dagster-slack

library0.29.20pypypi✓ verified 26d ago

The `dagster-slack` library provides a Slack client resource for integrating Slack notifications and messaging capabilities into Dagster data pipelines. It enables users to send messages to Slack channels from ops, assets, schedules, and sensors, facilitating real-time communication about pipeline status and events. The current version is 0.29.0, and it follows the frequent release cadence of the broader Dagster ecosystem.

workflow communication data

pip install dagster-slack

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · DAGSTER-SLACK

dagster-slack

workflowpythonv0.29.20

Install

13.4s avg

Import

3075ms

Disk

139MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.29.20 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 3.214s · 136.9MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 13.4s · import 2.936s · 133MB

139MB installed

● package 139MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

SlackResource

✓ from dagster_slack import SlackResource

make_slack_on_run_failure_sensor

✓ from dagster_slack import make_slack_on_run_failure_sensor

make_slack_on_step_failure_hook

✓ from dagster_slack import make_slack_on_step_failure_hook

This quickstart demonstrates how to define a `SlackResource` with a Slack bot token (loaded from an environment variable) and then use it within a Dagster asset to post a message to a specified Slack channel. A Slack App and bot token are required for this to function.

import os from dagster import Definitions, EnvVar, asset from dagster_slack import SlackResource @asset def send_slack_message(slack: SlackResource): """An asset that sends a message to Slack.""" channel = os.environ.get('SLACK_CHANNEL', '#general') # Ensure channel exists slack.get_client().chat_postMessage(channel=channel, text=":wave: Hello from Dagster!") defs = Definitions( assets=[send_slack_message], resources={ "slack": SlackResource(token=EnvVar("MY_SLACK_TOKEN")) }, )

Debug

Known issues

gotchaWhen interacting with the Slack client directly from the `SlackResource`, use `slack.get_client().chat_postMessage(...)` instead of `slack.chat_postMessage(...)`. The `get_client()` method ensures you are calling the method on the underlying `slack_sdk.WebClient` instance.

fix

Always call `.get_client()` on the `SlackResource` instance before invoking Slack API methods.

affects: All versions

breakingWhen configuring hooks and sensors (e.g., `make_slack_on_run_failure_sensor`), the `dagit_base_url` parameter has been deprecated and replaced with `webserver_base_url` for generating deep links to runs in the UI.

fix

Update `dagit_base_url` parameters to `webserver_base_url` in your sensor and hook definitions.

affects: Dagster core 1.3.x and later, corresponding dagster-slack versions

gotchaTo use `dagster-slack`, you must first create a Slack App in your workspace, configure bot users, install the app to your workspace, and obtain a bot token. This token should be stored securely, ideally as an environment variable (e.g., `MY_SLACK_TOKEN`), and passed to the `SlackResource`.

fix

Follow the official Slack App creation and token generation guide to set up your integration.

affects: All versions

deprecatedIn `make_slack_on_run_failure_sensor`, the `job_selection` and `monitor_all_repositories` parameters are deprecated. Use `monitored_jobs` for specifying jobs to monitor.

fix

Migrate from `job_selection` to `monitored_jobs` in `make_slack_on_run_failure_sensor` definitions.

affects: Dagster core 1.12.14 / dagster-slack 0.28.14 and later (implied)

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'dagster_slack'

The `dagster-slack` library is not installed in the Python environment where Dagster is running.

fix

Run `pip install dagster-slack` to install the library.

slack_sdk.errors.SlackApiError: The request to the Slack API failed. (url: https://www.slack.com/api/chat.postMessage) The server responded with: {'ok': False, 'error': 'invalid_auth'}

The Slack token provided to `SlackResource` is invalid, revoked, or lacks the necessary permissions to authenticate with the Slack API.

fix

Ensure your Slack bot token (starts with `xoxb-`) is correct, has the `chat:write` scope (and `chat:write.public` if posting to public channels), and is passed correctly to the `SlackResource` (e.g., via `EnvVar`).

The server responded with: {'ok': False, 'error': 'not_in_channel'}

The Slack bot associated with the provided token has not been invited to the target Slack channel.

fix

Invite your Slack bot to the desired channel by typing `/invite @your-bot-name` in the Slack channel, or add it via the channel's integration settings.

dagster.core.errors.DagsterInvalidConfigError: Missing required config entry 'token' at path root:resources:slack:config

The `SlackResource` requires a `token` configuration, which was not provided when defining the resource.

fix

Provide the Slack token (e.g., via an environment variable) when defining your `SlackResource` in your Dagster definitions. For example: `SlackResource(token=EnvVar('SLACK_BOT_TOKEN'))`.

Upgrade

Version history

0.29.20latest on PyPI · released Aug 27, 2026

Audit

Dependencies

dagsterrequiredCore dependency for Dagster integrations and resources.

Agent activity

29 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/dagster-io/dagster ↗

packagehttps://pypi.org/project/dagster-slack/ ↗

homepagehttps://dagster.io ↗