slack-prefect-to-orchestra

Overview

Prefect Slack notifications come in two forms:

1. Hooks / Automations (on_failure=, on_completion=, Prefect Automation Slack actions) — fire when the flow changes status; not pipeline steps.
2. Explicit messages inside a task (SlackWebhook.notify(), send_incoming_webhook_message(), or a plain @task calling slack_sdk.WebClient(...).chat_postMessage(...) directly) — a message sent at a specific point in the flow, called from the @flow body like any other task.

Watch for form 2 even when the task doesn't import prefect_slack at all — a task that just wraps slack_sdk.WebClient and is invoked as an explicit step (e.g. notify_slack(status) after an upstream task completes) is still a Slack notification, not generic Python. Converting it as a plain PYTHON_EXECUTE_SCRIPT task loses the Orchestra Slack connection wiring and the pipeline visibility of SLACK tasks.

In Orchestra these map to:

1. alerts: block (pipeline-level) — fires on status change; no pipeline slot consumed. Use for hooks/Automations.
2. SLACK pipeline task (integration: SLACK, integration_job: SEND_SLACK_MESSAGE) — fires at a specific position, when content depends on runtime logic or ordering matters. Use for explicit mid-flow messages, including raw slack_sdk calls.

SLACK IS a valid integration value and SEND_SLACK_MESSAGE IS a valid integration_job — Slack notifications should use one of these two native paths, not a generic HTTP_REQUEST task. Reach for HTTP_REQUEST only if the message is genuinely going to some other non-Slack webhook.

Parameter Mapping