How to send to a mailing list

About

This howto shows you how to send multiple email with the sendmail operation.

Steps

Start the howto smtp server

tabul service start smtp

1 service was started
Name   Type
----   ------
smtp   docker

Check that you can ping it

tabul connection ping smtp

The connection (smtp) has been pinged successfully

Pipeline

In this pipeline, we define a inline data resource but you can use any data resources (a select query, a csv, …) where each column corresponds to a sendmail attributes.

kind: pipeline
spec:
  steps:
    - name: "Define"
      comment: "This operation defines a data path with the expected columns of a mailing list"
      operation: "define"
      args:
        data-resource:
          data-def:
            columns: [ "to","from","subject","txt","html" ]
          data-records:
            - [ "[email protected]", "[email protected]", "Email for foo", "A textual email body", "<html><body><h1>A html email body</h1></body></html>" ]
            - [ "[email protected]", "[email protected]", "Email for bar", "A textual email body", "<html><body><h1>A html email body</h1></body></html>" ]
    - name: "Send"
      comment: "Send the email"
      operation: "sendmail"
      args:
        target-uri: "@smtp" # smtp is the default smtp connection and is therefore optional
        granularity: "record"

Execution

If you execute this pipeline

tabul flow execute pipeline/email_list.yml@howto

Output:

Execution Metrics of the pipeline (email_list)
metrics                  value
----------------------   -----------------------------------------------------
pipeline-path            /opt/tabulify/resources/howto/pipeline/email_list.yml
processing-type          batch
start-time               2025-11-10T20:01:55.194989764Z
end-time                 2025-11-10T20:01:55.322621467Z
total-elapsed-time       0.128s
execution-elapsed-time   0.128s



Step execution results for the pipeline (email_list)
step_id   step_name   operation_name   operation_type   processing_type   input_counter   output_counter   execution_counter   error_counter   parking_counter
-------   ---------   --------------   --------------   ---------------   -------------   --------------   -----------------   -------------   ---------------
      1   Define      define           Supplier         batch                         0                1                   0               0                 0
      2   Send        sendmail         Map              stream                        1                1                   1               0                 0

Check the Inbox

In the mailpit inbox, you can then see the 2 emails.