blueprints: watch blueprints directory and trigger tasks (#4309)

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

authentik/blueprints/v1/tasks.py

@@ -10,6 +10,13 @@ from django.utils.text import slugify
 from django.utils.timezone import now
 from django.utils.translation import gettext_lazy as _
 from structlog.stdlib import get_logger
+from watchdog.events import (
+    FileCreatedEvent,
+    FileModifiedEvent,
+    FileSystemEvent,
+    FileSystemEventHandler,
+)
+from watchdog.observers import Observer
 from yaml import load
 from yaml.error import YAMLError
 
@@ -32,6 +39,7 @@ from authentik.lib.config import CONFIG
 from authentik.root.celery import CELERY_APP
 
 LOGGER = get_logger()
+_file_watcher_started = False
 
 
 @dataclass
@@ -45,6 +53,39 @@ class BlueprintFile:
     meta: Optional[BlueprintMetadata] = field(default=None)
 
 
+def start_blueprint_watcher():
+    """Start blueprint watcher, if it's not running already."""
+    # This function might be called twice since it's called on celery startup
+    # pylint: disable=global-statement
+    global _file_watcher_started
+    if _file_watcher_started:
+        return
+    observer = Observer()
+    observer.schedule(BlueprintEventHandler(), CONFIG.y("blueprints_dir"), recursive=True)
+    observer.start()
+    _file_watcher_started = True
+
+
+class BlueprintEventHandler(FileSystemEventHandler):
+    """Event handler for blueprint events"""
+
+    def on_any_event(self, event: FileSystemEvent):
+        if not isinstance(event, (FileCreatedEvent, FileModifiedEvent)):
+            return
+        if event.is_directory:
+            return
+        if isinstance(event, FileCreatedEvent):
+            LOGGER.debug("new blueprint file created, starting discovery")
+            blueprints_discover.delay()
+        if isinstance(event, FileModifiedEvent):
+            path = Path(event.src_path)
+            root = Path(CONFIG.y("blueprints_dir")).absolute()
+            rel_path = str(path.relative_to(root))
+            for instance in BlueprintInstance.objects.filter(path=rel_path):
+                LOGGER.debug("modified blueprint file, starting apply", instance=instance)
+                apply_blueprint.delay(instance.pk.hex)
+
+
 @CELERY_APP.task(
     throws=(DatabaseError, ProgrammingError, InternalError),
 )
@@ -60,8 +101,7 @@ def blueprints_find():
     """Find blueprints and return valid ones"""
     blueprints = []
     root = Path(CONFIG.y("blueprints_dir"))
-    for file in root.glob("**/*.yaml"):
+    for path in root.glob("**/*.yaml"):
-        path = Path(file)
         LOGGER.debug("found blueprint", path=str(path))
         with open(path, "r", encoding="utf-8") as blueprint_file:
             try:

authentik/root/celery.py

@@ -99,6 +99,9 @@ def worker_ready_hook(*args, **kwargs):
             task.delay()
         except ProgrammingError as exc:
             LOGGER.warning("Startup task failed", task=task, exc=exc)
+    from authentik.blueprints.v1.tasks import start_blueprint_watcher
+
+    start_blueprint_watcher()
 
 
 # Using a string here means the worker doesn't have to serialize

authentik/root/settings.py

@@ -436,6 +436,7 @@ _LOGGING_HANDLER_MAP = {
     "asyncio": "WARNING",
     "redis": "WARNING",
     "silk": "INFO",
+    "fsevents": "WARNING",
 }
 for handler_name, level in _LOGGING_HANDLER_MAP.items():
     # pyright: reportGeneralTypeIssues=false

pyproject.toml

@@ -155,6 +155,7 @@ webauthn = "*"
 wsproto = "*"
 xmlsec = "*"
 zxcvbn = "*"
+watchdog = "*"
 
 [tool.poetry.dev-dependencies]
 bandit = "*"

website/developer-docs/blueprints/index.md

@@ -13,6 +13,11 @@ Blueprints offer a new way to template, automate and distribute authentik config
 Blueprints are yaml files, whose format is described further in [File structure](./v1/structure). Blueprints can be applied in one of two ways:
 
 -   As a Blueprint instance, which is a YAML file mounted into the authentik (worker) container. This file is read and applied regularly (every 60 minutes). Multiple instances can be created for a single blueprint file, and instances can be given context key:value attributes to configure the blueprint.
+
+    :::info
+    Starting with authentik 2022.12.1, authentik listens for file modification/creation events in the blueprint directory and will automatically trigger a discovery when a new blueprint file is created, and trigger a blueprint apply when a file is modified.
+    :::
+
 -   As a Flow import, which is a YAML file uploaded via the Browser/API. This file is validated and applied directly after being uploaded, but is not further monitored/applied.
 
 Starting with authentik 2022.8, blueprints are used to manage authentik default flows and other system objects. These blueprints can be disabled/replaced with custom blueprints in certain circumstances.