2.20.16: Back to the 2.x Future

What's Changed

Bug Fixes 🐞

• backport retry delay type fix by @zzstoatzz in #16377
• Backport: deleting flows in python client prefect 2.0 by @paulusaptus in #16311
• Backport: Prevent workers from running flow runs scheduled for in process retry by @desertaxle in #16453

Integrations & Dependencies 🤝

• backport #16149 by @zzstoatzz in #16317
• Update typer requirement from !=0.12.2,<0.14.0,>=0.12.0 to >=0.12.0,!=0.12.2,<0.16.0 by @dependabot in #16207

Full Changelog: 2.20.15...2.20.16

3.1.9.dev2: Nightly Development Release

What's Changed

Integrations & Dependencies 🤝

• fix MattermostWebhook tests by @zzstoatzz in #16433

Development & Tidiness 🧹

• Update @prefecthq/prefect-ui-library to version 3.11.28 by @marvin-robot in #16437

Documentation 📓

• Add an example for creating an automation to mark zombie flow runs as crashed by @desertaxle in #16425
• Add a tutorial showing how to set up an email alert in Prefect Cloud by @daniel-prefect in #16345

Uncategorized

• Wrap OTLPLogExporter and OTLPSpanExporter in a QueueService to pull them out of the main thread by @bunchesofdonald in #16439
• Add redis causal ordering implementation by @zangell44 in #16416

Full Changelog: 3.1.9.dev1...3.1.9.dev2

3.1.9.dev1: Nightly Development Release

What's Changed

Bug Fixes 🐞

• fix passing enforce_parameter_schema in prefect deploy by @zzstoatzz in #16418

Full Changelog: 3.1.8...3.1.9.dev1

3.1.8: A Tale of Two Features

What's Changed

Runner Heartbeats for Flow Run Monitoring

Flow runs can now emit heartbeat events to detect infrastructure failures (crashed machines, evicted containers, etc). When enabled, an automation can automatically mark flows as crashed when heartbeats stop, preventing stuck "zombie" flows in the running state.

Enable with:

• Set PREFECT_RUNNER_HEARTBEAT_FREQUENCY (requires Prefect 3.1.8+)
• Deploy the provided automation script to update flow states when heartbeats stop

from prefect.automations import Automation
from prefect.client.schemas.objects import StateType
from prefect.events.actions import ChangeFlowRunState
from prefect.events.schemas.automations import EventTrigger, Posture

my_automation = Automation(
    name="Crash zombie flows",
    trigger=EventTrigger(
        after={"prefect.flow-run.heartbeat"},
        expect={
            "prefect.flow-run.heartbeat",
            "prefect.flow-run.Completed",
            "prefect.flow-run.Failed",
            "prefect.flow-run.Cancelled",
            "prefect.flow-run.Crashed",
        },
        match={"prefect.resource.id": ["prefect.flow-run.*"]},
        for_each={"prefect.resource.id"},
        posture=Posture.Proactive,
        threshold=1,
        within=90,
    ),
    actions=[
        ChangeFlowRunState(
            state=StateType.CRASHED,
            message="Flow run marked as crashed due to missing heartbeats.",
        )
    ],
)

my_automation.create()

Basic Authentication

We have also added a long requested feature: basic authentication support for the Prefect API. Enable by setting an auth string:

Start a protected server:

PREFECT_SERVER_API_AUTH_STRING="admin:admin" prefect server start

Authenticate client operations:

PREFECT_API_AUTH_STRING="admin:admin" python flow_script.py

Enhancements ➕➕

• Add working implementation of basic auth to server and client by @cicdw in #16408
• Add basic auth UI by @aaazzam in #16411
• Enhance Runner to send heartbeat events for flow runs by @desertaxle in #16410

Integrations & Dependencies 🤝

• add async redis client utils to prefect-redis by @zzstoatzz in #16417

Documentation 📓

• Add state change diagram by @mthatt in #16421

Full Changelog: 3.1.7...3.1.8

3.1.8.dev1: Nightly Development Release

What's Changed

Enhancements ➕➕

• Add working implementation of basic auth to server and client by @cicdw in #16408

Documentation 📓

• Enhance Runner to send heartbeat events for flow runs by @desertaxle in #16410

Full Changelog: 3.1.7...3.1.8.dev1

3.1.7: Straight outta Half Moon Bay

What's Changed

Enhancements ➕➕

• Support http proxies for websockets by @jakekaplan in #16326
• update contributor dev instructions by @zzstoatzz in #16376

Bug Fixes 🐞

• Fix missing terminal state timings for TimedOut tasks by @GalLadislav in #16328
• Early error on bad retry delay types by @cicdw in #16369
• [typing] add overload for empty @task decorator by @zzstoatzz in #16386
• Use websocket_connect utility in Subscriptions by @jakekaplan in #16388
• dont ask to confirm deletion of non-existent gcl by @zzstoatzz in #16379

Development & Tidiness 🧹

• Add Block.aload method and remove @sync_compatible from Block.load by @desertaxle in #16341
• Exclude UI v2 PRs from the release notes auto-generation by @desertaxle in #16344
• remove sync_compatible from git_clone by @zzstoatzz in #16340
• [typing] prefect.serializers by @desertaxle in #16331
• remove sync_compatible from prefect.variables by @zzstoatzz in #16349
• Consolidate use of DateTime to prefect.types by @zzstoatzz in #16356
• Fix type analysis check for PRs from forks by @desertaxle in #16359
• improve Dockerfile build time and add CI to catch future slow downs by @zzstoatzz in #16348
• Add buffer to type completeness check by @desertaxle in #16361
• only run docker build bench on push to main by @zzstoatzz in #16365
• [typing] prefect.tasks and prefect.task_worker by @zzstoatzz in #16332
• update entrypoint.sh to use uv for EXTRA_PIP_PACKAGES by @zzstoatzz in #16291
• update example output for prefect work-pool inspect by @zzstoatzz in #16378
• [typing] prefect.server.utilities.database by @mjpieters in #16368
• Pick up trace context from run labels by @bunchesofdonald in #16346
• Refactor db_injector decorator by @mjpieters in #16390
• Correctly maintain span hierarchy when instrumenting nested tasks/flows by @bunchesofdonald in #16384

Documentation 📓

• Remove missing page from the nav by @daniel-prefect in #16351
• Update flow run instrumentation to use RunTelemetry class by @jeanluciano in #16233
• Add experimental support for emitting lineage events by @abrookins in #16242
• update tutorial for clarity by @zzstoatzz in #16354

Full Changelog: 3.1.6...3.1.7

3.1.7.dev4: Nightly Development Release

What's Changed

Bug Fixes 🐞

• Use websocket_connect utility in Subscriptions by @jakekaplan in #16388

Uncategorized

• Refactor db_injector decorator by @mjpieters in #16390

Full Changelog: 3.1.7.dev3...3.1.7.dev4

3.1.7.dev3: Nightly Development Release

What's Changed

Enhancements ➕➕

• update contributor dev instructions by @zzstoatzz in #16376

Bug Fixes 🐞

• [typing] add overload for empty @task decorator by @zzstoatzz in #16386

Development & Tidiness 🧹

• update example output for prefect work-pool inspect by @zzstoatzz in #16378
• make re-usable TypeAdapter instances for client schemas by @zzstoatzz in #16089
• [typing] prefect.server.utilities.database by @mjpieters in #16368

Uncategorized

• dont ask to confirm deletion of non-existent gcl by @zzstoatzz in #16379

Full Changelog: 3.1.7.dev2...3.1.7.dev3

3.1.7.dev2: Nightly Development Release

What's Changed

Enhancements ➕➕

• Support http proxies for websockets by @jakekaplan in #16326

Bug Fixes 🐞

• Fix missing terminal state timings for TimedOut tasks by @GalLadislav in #16328
• Early error on bad retry delay types by @cicdw in #16369

Development & Tidiness 🧹

• Consolidate use of DateTime to prefect.types by @zzstoatzz in #16356
• Fix type analysis check for PRs from forks by @desertaxle in #16359
• improve Dockerfile build time and add CI to catch future slow downs by @zzstoatzz in #16348
• Add buffer to type completeness check by @desertaxle in #16361
• only run docker build bench on push to main by @zzstoatzz in #16365
• [typing] prefect.tasks and prefect.task_worker by @zzstoatzz in #16332
• update entrypoint.sh to use uv for EXTRA_PIP_PACKAGES by @zzstoatzz in #16291

Documentation 📓

• Update flow run instrumentation to use RunTelemetry class by @jeanluciano in #16233
• Add experimental support for emitting lineage events by @abrookins in #16242
• update tutorial for clarity by @zzstoatzz in #16354

Uncategorized

• Pick up trace context from run labels by @bunchesofdonald in #16346

Full Changelog: 3.1.7.dev1...3.1.7.dev2

3.1.7.dev1: Nightly Development Release

What's Changed

Development & Tidiness 🧹

• Exclude UI v2 PRs from the release notes auto-generation by @desertaxle in #16344
• remove sync_compatible from git_clone by @zzstoatzz in #16340
• [typing] prefect.serializers by @desertaxle in #16331
• remove sync_compatible from prefect.variables by @zzstoatzz in #16349

Documentation 📓

• Remove missing page from the nav by @daniel-prefect in #16351

Uncategorized

• Add Block.aload method and remove @sync_compatible from Block.load by @desertaxle in #16341
• Update release notes for tidiness by @cicdw in #16343

Full Changelog: 3.1.6...3.1.7.dev1