Event bus basics

app/api/v1.py

@@ -1,4 +1,4 @@
-from automapper import mapper
+from automapper import mapper, exceptions
 from fastapi import APIRouter, Depends
 from fastapi_utils.cbv import cbv
 from starlette.responses import JSONResponse, Response
@@ -6,6 +6,7 @@ from starlette.responses import JSONResponse, Response
 from app.api.models import Request
 from app.core.core import WebhookProcessor
 from app.core.injects import AutowireSupport
+from app.events import SimpleEventBus
 from app.model.webhook import WebhookEvent
 
 router = APIRouter()
@@ -19,16 +20,21 @@ async def root():
 @cbv(router)
 class APIv1:
   webhook_service: WebhookProcessor = Depends(AutowireSupport.webhook_processor)
+  event_bus: SimpleEventBus = Depends(AutowireSupport.event_bus)
   logger = __import__('logging').getLogger(__name__)
 
   def __init__(self):
-    mapper.add(Request, WebhookEvent)
+    try: # TODO: rejestracja w innym miejscu: klasa jest przeładowywana co żądanie
+      mapper.add(Request, WebhookEvent)
+    except exceptions.DuplicatedRegistrationError:
+      pass
 
   @router.get("/health", summary="Health check")
   async def health(self) -> JSONResponse:
-    return JSONResponse({"status": self.webhook_service.health})
+    # TODO: JSON serialize
+    return JSONResponse({"status": self.webhook_service.health.healthy})
 
   @router.post("/ci", summary="CI Webhook")
   async def ci(self, request: Request):
-    self.webhook_service.enqueue(mapper.map(request))
+    self.event_bus.publish(mapper.map(request))
     return Response(status_code=201)

app/core/core.py

@@ -3,6 +3,7 @@ import uuid
 from typing import Annotated, List
 
 from injectable import injectable, autowired, Autowired
+from typing_extensions import deprecated
 
 from app.core.queue import EnqueuedProcessor, ProcessQueue, Task, Result
 from app.model.healthcheck import HealthCheck
@@ -11,20 +12,19 @@ from app.services import DockerService, GitService, Passwords
 
 logger = logging.getLogger(__name__)
 
+@deprecated("Use event bus instead.")
 @injectable(singleton=True)
-class WebhookProcessor(EnqueuedProcessor):
+class WebhookProcessor:
     @autowired
     def __init__(self, docker: Annotated[DockerService, Autowired],
                  git: Annotated[GitService, Autowired],
-                 keepass: Annotated[Passwords, Autowired],
+                 keepass: Annotated[Passwords, Autowired]):
-                 queue: Annotated[ProcessQueue, Autowired]):
-      super().__init__(queue)
       self._docker = docker
       self._git = git
       self._keepass = keepass
 
     def enqueue(self, event: WebhookEvent):
-      self._enqueue(Task(uuid.UUID(), self, event))
+      pass
 
     def _process(self, task: Task[WebhookEvent]) -> Result:
       event: WebhookEvent = task.payload

app/core/injects.py

@@ -1,6 +1,7 @@
 from injectable import inject
 
 from app.core.core import WebhookProcessor
+from app.events import SimpleEventBus
 
 
 class AutowireSupport:
@@ -8,3 +9,7 @@ class AutowireSupport:
   @staticmethod
   def webhook_processor():
     return inject(WebhookProcessor)
+
+  @staticmethod
+  def event_bus():
+    return inject(SimpleEventBus)

app/core/woodpecker.py

@@ -0,0 +1,22 @@
+import logging
+
+from injectable import injectable
+
+from app.events import SimpleEventBus
+from app.model.webhook import WebhookEvent
+
+logger = logging.getLogger(__name__)
+
+@injectable
+class Woodpecker:
+
+  @SimpleEventBus.on(WebhookEvent)
+  def on_event(self, event): # TODO: caller nie działa -> brakuje instancji klasy?
+    logger.info(f"Received event: {event}")
+    pass
+
+
+@SimpleEventBus.on(WebhookEvent)
+def on_event2(event): # TODO: Tu działa
+  logger.info(f"F2: Received event: {event}")
+  pass

app/events/__init__.py

@@ -0,0 +1,41 @@
+from concurrent.futures import ThreadPoolExecutor
+from dataclasses import dataclass
+from functools import wraps
+from typing import Dict, List, Callable
+
+from injectable import injectable, inject
+
+
+@dataclass
+class Event:
+  pass
+
+
+@injectable(singleton=True)
+class SimpleEventBus:
+  def __init__(self):
+    self._handlers: Dict[type, List[Callable]] = {}
+    self._executor = ThreadPoolExecutor()
+
+  def publish(self, event: Event) -> None:
+      for handler in self._handlers.get(type(event), []):
+        # Fire-and-forget execution
+        self._executor.submit(handler, event)
+
+  def subscribe(self, event_type: type, handler: Callable) -> None:
+    if event_type not in self._handlers:
+      self._handlers[event_type] = []
+    self._handlers[event_type].append(handler)
+
+  @staticmethod
+  def on(event: type) -> Callable:
+    def outer(func):
+      inject(SimpleEventBus).subscribe(event, func)
+
+      @wraps(func)
+      def wrapper(*args, **kwargs):
+        return func(*args, **kwargs)
+
+      return wrapper
+
+    return outer

app/main.py

@@ -11,11 +11,11 @@ class KarlApplication:
   from starlette.types import Receive, Scope, Send
   def __init__(self) -> None:
     self._set_logging()
+    load_injection_container()
     _app = FastAPI(title="Karl", version="0.1.0")
     self._set_middlewares(_app)
     self._set_routes(_app)
     self._set_events(_app)
-    self._init_services()
 
     self._app = _app
 
@@ -58,10 +58,6 @@ class KarlApplication:
   def _set_events(self, app: FastAPI):
     pass
 
-  def _init_services(self):
-    logger = logging.getLogger(__name__)
-    load_injection_container()
-
 
 def run():
   return KarlApplication()

app/model/webhook.py

@@ -1,9 +1,11 @@
 from dataclasses import dataclass
 from typing import List
 
+from app.events import Event
+
 
 @dataclass
-class WebhookEvent:
+class WebhookEvent(Event):
   _id: str
   commit: str
   message: str

app/services/passwords.py

@@ -11,7 +11,7 @@ class Passwords:
     settings = get_settings()
 
     with open(settings.kp.secret, "r") as fh:
-      secret = fh.read()
+      secret = fh.read().splitlines()[0]
 
     self._kp_org = self.__get_or_create_store(settings.kp.file, secret)
     self._kp = self.__get_lock(settings.kp.file, secret)