.

Airflow web server

Each Cloud Composer environment has a web server that runs the Airflow web interface. The web server is a part of Cloud Composer environment architecture.

Before you begin

• You must have a role that can view Cloud Composer environments. For more information, see Access control.

• During the environment creation, Cloud Composer configures the URL for the web server that runs the Airflow web interface. The URL is non-customizable.

• Cloud Composer 2 supports the Airflow UI Access Control (Airflow Role-Based Access Control) feature for the Airflow web interface.

• If the API Controls > Unconfigured third-party apps > Don't allow users to access any third-party apps option is enabled in Google Workspace and the Apache Airflow in Cloud Composer app is not explicitly allowed, then users are not able to access the Airflow UI unless they explicitly allow the application. To allow access, perform steps provided in Allow access to Airflow UI in Google Workspace.

Accessing the Airflow web interface

The Airflow web server runs as a workload in your environment's cluster. The web server is deployed to the composer.googleusercontent.com domain and provides access to the Airflow web interface.

Cloud Composer 2 provides access to the interface based on user identities and IAM policy bindings defined for users. Compared to Cloud Composer 1, Cloud Composer 2 uses a different mechanism that does not rely on Identity-Aware Proxy.

Accessing the web interface from the Google Cloud console

To access the Airflow web interface from the Google Cloud console:

1. In the Google Cloud console, go to the Environments page.

   Go to Environments

2. In the Airflow webserver column, follow the Airflow link for your environment.

Limiting access to the Airflow web server

Composer environments let you limit access to the Airflow web server:

• You can block all access, or allow access from specific IPv4 or IPv6 external IP ranges.
• It's not possible to configure the allowed IP ranges using private IP addresses.

Retrieving the web interface URL via the gcloud command-line tool

You can access the Airflow web interface from any web browser. To get the URL for the web interface, enter the following gcloud command:

gcloud composer environments describe ENVIRONMENT_NAME \
  --location LOCATION

Replace the following:

• ENVIRONMENT_NAME: the name of your environment.
• LOCATION: the region where the environment is located.

The gcloud command shows the properties of a Cloud Composer environment, including the URLs for the web interface. The URLs are listed as airflowUri and airflowByoidUri:

• The airflowUri URL address is used by Google accounts.
• The airflowByoidUri URL address is used by external identities if you configure Workforce identity federation in your project.

config:
  airflowUri: https://example-dot-us-central1.composer.googleusercontent.com
  airflowByoidUri: https://example-dot-us-central1.composer.byoid.googleusercontent.com

Restarting the web server

Preview — Web server restarting

This feature is subject to the "Pre-GA Offerings Terms" in the General Service Terms section of the Service Specific Terms. Pre-GA features are available "as is" and might have limited support. For more information, see the launch stage descriptions.

When debugging or troubleshooting Cloud Composer environments, some issues may be resolved by restarting the Airflow web server. You can restart the web server using the restartWebServer API or the restart-web-server gcloud command:

gcloud beta composer environments restart-web-server ENVIRONMENT_NAME \
  --location=LOCATION

Configuring web server network access

The Airflow web server access parameters don't depend on the type of your environment. Instead, you configure web server access separately. For example, a Private IP environment can still have the Airflow UI accessible from the internet.

It is not possible to configure the allowed IP ranges using private IP addresses.

Note: The Airflow web server of your environment is always protected by IAM, regardless of the IP ranges that are allowed to access it.

Caution: In some cases, changes to the web server access parameters can take up to 10 minutes to propagate.

Console

1. In the Google Cloud console, go to the Environments page.

   Go to Environments

2. In the list of environments, click the name of your environment. The Environment details page opens.

3. Go to the Environment configuration tab.

4. In the Network configuration section, find the Web server access control item and click Edit.

5. In the Web server network access control dialog:

   • To provide access to the Airflow web server from all IP addresses, select Allow access from all IP addresses.

   • To restrict access only to specific IP ranges, select Allow access only from specific IP addresses. In the IP range field, specify an IP range in the CIDR notation. In the Description field, specify an optional description for this range. If you want to specify more than one range, click Add IP range.

   • To forbid access for all IP addresses, select Allow access only from specific IP addresses and click Delete item next to the empty range entry.

gcloud

When you update an environment, the following arguments control web server access parameters:

• --web-server-allow-all provides access to Airflow from all IP addresses. This is the default option.

• --web-server-allow-ip restricts access only to specific source IP ranges. To specify several IP ranges, use this argument multiple times.

• --web-server-deny-all forbids access for all IP addresses.

Note: The Airflow web server of your environment is always protected by IAM, regardless of the IP ranges that are allowed to access it.

gcloud composer environments update ENVIRONMENT_NAME \
    --location LOCATION \
    --web-server-allow-ip ip_range=WS_IP_RANGE,description=WS_RANGE_DESCRIPTION

Replace the following:

• ENVIRONMENT_NAME: the name of your environment.
• LOCATION: the region where the environment is located.
• WS_IP_RANGE: the IP range, in the CIDR notation, that can access the Airflow UI.
• WS_RANGE_DESCRIPTION: the description of the IP range.

Example:

gcloud composer environments update example-environment \
    --location us-central1 \
    --web-server-allow-ip ip_range=192.0.2.0/24,description="office net 1" \
    --web-server-allow-ip ip_range=192.0.4.0/24,description="office net 3"

API

1. Construct an [environments.patch][api-patch] API request.

2. In this request:

   1. In the updateMask parameter, specify the config.webServerNetworkAccessControl mask.

   2. In the request body, specify how Airflow task logs must be saved:

      • To provide access to Airflow from all IP addresses, specify an empty config element (the webServerNetworkAccessControl element must not be present).

      • To restrict access only to specific IP ranges, specify one or more ranges in allowedIpRanges.

      • To forbid access for all IP addresses, specify an empty webServerNetworkAccessControl element. The webServerNetworkAccessControl element must be present, but must not contain an allowedIpRanges element.

Note: The Airflow web server of your environment is always protected by IAM, regardless of the IP ranges that are allowed to access it.

{
  "config": {
    "webServerNetworkAccessControl": {
      "allowedIpRanges": [
        {
          "value": "WS_IP_RANGE",
          "description": "WS_RANGE_DESCRIPTION"
        }
      ]
    }
  }
}

Replace the following:

• WS_IP_RANGE: the IP range, in the CIDR notation, that can access the Airflow UI.
• WS_RANGE_DESCRIPTION: the description of the IP range.

Example:

// PATCH https://composer.googleapis.com/v1/projects/example-project/
// locations/us-central1/environments/example-environment?updateMask=
// config.webServerNetworkAccessControl

{
  "config": {
    "webServerNetworkAccessControl": {
      "allowedIpRanges": [
        {
          "value": "192.0.2.0/24",
          "description": "office net 1"
        },
        {
          "value": "192.0.4.0/24",
          "description": "office net 3"
        }
      ]
    }
  }
}

Terraform

In the allowed_ip_range block, in the web_server_network_access_control specify IP ranges that can access web server.

Note: The Airflow web server of your environment is always protected by IAM, regardless of the IP ranges that are allowed to access it.

resource "google_composer_environment" "example" {
  provider = google-beta
  name = "ENVIRONMENT_NAME"
  region = "LOCATION"

  config {

    web_server_network_access_control {

      allowed_ip_range {
        value = "WS_IP_RANGE"
        description = "WS_RANGE_DESCRIPTION"
      }

    }

  }
}

Replace:

• WS_IP_RANGE with the IP range, in the CIDR notation, that can access Airflow UI.
• WS_RANGE_DESCRIPTION with the description of the IP range.

Example:

resource "google_composer_environment" "example" {
  provider = google-beta
  name = "example-environment"
  region = "us-central1"

  config {

    web_server_network_access_control {
      allowed_ip_range {
        value = "192.0.2.0/24"
        description = "office net 1"
      },
      allowed_ip_range {
        value = "192.0.4.0/24"
        description = "office net 3"
      }

    }
}

What's next

• Airflow UI Access Control
• Troubleshooting Airflow web server issues