refactor: consolidate backend services

Replace per-source services (LocationService, WeatherService,
TflService, FeedEngineService) with a single UserSessionManager
that owns all per-user state. Source creation is delegated to
thin FeedSourceProvider implementations per source type.

Co-authored-by: Ona <no-reply@ona.com>

apps/aris-backend/src/location/router.ts

@@ -1,10 +1,7 @@
-import { TRPCError } from "@trpc/server"
 import { type } from "arktype"
 
+import type { UserSessionManager } from "../session/index.ts"
 import type { TRPC } from "../trpc/router.ts"
-import type { LocationService } from "./service.ts"
-
-import { UserNotFoundError } from "../lib/error.ts"
 
 const locationInput = type({
 	lat: "number",
@@ -15,23 +12,17 @@ const locationInput = type({
 
 export function createLocationRouter(
 	t: TRPC,
-	{ locationService }: { locationService: LocationService },
+	{ sessionManager }: { sessionManager: UserSessionManager },
 ) {
 	return t.router({
-		update: t.procedure.input(locationInput).mutation(({ input, ctx }) => {
-			try {
-				locationService.updateUserLocation(ctx.user.id, {
-					lat: input.lat,
-					lng: input.lng,
-					accuracy: input.accuracy,
-					timestamp: input.timestamp,
-				})
-			} catch (error) {
-				if (error instanceof UserNotFoundError) {
-					throw new TRPCError({ code: "NOT_FOUND", message: error.message })
-				}
-				throw error
-			}
+		update: t.procedure.input(locationInput).mutation(async ({ input, ctx }) => {
+			const session = sessionManager.getOrCreate(ctx.user.id)
+			await session.engine.executeAction("aris.location", "update-location", {
+				lat: input.lat,
+				lng: input.lng,
+				accuracy: input.accuracy,
+				timestamp: input.timestamp,
+			})
 		}),
 	})
 }

apps/aris-backend/src/location/service.test.ts

@@ -1,111 +0,0 @@
-import { describe, expect, test } from "bun:test"
-
-import { UserNotFoundError } from "../lib/error.ts"
-import { LocationService } from "./service.ts"
-
-describe("LocationService", () => {
-	test("feedSourceForUser creates source on first call", () => {
-		const service = new LocationService()
-		const source = service.feedSourceForUser("user-1")
-
-		expect(source).toBeDefined()
-		expect(source.id).toBe("aris.location")
-	})
-
-	test("feedSourceForUser returns same source for same user", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-		const source2 = service.feedSourceForUser("user-1")
-
-		expect(source1).toBe(source2)
-	})
-
-	test("feedSourceForUser returns different sources for different users", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-		const source2 = service.feedSourceForUser("user-2")
-
-		expect(source1).not.toBe(source2)
-	})
-
-	test("updateUserLocation updates the source", () => {
-		const service = new LocationService()
-		const source = service.feedSourceForUser("user-1")
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location)
-
-		expect(source.lastLocation).toEqual(location)
-	})
-
-	test("updateUserLocation throws if source does not exist", () => {
-		const service = new LocationService()
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		expect(() => service.updateUserLocation("user-1", location)).toThrow(UserNotFoundError)
-	})
-
-	test("lastUserLocation returns null for unknown user", () => {
-		const service = new LocationService()
-
-		expect(service.lastUserLocation("unknown")).toBeNull()
-	})
-
-	test("lastUserLocation returns last location", () => {
-		const service = new LocationService()
-		service.feedSourceForUser("user-1")
-		const location1 = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-		const location2 = {
-			lat: 52.0,
-			lng: -0.2,
-			accuracy: 5,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location1)
-		service.updateUserLocation("user-1", location2)
-
-		expect(service.lastUserLocation("user-1")).toEqual(location2)
-	})
-
-	test("removeUser removes the source", () => {
-		const service = new LocationService()
-		service.feedSourceForUser("user-1")
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location)
-		service.removeUser("user-1")
-
-		expect(service.lastUserLocation("user-1")).toBeNull()
-	})
-
-	test("removeUser allows new source to be created", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-
-		service.removeUser("user-1")
-		const source2 = service.feedSourceForUser("user-1")
-
-		expect(source1).not.toBe(source2)
-	})
-})

apps/aris-backend/src/location/service.ts

@@ -1,57 +0,0 @@
-import { LocationSource, type Location } from "@aris/source-location"
-
-import type { FeedSourceProvider } from "../feed/service.ts"
-
-import { UserNotFoundError } from "../lib/error.ts"
-
-/**
- * Manages LocationSource instances per user.
- */
-export class LocationService implements FeedSourceProvider {
-	private sources = new Map<string, LocationSource>()
-
-	/**
-	 * Get or create a LocationSource for a user.
-	 * @param userId - The user's unique identifier
-	 * @returns The user's LocationSource instance
-	 */
-	feedSourceForUser(userId: string): LocationSource {
-		let source = this.sources.get(userId)
-		if (!source) {
-			source = new LocationSource()
-			this.sources.set(userId, source)
-		}
-		return source
-	}
-
-	/**
-	 * Update location for a user.
-	 * @param userId - The user's unique identifier
-	 * @param location - The new location data
-	 * @throws {UserNotFoundError} If no source exists for the user
-	 */
-	updateUserLocation(userId: string, location: Location): void {
-		const source = this.sources.get(userId)
-		if (!source) {
-			throw new UserNotFoundError(userId)
-		}
-		source.pushLocation(location)
-	}
-
-	/**
-	 * Get last known location for a user.
-	 * @param userId - The user's unique identifier
-	 * @returns The last location, or null if none exists
-	 */
-	lastUserLocation(userId: string): Location | null {
-		return this.sources.get(userId)?.lastLocation ?? null
-	}
-
-	/**
-	 * Remove a user's LocationSource.
-	 * @param userId - The user's unique identifier
-	 */
-	removeUser(userId: string): void {
-		this.sources.delete(userId)
-	}
-}