Variables in Batch Job

Variables in Batch Job – In Mule 4 Batch processing if a variable is defined in batch step then it will be tied to the record in process and will be present throughout the record processing i.e. throughout all consecutive batch steps. Sequence is followed so variable declared in Batch Step will only be available in succeeding Batch Steps

In below table we can see the example where if Variable is defined or updated in any of the batch step then it will be available throughout the consecutive Batch Steps

For POC we will initialize the variable in first Batch Step and Log the values in later Batch Steps

Initialize orderId to Order ID in payload

Let’s print the value in succeeding Batch Steps

In last Batch Step

If we run the application for 3 records then we can see the logs getting printed with correct Order ID

INFO  2020-06-08 12:59:59,774 [[MuleRuntime].io.05: [batch-job-sample].batch-job-batch-job-sample_Batch_Job-work-manager @7729c08a] [event: dbfee500-a959-11ea-9812-9aaf65ed66d8] 
org.mule.runtime.core.internal.processor.LoggerMessageProcessor: 669165933 - Processed
INFO  2020-06-08 12:59:59,777 [[MuleRuntime].io.05: [batch-job-sample].batch-job-batch-job-sample_Batch_Job-work-manager @7729c08a] [event: dbfee500-a959-11ea-9812-9aaf65ed66d8] 
org.mule.runtime.core.internal.processor.LoggerMessageProcessor: 963881480 - Processed
INFO  2020-06-08 12:59:59,813 [[MuleRuntime].io.05: [batch-job-sample].batch-job-batch-job-sample_Batch_Job-work-manager @7729c08a] [event: dbfee500-a959-11ea-9812-9aaf65ed66d8] com.mulesoft.mule.runtime.module.batch.internal.DefaultBatchStep: Step Batch_Step_Processed_Records finished processing all records for instance dbff0c10-a959-11ea-9812-9aaf65ed66d8 of job batch-job-sample_Batch_Job
INFO  2020-06-08 12:59:59,816 [[MuleRuntime].io.08: [batch-job-sample].batch-job-batch-job-sample_Batch_Job-work-manager @7729c08a] [event: dbfee500-a959-11ea-9812-9aaf65ed66d8] 
org.mule.runtime.core.internal.processor.LoggerMessageProcessor: 341417157 - Failed
INFO  2020-06-08 12:59:59,817 [[MuleRuntime].io.08: [batch-job-sample].batch-job-batch-job-sample_Batch_Job-work-manager @7729c08a] [event: dbfee500-a959-11ea-9812-9aaf65ed66d8] org.mule.runtime.core.internal.processor.LoggerMessageProcessor: failed record found Region,Country,Item Type,Sales Channel,Order Priority,Order Date,Order ID,Ship Date,Units Sold,Unit Price,Unit Cost,Total Revenue,Total Cost,Total Profit
Europe,Russia,Office Supplies,Offline,L,5/2/2014,341417157,5/8/2014,1779,651.21,524.96,1158502.59,933903.84,224598.75

Sample mule application: batch-job-sample-variables

Sample CSV – Sample