uptime-monitoring/src/worker/scheduled/rollup.ts

import { and, eq, gte, lt, sql } from 'drizzle-orm';
import { getDb } from '../db/client';
import { checks, monitorDailyStats } from '../db/schema';

export type DailyRollupSummary = {
	day: string;
	monitors: number;
};

export async function runDailyRollup(env: Env, now = new Date()): Promise<DailyRollupSummary> {
	const db = getDb(env);
	const currentUtcDay = Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate());
	const dayStart = new Date(currentUtcDay - 24 * 60 * 60 * 1000);
	const dayEnd = new Date(currentUtcDay);

	const rows = await db
		.select({
			monitorId: checks.monitorId,
			totalChecks: sql<number>`count(*)`,
			upChecks: sql<number>`sum(case when ${checks.ok} = 1 then 1 else 0 end)`,
			avgLatencyMs: sql<number | null>`round(avg(${checks.latencyMs}))`,
			minLatencyMs: sql<number | null>`min(${checks.latencyMs})`,
			maxLatencyMs: sql<number | null>`max(${checks.latencyMs})`,
		})
		.from(checks)
		.where(and(gte(checks.checkedAt, dayStart), lt(checks.checkedAt, dayEnd), eq(checks.maintenance, false)))
		.groupBy(checks.monitorId);

	if (rows.length > 0) {
		const statements = rows.map((row) =>
			db
				.insert(monitorDailyStats)
				.values({
					monitorId: row.monitorId,
					day: dayStart,
					totalChecks: row.totalChecks,
					upChecks: row.upChecks,
					avgLatencyMs: row.avgLatencyMs,
					minLatencyMs: row.minLatencyMs,
					maxLatencyMs: row.maxLatencyMs,
				})
				.onConflictDoUpdate({
					target: [monitorDailyStats.monitorId, monitorDailyStats.day],
					set: {
						totalChecks: row.totalChecks,
						upChecks: row.upChecks,
						avgLatencyMs: row.avgLatencyMs,
						minLatencyMs: row.minLatencyMs,
						maxLatencyMs: row.maxLatencyMs,
					},
				}),
		);
		await db.batch(statements as [(typeof statements)[number], ...typeof statements]);
	}

	return { day: dayStart.toISOString().slice(0, 10), monitors: rows.length };
}