Added/deleted-type websocket messages

Events are now sent for not only when an object changes but also when one is created or deleted.

For now it's not really possible to subscribe to these events however.

This breaks backwards-compatibility with the websocket messages.

pyproject.toml

@@ -58,6 +58,7 @@ ignore = [
     "D406",
     "D407",
     "FA100",
+    "FIX002",
     "S104",
     "TRY201",
     "TRY003",
@@ -66,6 +67,8 @@ ignore = [
     "DTZ003",
     "PLR0913",
     "SIM108",
+    "TD002",
+    "TD003",
 ]
 line-length = 120
 target-version = "py39"

spoolman/api/v1/models.py

@@ -1,6 +1,7 @@
 """Pydantic data models for typing the FastAPI request/responses."""
 
 from datetime import datetime, timezone
+from enum import Enum
 from typing import Optional
 
 from pydantic import BaseModel as PydanticBaseModel
@@ -228,3 +229,37 @@ class BackupResponse(BaseModel):
         description="Path to the created backup file.",
         example="/home/app/.local/share/spoolman/backups/spoolman.db",
     )
+
+
+class EventType(str, Enum):
+    """Event types."""
+
+    ADDED = "added"
+    UPDATED = "updated"
+    DELETED = "deleted"
+
+
+class Event(BaseModel):
+    """Event."""
+
+    type: EventType = Field(description="Event type.")
+    date: datetime = Field(description="When the event occured. UTC Timezone.")
+    payload: BaseModel
+
+
+class SpoolEvent(Event):
+    """Event."""
+
+    payload: Spool = Field(description="Updated spool.")
+
+
+class FilamentEvent(Event):
+    """Event."""
+
+    payload: Filament = Field(description="Updated filament.")
+
+
+class VendorEvent(Event):
+    """Event."""
+
+    payload: Vendor = Field(description="Updated vendor.")

spoolman/database/filament.py

@@ -10,7 +10,7 @@ from sqlalchemy.exc import IntegrityError
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm import contains_eager, joinedload
 
-from spoolman.api.v1.models import Filament
+from spoolman.api.v1.models import EventType, Filament, FilamentEvent
 from spoolman.database import models, vendor
 from spoolman.database.utils import (
     SortOrder,
@@ -45,7 +45,7 @@ async def create(
     if vendor_id is not None:
         vendor_item = await vendor.get_by_id(db, vendor_id)
 
-    db_item = models.Filament(
+    filament = models.Filament(
         name=name,
         registered=datetime.utcnow().replace(microsecond=0),
         vendor=vendor_item,
@@ -61,9 +61,10 @@ async def create(
         settings_bed_temp=settings_bed_temp,
         color_hex=color_hex,
     )
-    db.add(db_item)
+    db.add(filament)
     await db.commit()
-    return db_item
+    await filament_changed(filament, EventType.ADDED)
+    return filament
 
 
 async def get_by_id(db: AsyncSession, filament_id: int) -> models.Filament:
@@ -150,7 +151,7 @@ async def update(
         else:
             setattr(filament, k, v)
     await db.commit()
-    await filament_changed(filament)
+    await filament_changed(filament, EventType.UPDATED)
     return filament
 
 
@@ -160,6 +161,7 @@ async def delete(db: AsyncSession, filament_id: int) -> None:
     await db.delete(filament)
     try:
         await db.commit()  # Flush immediately so any errors are propagated in this request.
+        await filament_changed(filament, EventType.DELETED)
     except IntegrityError as exc:
         await db.rollback()
         raise ItemDeleteError("Failed to delete filament.") from exc
@@ -188,6 +190,13 @@ async def find_article_numbers(
     return [row[0] for row in rows.all() if row[0] is not None]
 
 
-async def filament_changed(filament: models.Filament) -> None:
+async def filament_changed(filament: models.Filament, typ: EventType) -> None:
     """Notify websocket clients that a filament has changed."""
-    await websocket_manager.send(("filament", str(filament.id)), Filament.from_db(filament).json())
+    await websocket_manager.send(
+        ("filament", str(filament.id)),
+        FilamentEvent(
+            type=typ,
+            date=datetime.utcnow(),
+            payload=Filament.from_db(filament),
+        ),
+    )

spoolman/database/spool.py

@@ -10,7 +10,7 @@ from sqlalchemy.exc import NoResultFound
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm import contains_eager, joinedload
 
-from spoolman.api.v1.models import Spool
+from spoolman.api.v1.models import EventType, Spool, SpoolEvent
 from spoolman.database import filament, models
 from spoolman.database.utils import (
     SortOrder,
@@ -59,7 +59,7 @@ async def create(
     if last_used is not None:
         last_used = utc_timezone_naive(last_used)
 
-    db_item = models.Spool(
+    spool = models.Spool(
         filament=filament_item,
         registered=datetime.utcnow().replace(microsecond=0),
         used_weight=used_weight,
@@ -70,9 +70,10 @@ async def create(
         comment=comment,
         archived=archived,
     )
-    db.add(db_item)
+    db.add(spool)
     await db.commit()
-    return db_item
+    await spool_changed(spool, EventType.ADDED)
+    return spool
 
 
 async def get_by_id(db: AsyncSession, spool_id: int) -> models.Spool:
@@ -182,7 +183,7 @@ async def update(
         else:
             setattr(spool, k, v)
     await db.commit()
-    await spool_changed(spool)
+    await spool_changed(spool, EventType.UPDATED)
     return spool
 
 
@@ -190,6 +191,7 @@ async def delete(db: AsyncSession, spool_id: int) -> None:
     """Delete a spool object."""
     spool = await get_by_id(db, spool_id)
     await db.delete(spool)
+    await spool_changed(spool, EventType.DELETED)
 
 
 async def use_weight_safe(db: AsyncSession, spool_id: int, weight: float) -> None:
@@ -235,7 +237,7 @@ async def use_weight(db: AsyncSession, spool_id: int, weight: float) -> models.S
     spool.last_used = datetime.utcnow().replace(microsecond=0)
 
     await db.commit()
-    await spool_changed(spool)
+    await spool_changed(spool, EventType.UPDATED)
     return spool
 
 
@@ -280,7 +282,7 @@ async def use_length(db: AsyncSession, spool_id: int, length: float) -> models.S
     spool.last_used = datetime.utcnow().replace(microsecond=0)
 
     await db.commit()
-    await spool_changed(spool)
+    await spool_changed(spool, EventType.UPDATED)
     return spool
 
 
@@ -304,6 +306,13 @@ async def find_lot_numbers(
     return [row[0] for row in rows.all() if row[0] is not None]
 
 
-async def spool_changed(spool: models.Spool) -> None:
+async def spool_changed(spool: models.Spool, typ: EventType) -> None:
     """Notify websocket clients that a spool has changed."""
-    await websocket_manager.send(("spool", str(spool.id)), Spool.from_db(spool).json())
+    await websocket_manager.send(
+        ("spool", str(spool.id)),
+        SpoolEvent(
+            type=typ,
+            date=datetime.utcnow(),
+            payload=Spool.from_db(spool),
+        ),
+    )

spoolman/database/vendor.py

@@ -6,7 +6,7 @@ from typing import Optional
 from sqlalchemy import func, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from spoolman.api.v1.models import Vendor
+from spoolman.api.v1.models import EventType, Vendor, VendorEvent
 from spoolman.database import models
 from spoolman.database.utils import SortOrder, add_where_clause_str
 from spoolman.exceptions import ItemNotFoundError
@@ -20,14 +20,15 @@ async def create(
     comment: Optional[str] = None,
 ) -> models.Vendor:
     """Add a new vendor to the database."""
-    db_item = models.Vendor(
+    vendor = models.Vendor(
         name=name,
         registered=datetime.utcnow().replace(microsecond=0),
         comment=comment,
     )
-    db.add(db_item)
+    db.add(vendor)
     await db.commit()
-    return db_item
+    await vendor_changed(vendor, EventType.ADDED)
+    return vendor
 
 
 async def get_by_id(db: AsyncSession, vendor_id: int) -> models.Vendor:
@@ -89,7 +90,7 @@ async def update(
     for k, v in data.items():
         setattr(vendor, k, v)
     await db.commit()
-    await vendor_changed(vendor)
+    await vendor_changed(vendor, EventType.UPDATED)
     return vendor
 
 
@@ -97,8 +98,16 @@ async def delete(db: AsyncSession, vendor_id: int) -> None:
     """Delete a vendor object."""
     vendor = await get_by_id(db, vendor_id)
     await db.delete(vendor)
+    await vendor_changed(vendor, EventType.DELETED)
 
 
-async def vendor_changed(vendor: models.Vendor) -> None:
+async def vendor_changed(vendor: models.Vendor, typ: EventType) -> None:
     """Notify websocket clients that a vendor has changed."""
-    await websocket_manager.send(("vendor", str(vendor.id)), Vendor.from_db(vendor).json())
+    await websocket_manager.send(
+        ("vendor", str(vendor.id)),
+        VendorEvent(
+            type=typ,
+            date=datetime.utcnow(),
+            payload=Vendor.from_db(vendor),
+        ),
+    )

spoolman/ws.py

@@ -4,6 +4,8 @@ import logging
 
 from fastapi import WebSocket
 
+from spoolman.api.v1.models import Event
+
 logger = logging.getLogger(__name__)
 
 
@@ -37,12 +39,12 @@ class WebsocketManager:
             pool_str,
         )
 
-    async def send(self, pool: tuple[str, ...], message: str) -> None:
+    async def send(self, pool: tuple[str, ...], evt: Event) -> None:
         """Send a message to all websockets in a pool."""
         pool_str = ",".join(pool)
         if pool_str in self.connections:
             for websocket in self.connections[pool_str]:
-                await websocket.send_text(message)
+                await websocket.send_text(evt.json())
 
 
 websocket_manager = WebsocketManager()