Logging

Set the transformation logging level ..

Workshop - Logging

Use logging to diagnose transformation problems. Create a controlled type mismatch error. Use log level and output to find the cause.

What you’ll do

• Change field metadata to trigger an error
• Run with Basic and Row level logging
• Use Execution results to find the failing step
• Locate the same error in pdi.log

Prerequisites: Complete the Hello World workshop

Estimated time: 5 minutes

Logging

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Create a new transformation

Use any of these options to open a new transformation tab:

• Select File > New > Transformation
• Use Ctrl+N (Windows/Linux) or Cmd+N (macOS)

Logging

tr_hello_world.ktr

15KB

Open

1. Modify Generate Rows

Start from the transformation you built in Hello World.

Generate Rows

Generate Rows is a test-data step. It is a quick way to validate logging and error handling.

To create an error, change the field type for message from String to Integer.

1. Double-click the Generate Rows step.
2. Change the type for message to Integer.

Change data type

1. Select OK.

2. Run

Run the transformation

Run with a higher log level to see row-level detail.

1. Select Run in the canvas toolbar.
2. Set Log level to Basic.
3. Select Run.
4. Run again with Log level set to Row level.

Set row level debugging

1. Select Run. The failing step is highlighted.

Error in step

1. In Execution results, open the Log tab.

Logging - error

The error text is in the log output. Look for the first ERROR entry.

Tip: Select the minus icon to show errors only.

The same error is written to pdi.log:

Windows

C:\\Pentaho\\design-tools\\data-integration\\logs\\pdi.log

macOS / Linux

~/Pentaho/design-tools/data-integration/logs/pdi.log

pdi.log - Linux

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Next workshop: Error Handling