Obtain logging information

When you need more information about how transformations and jobs execute, you can view PDI log lines and text.

PDI collects log lines in a central place. The org.pentaho.di.core.logging.KettleLogStore class manages all log lines and provides methods for retrieving the log text for specific entities. To retrieve log text or log lines, supply the log channel ID generated by PDI during runtime. You can obtain the log channel id by calling getLogChannelId(), which is part of LoggingObjectInterface. Jobs, transformations, job entries, and transformation steps all implement this interface.

For example, assuming the job variable is an instance of a running or completed job, the following code shows how you retrieve the job's log lines:

LoggingBuffer appender = KettleLogStore.getAppender();
String logText = appender.getBuffer(job.getLogChannelId(), false).toString();

The main methods in the sample classes org.pentaho.di.sdk.samples.embedding.RunningJobs and org.pentaho.di.sdk.samples.embedding.RunningTransformations retrieve log information from the executed transformation or job in this manner.