beatsaber-metrics-tracker/src/services/api.ts

import express from "express";
import { INFLUXDB_BUCKET, InfluxQueryAPI } from "../index";
import { formatString } from "../utils/stringUtils";

const app = express();
const port = process.env.PORT || 3000;

// Query to get the player count history for tge last 24 hours in 1 hour intervals
const getPlayerHistoryQuery = `from(bucket: "${INFLUXDB_BUCKET}")
  |> range(start: {})
  |> filter(fn: (r) => r["_measurement"] == "scoresaber")
  |> filter(fn: (r) => r["_field"] == "value")
  |> filter(fn: (r) => r["type"] == "player_count")
  |> aggregateWindow(every: 1h, fn: mean)
  |> yield()
`;

app.get("/", (req, res) => {
  res.send("Hello!");
});

app.get("/analytics", async (req, res) => {
  const before = new Date().getTime();

  const timeQuery = req.query.time || "24h";
  const timeInMs = parseTimeToMilliseconds(timeQuery.toString());
  if (timeInMs > 30 * 24 * 60 * 60 * 1000) {
    return res.status(400).json({
      error: "Time range too large. Max time range is 30 days.",
    });
  }

  const rows = await InfluxQueryAPI.collectRows(
    formatString(getPlayerHistoryQuery, false, timeQuery)
  );
  let history = rows.map((row: any) => ({
    time: row._time,
    value: row._value !== null ? row._value.toFixed(0) : null,
  }));
  history = history.sort(
    (a: any, b: any) => new Date(a.time).getTime() - new Date(b.time).getTime()
  );

  return res.json({
    serverTimeTaken: new Date().getTime() - before + "ms",
    history: history,
  });
});

app.listen(port, () => {
  console.log(`API Server is running on http://localhost:${port}`);
});