docs/liminal/pipelines.md

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# Pipelines

In the `pipelines` section you can configure scheduled/manually run pipelines of tasks to be
executed sequentially:

```yaml
pipelines:
  - pipeline: my_data_pipeline
    timeout_minutes: 30
    start_date: 2020-03-01
    schedule: 0 10 * * *
    tasks:
      - task: my_sql_task
        type: sql
        query: "SELECT * FROM
        {{my_database_name}}.{{my_table_name}}
        WHERE event_date_prt >=
              '{{yesterday_ds}}'"
              AND cms_platform = 'xsite'
        output_table: my_db.my_out_table
        output_path: s3://my_bky/{{env}}/mydir
      - task: my_python_task
        type: python
        image: myorg/myrepo:pythonapp
        cmd: python my_python_app.py
        env_vars:
          env: {{env}}
          fizz: buzz
```

`pipelines` is a section in the root lof your liminal.yml file and is a list of `pipeline`s defined
by the following attributes:

## pipeline attributes

`pipeline`: name of your pipeline (must be unique per liminal server).

`timeout_minutes`: maximum allowed pipeline run time in minutes, if run exceeds this time, pipeline
and all running tasks will fail.

`start_date`: start date for the pipeline.

`schedule`: to be configured if the pipeline should run on a schedule. Format is
[cron expression](https://en.wikipedia.org/wiki/Cron#CRON_expression).

`tasks`: list of `task`s, defined by the following attributes:

## task attributes

For fully detailed information on tasks see: [tasks](tasks).

`task`: name of your task (must be made of alphanumeric, dash and/or underscore characters only).

`type`: type of the task. Examples of available task types are: `python`.
and more..

Different task types require their own additional configuration. For example, `python` task requires
`image` to be configured.