Scheduled Rollup

Breyta scheduled workflow example for cron-triggered rollup jobs.

Quick Answer

Use a :schedule trigger with cron config and :concurrency :drain for predictable handover between flow versions.
Use a top-level function for output shaping, keeping the :flow body orchestration-only and labeling orchestration branches.

Use Case

Run periodic aggregation on a schedule.

Full Definition

{:slug :scheduled-rollup
 :name "Scheduled Rollup"
 :concurrency {:type :singleton :on-new-version :drain}
 :functions [{:id :build-rollup-output
              :language :clojure
              :code "(fn [input] {:type :rollup :run-at (:run-at input) :input (:input input)})"}]
 :triggers [{:type :schedule
             :label "Every 15m"
             :enabled true
             :config {:cron "*/15 * * * *"}}]
 :flow
 '(let [run-at (flow/step :time :now {})
        input (flow/input)
        rollup-input ^{:label "Rollup input source"
                       :yes "Use override payload"
                       :no "Use schedule/manual input"}
                     (if (:override input)
                       (:override input)
                       input)
        output (flow/step :function :build-output
                 {:ref :build-rollup-output
                  :input {:run-at run-at
                          :input rollup-input}})]
    output)}

Expected Behavior

A new run executes on schedule and produces rollup payload metadata.

Notes

Use :drain when overlapping versions should finish before switching.

Operational guidance:

schedule trigger means runs are time-based, not manually started by default
choose a short cron interval in non-prod during validation
keep output lightweight for periodic workloads
:drain lets in-flight runs finish before a new released version takes over

Validation tip: