feat: pass context to feed post-processors (#43)

Post-processors now receive Context as their 2nd parameter,
allowing them to use contextual data (time, location, etc.)
when producing enhancements.

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

packages/aris-core/src/feed-engine.ts

@@ -177,7 +177,7 @@ export class FeedEngine<TItems extends FeedItem = FeedItem> {
 			items: processedItems,
 			groupedItems,
 			errors: postProcessorErrors,
-		} = await this.applyPostProcessors(items as TItems[], errors)
+		} = await this.applyPostProcessors(items as TItems[], context, errors)
 
 		const result: FeedResult<TItems> = {
 			context,
@@ -294,6 +294,7 @@ export class FeedEngine<TItems extends FeedItem = FeedItem> {
 
 	private async applyPostProcessors(
 		items: TItems[],
+		context: Context,
 		errors: SourceError[],
 	): Promise<{ items: TItems[]; groupedItems: ItemGroup[]; errors: SourceError[] }> {
 		let currentItems = items
@@ -303,7 +304,7 @@ export class FeedEngine<TItems extends FeedItem = FeedItem> {
 		for (const processor of this.postProcessors) {
 			const snapshot = currentItems
 			try {
-				const enhancement = await processor(currentItems)
+				const enhancement = await processor(currentItems, context)
 
 				if (enhancement.additionalItems?.length) {
 					// Post-processors operate on FeedItem[] without knowledge of TItems.
@@ -399,7 +400,7 @@ export class FeedEngine<TItems extends FeedItem = FeedItem> {
 			items: processedItems,
 			groupedItems,
 			errors: postProcessorErrors,
-		} = await this.applyPostProcessors(items as TItems[], errors)
+		} = await this.applyPostProcessors(items as TItems[], this.context, errors)
 
 		const result: FeedResult<TItems> = {
 			context: this.context,

packages/aris-core/src/feed-post-processor.test.ts

@@ -333,9 +333,7 @@ describe("FeedPostProcessor", () => {
 				},
 			}
 
-			const engine = new FeedEngine()
-				.register(source)
-				.registerPostProcessor(async () => {
+			const engine = new FeedEngine().register(source).registerPostProcessor(async () => {
 				callCount++
 				return {}
 			})
@@ -377,9 +375,7 @@ describe("FeedPostProcessor", () => {
 				},
 			}
 
-			const engine = new FeedEngine()
-				.register(source)
-				.registerPostProcessor(async () => {
+			const engine = new FeedEngine().register(source).registerPostProcessor(async () => {
 				callCount++
 				return {}
 			})

packages/aris-core/src/feed-post-processor.ts

@@ -1,3 +1,4 @@
+import type { Context } from "./context"
 import type { FeedItem } from "./feed"
 
 export interface ItemGroup {
@@ -20,4 +21,4 @@ export interface FeedEnhancement {
  * A function that transforms feed items and produces enhancement directives.
  * Use named functions for meaningful error attribution.
  */
-export type FeedPostProcessor = (items: FeedItem[]) => Promise<FeedEnhancement>
+export type FeedPostProcessor = (items: FeedItem[], context: Context) => Promise<FeedEnhancement>