Deploy a scheduled Checkpoint with cron

This guide will help you deploy a scheduled CheckpointThe primary means for validating data in a production deployment of Great Expectations. with cron.

Prerequisites

• Completion of the Quickstart guide.
• A working installation of Great Expectations.
• A Great Expectations instance.
• A Checkpoint.

Verify Checkpoint suitability

Run the following command to verify that your Checkpoint runs:

checkpoint = context.get_checkpoint("taxi_checkpoint")
checkpoint.run()

Get great_expectations full path

To prepare for editing the cron file, you'll need the full path of the project's great_expectations directory. You can get full path to the great_expectations executable by running:

which great_expectations
/full/path/to/your/environment/bin/great_expectations

Open your cron schedule

A text editor can be used to open the cron schedule. On most operating systems, crontab -e will open your cron file in an editor.

Add your Checkpoint to the cron schedule

To run the Checkpoint my_checkpoint every morning at 0300, add the following line in the text editor that opens:

0  3  *  *  *    /full/path/to/your/environment/bin/great_expectations checkpoint run ratings --directory /full/path/to/my_project/gx/

note

• The five fields at the start of your cron schedule correspond to the minute, hour, day of the month, month, and day of the week.
• It is critical that you use full paths to both the great_expectations executable in your project's environment and the full path to the project's gx/ directory.

Save your changes to the cron schedule

Once you have added the line that runs your Checkpoint at the desired time, save the text file of the cron schedule and exit the text editor.