Looker Connector: Install and Configure

Follow these steps to perform the necessary configuration for the Looker connector on the Looker side and in Alation.

Authentication Requirements

• Looker application registration credentials

• Looker Client ID and Client Secret

Looker Setup and Authentication

To access the Looker content and APIs, a Looker admin needs to enable Client ID and Client Secret access in the Looker Admin Portal:

1. Log in to Looker.

2. Navigate to the Admin Portal as shown below and choose users:

   

3. Create a new User to be used as a Service ID for integration needs, by clicking the Add Users button:

   

4. Enter an Email ID for the user and provide the appropriate roles and groups. The role must be Admin and the group assigned must have admin access:

   

5. Click the Add Users button.

6. Once the user is added, edit the user by clicking the Edit button for this user. The following screen will be displayed. Click Edit Keys:

   

7. Click New API3 Key button to generate a Client ID and Client Secret:

   

9. Note down the key and the secret as they are needed to configure the Looker connector in Alation.

Alation Setup and Authentication

STEP 1: Install the Connector

Important

Installation of an OCF connector requires Alation Connector Manager to be installed as a prerequisite.

1. If this has not been done on your instance, install Alation Connector Manager using the steps in: Install Alation Connector Manager.

2. Make sure that the OCF connector Zip file that you received from Alation is available on your local machine.

3. Install the connector on the Connectors Dashboard page: refer to Manage Connector Dashboard.

STEP 2: Create and Configure a New BI Server Source

Add a New BI Server Source

1. Log in to the Alation instance and add a new BI Server source: Apps > Sources > Add > BI Server. The Register a Business Intelligence Server screen will open.

2. On this screen, from the Select a Business Intelligence Server type list, select the Looker connector name and enter a Title and a Description:

   

3. Click Add. You will be navigated to your BI Server source Settings page.

Configure the Looker BI Source

Note

This section describes configuring settings for credentials and connection information stored in the Alation database. If your organization has configured Azure KeyVault or AWS Secrets Manager to hold such information, the user interface for the General Settings page will change to include the following icons to the right of most options:

By default, the database icon is selected, as shown. In the vault case, instead of the actual credential information, you enter the ID of the secret. See Configure Secrets for OCF Connector Settings for details.

Perform the configuration on the Settings page.

1. Specify Application Settings:

Parameter	Description
Disable Hard Sync	Leave this checkbox unselected. Selecting it will disable synchronization of BI objects between Alation and Looker. Note This is not applicable from version 2021.2
Disable Automatic Lineage Generation	Select the Disable Automatic Lineage Generation checkbox to skip the creation of automatic Lineage after extraction. When automatic Lineage generation is disabled, during extraction Alation does not calculate Lineage data for this BI source. For more information, see Automatic Lineage Generation FAQ. Note This is applicable from version 2021.3
Disable Permission Enforcement	Leave this checkbox selected. Permission enforcement is not supported between Looker and Alation.
Disable Certification	Leave this checkbox selected. Certification of BI objects in Looker from Alation is not supported.
Server URI	Enter the server URI used to access Looker.

2. Click Save to save the information you have entered.

3. Specify Connector Settings:

   Parameter	Description
   Looker API URL	Enter the API URL to access Looker APIs. Default URL is https://<Looker URI>:19999/
   Looker Client ID	Enter the Looker Client ID
   Looker Client Secret	Enter the Looker Client Secret
   Host	Provide the proxy host. This is an optional field and should be used only if Looker is connected using proxy connection.
   Display Images/Previews	Select this checkbox to preview the images of dashboards and reports.
   Disable Server Certification	Enable this checkbox to accept the Looker API url provided above without SSL checks.
   Server SSL Certificate Upload	Upload the SSL certificate if the Looker is a self-signed host or on-prem instance.
   Proxy URL	Specify the URL to access Looker via proxy server. This is an optional field and should be used only if Looker is connected using proxy connection.
   Proxy Port	Specify the proxy port number. Default proxy port number is 3128. This is an optional field and should be used only if Looker is connected using proxy connection.
   Proxy Username	Specify the proxy server username. This is an optional field and should be used only if Looker is connected using proxy connection.
   Proxy Password	Specify the proxy server password. This is an optional field and should be used only if Looker is connected using proxy connection.
   Log Level	Select the log level to generate logs. The available options are INFO, DEBUG, WARN, TRACE, ERROR, FATAL, ALL.

4. Click Save.

5. Under Test Connection, click Test to validate network connectivity. If the connector settings are good, a success message will be displayed.

6. Under Extraction Settings, configure the metadata extraction. Turn on Selective Extraction, if required. Selective extraction settings are used to apply a filter to include or exclude a list of Folders.

7. Click Get List of Projects to first fetch the list of Folders from Looker.

8. The status of the Get Projects action is logged in the Job History table at the bottom of the Settings page.

9. Once the folder synchronization is successful, a drop-down list of Folders will become enabled. Select one or more Folders to apply the filter.

10. Check if you are using the desired filter option. Available filter options are described below:

    Filter Option	Description
    Extract all Project except	Extract metadata from all Folders except from the Folders selected.
    Extract only these Projects	Extract metadata from only the selected Folders.

11. Click Run Extraction Now to extract metadata. The status of the Extraction action is also logged in the Job History table at the bottom of the page.

12. If you wish to automatically update the metadata in the Catalog, under Automated and Manual Extraction, turn on Enable Automated Extraction and select the day and time when metadata must be extracted. The metadata extraction will be automatically scheduled to run at the selected day and time.

Limitations

• Lineage is supported only for the following datasources:

  • Mysql

  • Sql server

  • Snowflake

  • Oracle

  • PostgreSQL

  • Amazon Redshift

  • Amazon Databricks

  • Azure Databricks

  • Google BigQuery

• Only client Id, client secret API based authentication is supported to extract metadata from Looker.

• We use api/4.0/vector_thumbnail/dashboard/<dashboard-id> to fetch images. If it do not return 200 response, then images will not be displayed.

• Incremental extraction is not supported.

• Proxy URL and port must be similar for both http and https connections.

• Explores extraction is not supported.

• DEBUG log level generates more logs and it use more disk space. It is recommended to use it only when gathering debug logs before raising a support ticket. For normal usage, we recommend to use INFO log level.

• LookML Dashboards are not cataloged by the connector.

Troubleshooting

Test Connection Failure

Verify that the Looker Client ID, Client Secret, and API URL are provided correctly on the Settings page. In most cases the Looker Base URL will be different from the API URL.

Limited Folders Shown in Alation

Check the user permissions in Looker. The user needs permissions to access all the folders.

Datasource Details are not Displayed in Alation

Check the user permissions in Looker. The user needs admin privileges. Without admin privileges datasource information cannot be extracted.

Datasource Column or Report Column Details are not Displayed in Alation

Check whether the models are published in Looker and they have content inside them. You can check whether the following API response contains an empty explores field, then columns will not show up, for example:

<Looker API URL>/api/3.1/lookml_models/<Model Name>

{
      "has_content": false,
      "label": "Crm",
      "name": "crm",
      "project_name": "crm",
      "unlimited_db_connections": false,
      "allowed_db_connection_names": [
          "mysql"
      ],
      "explores": [],
      "can": {
          "index": true,
          "show": true,
          "create": true,
          "update": true,
          "destroy": true
      }
}

Lineage is not Visible

If the lineage is not visible, make sure the datasource is cataloged in Alation and make sure the user has admin privileges.

Logs to be collected

Refer to Logs to be collected.