refactor: events to a pure stream instead of being part of topics

NOTE: tests are passing, but the client is broken

public/api/channels/:channel_id/events/index.ts

@@ -0,0 +1,134 @@
+import { get_session, get_user, PRECHECK_TABLE, require_user } from '../../../../../utils/prechecks.ts';
+import { CHANNEL, CHANNELS } from '../../../../../models/channel.ts';
+import * as CANNED_RESPONSES from '../../../../../utils/canned_responses.ts';
+import { EVENT, EVENTS } from '../../../../../models/event.ts';
+import { FSDB_SEARCH_OPTIONS, WALK_ENTRY } from '@andyburke/fsdb';
+
+export const PRECHECKS: PRECHECK_TABLE = {};
+
+// GET /api/channels/:channel_id/events - get channel events
+// query parameters:
+//   partial_id: the partial id subset you would like to match (remember, lurids are lexigraphically sorted)
+PRECHECKS.GET = [get_session, get_user, require_user, async (_req: Request, meta: Record<string, any>): Promise<Response | undefined> => {
+	const channel_id: string = meta.params?.channel_id?.toLowerCase().trim() ?? '';
+
+	// lurid is 49 chars as we use them, eg: "also-play-flow-want-form-wide-thus-work-burn-same"
+	const channel: CHANNEL | null = channel_id.length === 49 ? await CHANNELS.get(channel_id) : null;
+
+	if (!channel) {
+		return CANNED_RESPONSES.not_found();
+	}
+
+	meta.channel = channel;
+
+	const channel_is_public: boolean = meta.channel.permissions.read.length === 0;
+	const user_has_read_for_channel = channel_is_public || meta.channel.permissions.read.includes(meta.user.id);
+
+	if (!user_has_read_for_channel) {
+		return CANNED_RESPONSES.permission_denied();
+	}
+}];
+export async function GET(request: Request, meta: Record<string, any>): Promise<Response> {
+	const sorts = EVENTS.sorts;
+	const sort_name: string = meta.query.sort ?? 'newest';
+	const key = sort_name as keyof typeof sorts;
+	const sort: any = sorts[key];
+	if (!sort) {
+		return Response.json({
+			error: {
+				message: 'You must specify a sort: newest, oldest, latest, stalest',
+				cause: 'invalid_sort'
+			}
+		}, {
+			status: 400
+		});
+	}
+
+	const options: FSDB_SEARCH_OPTIONS<EVENT> = {
+		...(meta.query ?? {}),
+		limit: Math.min(parseInt(meta.query?.limit ?? '10', 10), 1_000),
+		offset: Math.max(parseInt(meta.query?.offset ?? '0', 10), 0),
+		sort,
+		filter: (entry: WALK_ENTRY<EVENT>) => {
+			const {
+				event_type,
+				event_id
+			} = /^.*\/(?<event_type>.*?):(?<event_id>[A-Za-z-]+)\.json$/.exec(entry.path)?.groups ?? {};
+
+			if (meta.query.after_id && event_id <= meta.query.after_id) {
+				return false;
+			}
+
+			if (meta.query.before_id && event_id >= meta.query.before_id) {
+				return false;
+			}
+
+			if (meta.query.type && !meta.query.type.split(',').includes(event_type)) {
+				return false;
+			}
+
+			return true;
+		}
+	};
+
+	const headers = {
+		'Cache-Control': 'no-cache, must-revalidate'
+	};
+
+	const results = (await EVENTS.find({
+		channel: meta.channel.id
+	}, options))
+		.map((entry: WALK_ENTRY<EVENT>) => entry.load())
+		.sort((lhs_item: EVENT, rhs_item: EVENT) => rhs_item.timestamps.created.localeCompare(lhs_item.timestamps.created));
+
+	// long-polling support
+	if (results.length === 0 && meta.query.wait) {
+		return new Promise((resolve, reject) => {
+			function on_create(create_event: any) {
+				if (create_event.item.channel !== meta.channel.id) {
+					return;
+				}
+
+				if (meta.query.type && !meta.query.type.split(',').includes(create_event.item.type)) {
+					return;
+				}
+
+				results.push(create_event.item);
+				clearTimeout(timeout);
+				EVENTS.off('create', on_create);
+
+				return resolve(Response.json(results, {
+					status: 200,
+					headers
+				}));
+			}
+
+			const timeout = setTimeout(() => {
+				EVENTS.off('create', on_create);
+				return resolve(Response.json(results, {
+					status: 200,
+					headers
+				}));
+			}, 60_000); // 60 seconds
+			EVENTS.on('create', on_create);
+			request.signal.addEventListener('abort', () => {
+				EVENTS.off('create', on_create);
+				clearTimeout(timeout);
+				reject(new Error('request aborted'));
+			});
+			Deno.addSignalListener('SIGINT', () => {
+				EVENTS.off('create', on_create);
+				clearTimeout(timeout);
+				return resolve(Response.json(results, {
+					status: 200,
+					headers
+				}));
+			});
+		});
+	}
+
+	return Response.json(results, {
+		status: 200,
+		headers
+	});
+}