Creating a reusable pipeline

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This tutorial shows how to build a reusable pipeline that reads data from Cloud Storage, performs data quality checks, and writes to Cloud Storage.

Reusable pipelines have a regular pipeline structure, but you can change the configuration of each pipeline node based on configurations provided by an HTTP server. For example, a static pipeline might read data from Cloud Storage, apply transformations, and write to a BigQuery output table. If instead you want the transformation and BigQuery output table to change based on the Cloud Storage file that the pipeline reads, you create a reusable pipeline.

Objectives

• Use the Argument Setter plugin to allow the pipeline to read different input in every run.
• Use the Argument Setter plugin to allow the pipeline to perform different quality checks in every run.
• Write the output data of each run to Cloud Storage.

Costs

This tutorial uses the following billable components of Google Cloud:

• Cloud Data Fusion
• Cloud Storage

To generate a cost estimate based on your projected usage, use the pricing calculator. New Google Cloud users might be eligible for a free trial.

Before you begin

1. Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.

2. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

3. Make sure that billing is enabled for your Cloud project. Learn how to check if billing is enabled on a project.

4. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

5. Make sure that billing is enabled for your Cloud project. Learn how to check if billing is enabled on a project.

6. Enable the Cloud Data Fusion, Cloud Storage, and Cloud Dataproc APIs.

   Enable the APIs

7. Create a Cloud Data Fusion instance.

Navigate to the Cloud Data Fusion UI

When using Cloud Data Fusion, you use both the Google Cloud console and the separate Cloud Data Fusion UI. In the Google Cloud console, you can create a Google Cloud console project, and create and delete Cloud Data Fusion instances. In the Cloud Data Fusion UI, you can use the various pages, such as Pipeline Studio or Wrangler, to use Cloud Data Fusion features.

1. In the Google Cloud console, open the Instances page.

   Open the Instances page

2. In the Actions column for the instance, click the View Instance link. The Cloud Data Fusion UI opens in a new browser tab.

Deploy the Argument Setter plugin

1. In the Cloud Data Fusion web UI, click Hub in the upper right.

2. Click the Argument setter action plugin and click Deploy.

3. In the Deploy window that opens, click Finish.

4. Click Create a pipeline. The Pipeline Studio page opens.

Read from Cloud Storage

1. In the left panel of the Pipeline Studio page, using the Source drop-down menu , select Google Cloud Storage.
2. Hover over the Cloud Storage source card and click the Properties button that appears.

   

3. In the Reference name field, enter a name.
4. In the Path field, enter ${input.path}. This macro controls what the Cloud Storage input path will be in the different pipeline runs.
5. In the right Output Schema panel, remove the offset field from the output schema by clicking the trash icon in the offset field row.

   

6. Click Validate to make sure you don't have any errors.
7. Click the X button to exit the Properties dialog box.

Transform your data

1. In the left panel of the Pipeline Studio page, using the Transform drop-down menu , select Wrangler.
2. In the Pipeline Studio canvas, drag an arrow from the Cloud Storage card to the Wrangler card.

   

3. Hover over the Wrangler card and click the Properties button that appears.
4. In the Input field name, enter body.
5. In the Recipe field, enter ${directives}. This macro controls what the transform logic will be in the different pipeline runs.

   

6. Click Validate to make sure you don't have any errors.
7. Click the X button to exit the Properties dialog box.

Write to Cloud Storage

1. In the left panel of the Pipeline Studio page, using the Sink drop-down menu , select Cloud Storage.
2. In the Pipeline Studio canvas, drag an arrow from the Wrangler card to the Cloud Storage card you just added.

   

3. Hover over the Cloud Storage sink card and click the Properties button that appears.
4. In the Reference name field, enter a name.
5. In the Path field, enter the path of a Cloud Storage bucket in your project, where your pipeline can write the output files. If you don't have a Cloud Storage bucket, create one.

   

6. Click Validate to make sure you don't have any errors.
7. Click the X button to exit the Properties menu.

Set the macro arguments

1. In the left panel of the Pipeline Studio page, using the Conditions and Actions drop-down menu , select the Argument Setter plugin.
2. In the Pipeline Studio canvas, drag an arrow from the Argument Setter card to the Cloud Storage source card.

   

3. Hover over the Argument Setter card and click the Properties button that appears.

4. In the URL field, enter the following.

   https://storage.googleapis.com/reusable-pipeline-tutorial/args.json
   

   The URL corresponds to a publicly accessible object in Cloud Storage that contains the following content:

   {
     "arguments" : [
       {
         "name": "input.path",
         "value": "gs://reusable-pipeline-tutorial/user-emails.txt"
       },
       {
         "name": "directives",
         "value": "send-to-error !dq:isEmail(body)"
       }
     ]
   }
   

   The first of the two arguments is the value for input.path. The path gs://reusable-pipeline-tutorial/user-emails.txt is a publicly accessible object in Cloud Storage that contains the following test data:

   [e-mail]
   [e-mail]
   craig@[e-mail]
   

   The second argument is the value for directives. The value send-to-error !dq:isEmail(body) configures Wrangler to filter out any lines that are not a valid email address. For example, craig@[e-mail] is filtered out.

5. Click Validate to make sure you don't have any errors.

6. Click the X button to exit the Properties menu.

Deploy and run your pipeline

1. In the top bar of the Pipeline Studio page, click Name your pipeline. Name your pipeline and click Save.
2. Click Deploy.
3. Next to Run, click the drop-down menu to open the Runtime Arguments and view the macro (runtime) input.path and directives arguments. Leave the value fields blank to notify Cloud Data Fusion that the Argument Setter node in the pipeline will set the values of these arguments during runtime.

   

4. Click Run.

Clean up

To avoid incurring charges to your Google Cloud account for the resources used in this tutorial, either delete the project that contains the resources, or keep the project and delete the individual resources.

After you've finished the tutorial, clean up the resources you created on Google Cloud so they won't take up quota and you won't be billed for them in the future. The following sections describe how to delete or turn off these resources.

Delete the Cloud Data Fusion instance

Follow the instructions to delete your Cloud Data Fusion instance.

Delete the project

The easiest way to eliminate billing is to delete the project that you created for the tutorial.

To delete the project:

Caution: Deleting a project has the following effects:

• Everything in the project is deleted. If you used an existing project for this tutorial, 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.

If you plan to explore multiple tutorials and quickstarts, reusing projects can help you avoid exceeding project quota limits.

1. In the Google Cloud console, go to the Manage resources page.

   Go to Manage resources

2. In the project list, select the project that you want to delete, and then click Delete.
3. In the dialog, type the project ID, and then click Shut down to delete the project.

What's next

• Read the how-to guides
• Work through another tutorial