Release 3.0.0rc1

Release 3.0.0rc1

We're excited to announce the release candidate of Prefect 3.0. It's the most flexible, powerful, fastest version of Prefect yet. Prefect 3.0 includes several exciting new features. Install it by running pip install prefect==3.0.0rc1 and check out the docs here.

Run tasks independently of flows

You can now run and serve tasks outside of flows and inside of other tasks.

from prefect import task

@task
def my_background_task(name: str):
    print(f"Hello, {name}!")

if __name__ == "__main__":
    my_background_task.delay("ford")

Transactional semantics

Use rollback and commit hooks to facilitate idempotent python code.

from prefect import flow, task
from prefect.transactions import transaction
@task
def first_task():
    print('first')

@first_task.on_rollback
def roll(txn):
    print('rolling back')

@task
def second_task():
    raise RuntimeError("oopsie")

@flow
def txn_flow():
    with transaction():
        first_task()
        second_task()
if __name__ == "__main__":
    txn_flow()

Open source Events and Automations

Trigger actions, such as sending notifications, pausing schedules, starting flow runs and more in response to Prefect events.

More flexible variables and new artifact types

Variables can now be any JSON compatible type including dicts, lists, and integers. Progress and Image artifacts make it easy to add visual annotations to your flow run graph.

Faster and richer CLI

Improved CLI speed and several added commands and conveniences.

Updated navigation, styling, and interaction design

The new Runs page displays both flow and task run information, and an improved sidebar and switcher makes navigating Prefect simpler than ever.

Enhancements

• Create artifact for unsuccessful dbt task runs — #13348
• Add filter on task_run.expected_start_time — #13491
• Add utilities to serialize context to a dictionary and hydrate context from a dictionary — #13529
• Add API endpoints for deployment count and next flow run — #13544
• Allow flow parameter schema generation when dependencies are missing — #13315
• Change the default value for enforce_parameter_schema from False to True — #13594
• Migrate schemas to pydantic v2 — #13574
• Removes block auto-instrumentation — #13407
• Migrate all uses of the banned characters validation to a self-validator — #13370
• Ignore and warn on unrecognized settings - #13624

Fixes

• Remove unnecessary flow run infrastructure override access checks — #13401
• Enforce False case when flow run id is null — #13464
• Fix workspace variable hydration to allow for JSON data — #13548
• Remove unused settings/experimental work pool flags: PREFECT_EXPERIMENTAL_ENABLE_WORK_POOLS and PREFECT_EXPERIMENTAL_WARN_WORK_POOLS — #13144
• Pin pydantic>=2.7 for Secret — #13613
• Skip on cancellation hooks if runner can't load flow — #13660
• Refactor lazy imports to avoid accidental eager imports — #13296
• Allow block registration to use client schemas for server model creation — #13602
• Replace our customized Duration types with plain timedeltas — #13603

Experimental

• Add prefect.yaml and cli support for new schedule fields — #13318

Documentation

• Transition documentation hosting from Netlify to Mintlify — #13634
• Add Python 3.12 to list of Docker images — #13321
• Update index.md — #13353
• Improve tutorial section — #13297
• Fix jinja template in automations doc — #13422
• Update development section docs — #13247
• Update Ray integration docs — #13467
• Update Variables docs to include JSON types — #13493
• Update quickstart guide for usability — #13562
• Remove deployments-block-based concept page and refs for 3.0 — #13626
• Remove infrastructure concept page and refs for 3.0 — #13629
• Update docs image paths and remove outdated images — #13666
• Remove references to prefect.software from docs — #13382
• Update host.md — #13351
• Simplify rate limits page — #13689
• Removing references to deprecated block types and add disclaimer — #13651
• Update guides — #13253
• Remove storage concept page and refs - #13630

Integrations

• Migrate prefect-dbt to pydantic v2 - #13718
• Migrate prefect-email to pydantic v2 — #13654
• Migrate prefect-slack to pydantic v2 — #13673
• Migrate prefect-shell to pydantic v2 — #13675
• Migrate prefect-gcp to pydantic v2 — #13650
• Migrate prefect-github to pydantic v2 — #13655
• Migrate prefect-gitlab to pydantic v2 — #13656
• Migrate prefect-docker to pydantic v2 - #13697
• Migrate prefect-sqlalchemy to pydantic v2 - #13700
• Add PrefectDistributedClient to prefect-dask — #13537
• Update RayTaskRunner for compatibility with new engine — #13575
• Update DaskTaskRunner for compatibility with the updated engine — #13555
• prefect-dbt artifact consolidation and markdown fixes — #13379
• prefect-dbt - Cause unsuccessful dbt tasks to fail — #13405
• DBT Tasks extra_command_args Fix — #13308
• Update dbt-core dependency — #13394

Breaking Changes

• Remove prefect deployment build CLI from main — #13366
• Remove prefect agent CLI from main — #13365
• Remove prefect deployment apply CLI from main — #13367
• Remove PrefectAgent class — #13374
• Remove prefect.software — #13375
• Remove deployments module — #13373
• Remove EcsTask from main — #13417
• Remove AzureContainerInstanceJob from main — #13418
• Remove VertexAICustomTrainingJob from main — #13419
• Remove CloudRunJob from main — #13420
• Remove infrastructure blocks from main — #13424
• Remove Infrastructure, BlockWorker from main — #13430
• Remove deprecated storage blocks from main — #13410
• Remove prefect-agent as a possible work pool type — #13444
• Remove old engine — #13542
• Remove Python 3.8 support — #13331
• Remove deprecated module and its references — #13345
• Remove old task runners and futures modules — #13593
• Remove is_state — #13569
• Remove deprecated options from prefect work-queue and refs to agents - #13638

Contributors

• @bsignoret

• @jaraics made their first contribution in #13144

All changes: 2.19.0...3.0.0rc1

See release notes for details.

Release 2.19.3

New method for generating parameter schemas without dependencies

prefect deploy now works even when dependencies are missing from the current environment. This can speed up deployment via CI by removing the need to install dependencies before deploying your flows.

See the following pull requests for implementation details:

• #13620
• #13315

Enhancements

• Provide URL in CLI output upon work pool creation — #13597

Fixes

• Ensure graceful cancellation of flow runs corresponding to deleted deployments — #13669

Integrations

• Add loading state to concurrency limits table in the Prefect UI — PrefectHQ/prefect-ui-library#2483
• Remove old schema properties from deployments in the Prefect UI — PrefectHQ/prefect-ui-library#2482
• Add handling for multi-word dbt CLI commands — #13616

All changes: 2.19.2...2.19.3

Release 2.19.2

This release includes a few bug fixes, ensuring:

• 🛠️ runs created from the deployments/{id}/create_flow_run endpoint hydrates workspace variables
• 🔢 proper integer value display on the Variables page of the Prefect UI — PrefectHQ/prefect-ui-library#2454
• ⚙️ "Run a deployment" automation action parameter display input configuration persists during editing — PrefectHQ/prefect-ui-library#2458
• 📌 requests dependency pinned to <2.32.0 in requirements-dev.txt - #13538
• 📄 Jinja template example is renderable in automations documentation — #13421

2.19.1

Release 2.19.1

Enhancements to prefect-dbt for running dbt-core commands

Introducing prefect-dbt summary artifacts! With summary artifacts, you get a view of all of the runs that succeeded, failed, or were skipped as well as where the failed models live in your dbt project and why they failed. This exposes information about each dbt node in a succinct format that teams can use for development, debugging, insights, and so much more.

These changes are available in prefect-dbt version 0.5.0!

See the following pull requests for implementation details:

• #12964
• #13387
• #13406

Enhancements

• Enable flow run infra overrides section in the Prefect UI - PrefectHQ/prefect-ui-library#2417

Experimental

Events and Automations

• Add ability to create and manage automations in the Prefect UI - #13342

Documentation

• Update documentation formatting for prefect-ray - #13385

Integrations

• Update all integrations libraries to pin prefect<3.0.0 - #13408

Integration library releases

This release was accompanied by the following integration library releases:

• prefect-aws - 0.4.17
• prefect-azure - 0.3.10
• prefect-bitbucket - 0.2.5
• prefect-dask - 0.2.9
• prefect-databricks - 0.2.7
• prefect-dbt - 0.5.0
• prefect-docker - 0.5.2
• prefect-email - 0.3.5
• prefect-gcp - 0.5.12
• prefect-github - 0.2.5
• prefect-gitlab - 0.2.5
• prefect-kubernetes - 0.3.10
• prefect-ray - 0.3.6
• prefect-shell - 0.2.5
• prefect-slack - 0.2.6
• prefect-snowflake - 0.27.6
• prefect-sqlalchemy - 0.4.3

All changes: 2.19.0...2.19.1

Release 2.19.0

✨ This release includes a number of enhancements and fixes!

Support for major infrastructure and distributed task integrations

As prefect-dask and other integrations have been added to the prefect codebase, this release adds these integrations as extra requirements of the prefect package, making it easier to install support for everything in your Prefect stack:

pip install 'prefect[dask]'

We loved this community contribution so much, we did it for all our first-party integrations:

pip install 'prefect[aws,kubernetes,dask,dbt,sqlalchemy,slack]'

You can see the full list of Prefect's extra requirements in our setup.py.

Support for timeout seconds in global concurrency context manager

You may want to fail immediately if a global concurrency slot is unavailable. Rather than block and wait, you can now specify a timeout_seconds argument in the global concurrency context manager and catch a TimeoutError if a slot is not available within the specified time.

@flow
def fail_immediately_flow():
    try:
        with concurrency("there-can-be-only-one", occupy=1, timeout_seconds=0.1):
            do_something_resource_intensive()
    except TimeoutError:
        return Cancelled(message="Another flow run is already running")

Manage global concurrency limits via the CLI

Global concurrency limits let you control how many operations can run simultaneously-- now you can create, read, edit, and delete global concurrency limits via the Prefect CLI!

To create a new concurrency limit, use the prefect gcl create command. You must specify a --limit argument, and can optionally specify a --slot-decay-per-second and --disable argument.

prefect gcl create my-concurrency-limit --limit 5 --slot-decay-per-second 1.0

You can inspect the details of a concurrency limit using the prefect gcl inspect command:

prefect gcl inspect my-concurrency-limit

To update a concurrency limit, use the prefect gcl update command. You can update the --limit, --slot-decay-per-second, --enable, and --disable arguments:

prefect gcl update my-concurrency-limit --limit 10

We also have many more bug fixes and in-flight work! See the release notes for details!

Release 2.18.3

Experimental

Engine

• Wire up new engine to deployment runs — #12914

Fixes

• Fix parameters becoming unresponsive and disappearing in Prefect UI — PrefectHQ/prefect-ui-library#2355

All changes: 2.18.2...2.18.3

Release 2.18.2

💡 Providing a deployment name to flow.serve is now optional

When running flow.serve, you can now omit the deployment name. If you do not provide a deployment name, the deployment name will default to the name of the flow. This change makes it easier to run flows without needing to specify a deployment name each time:

@flow
def etl_flow():
    pass

if __name__ == "__main__":
  etl_flow.serve()

results in:

Your flow 'etl-flow' is being served and polling for scheduled runs!

To trigger a run for this flow, use the following command:

        $ prefect deployment run 'etl-flow/etl-flow'

🛠✨ We've also released a few important fixes to our deployment parameter form when creating a run in the Prefect UI! 🧑‍🎨

🚀 This release also includes a number of other fixes and in-flight feature work. See the release notes for more details!

Release 2.18.1

Release 2.18.1

Fixes

• Fix improper context access for nested async task outside of flow — #12810
• Fix using default interval schedule in prefect deploy — #12833
• Handle case in validationUpdate schema where definitions are falsy — #12880
• Allow prefect cloud login to override current workspace — #12867
• Remove extra quotes in prefect deployment run --watch — #12894

Experimental

Events and Automations

• Support filtering by automation name:
  • #12850
  • #12884
  • #12887
• Add support for using the "normal" Trigger classes for flow.serve and .deploy — #12789
• Add an account-level event subscriber — #12808
• Emit flow run state change events — #12825
• Emit deployment status persistence and events — #12853
• Enable event streaming from PrefectCloudEventSubscriber via CLI — #12796
• Update the prefect automation delete CLI — #12876

Engine

• Add new experimental engine for tasks and flows with improved readability and extensibility — #12856

Documentation

• Improve installation instructions — #12783
• Improve quickstart — #12798
• Migrate prefect-azure docs to Integrations section of the Prefect docs — #12794
• Update storage guide credentials blocks — #12819
• Remove server import recommendations — #12823
• Remove link to removed API page — #12824
• Add Azure Container Instances worker guide — #12846
• Improve wording on integrations index page — #12852

Prefect UI Library

• Add FormattedDate component to display accessible, long-form timestamps consistently
• Update modal buttons and add auto-close to the parameters and job variable modals — PrefectHQ/prefect-ui-library#2320
• Add flow run list information density — PrefectHQ/prefect-ui-library#2321
• Fix "Run a deployment" action not populating the default parameters from the deployment — PrefectHQ/prefect-ui-library#2322
• Fix schema form properties with no default value from defaulting to null (None) — PrefectHQ/prefect-ui-library#2323
• Update date-fns and date-fns-tz — PrefectHQ/prefect-ui-library#2319
• Use correct icon colors for non-destructive actions in the UI — PrefectHQ/prefect-ui-library#2328

Integrations

Prefect CGP

• Remove API ref to nonexistent Google Cloud Run V2 page — PrefectHQ/prefect-gcp#260
• Fix VPC access for Cloud v2 worker — PrefectHQ/prefect-gcp#266
• Handle case where vpc isn't in job template — PrefectHQ/prefect-gcp#267

New Contributors

• @keizobabybear made their first contribution in #12852

Release 2.18.0

Breaking Changes

• Remove deprecated ability to use deployment.yaml in prefect deploy — #12731
• Remove deprecated ability to pass -f/--flow as option to prefect deploy — #12732
• Remove deprecated projects from prefect deploy — #12737
• Remove deprecated --ci option from prefect deploy — #12740

Enhancements

• Improve account selection in prefect cloud login and workspace set — #12717

Full Changelog: 2.17.0...2.18.0

See the release notes for more!

Release 2.17.1

Fixes

• Fix events storage import — #12681
• Remove opentelemetry import — #12684

All changes: 2.17.0...2.17.1