main.ts

/*
 * main.ts
 *
 * Utilities for main() functions (setup, cleanup, etc)
 *
 * Copyright (C) 2022 Posit Software, PBC
 */

import { initializeLogger, logError, logOptions } from "./log.ts";
import { Args } from "flags";
import { parse } from "flags";
import { exitWithCleanup } from "./cleanup.ts";
import {
  captureFileReads,
  type MetricsKeys,
  reportPerformanceMetrics,
} from "./performance/metrics.ts";
import { makeTimedFunctionAsync } from "./performance/function-times.ts";
import { isWindows } from "../deno_ral/platform.ts";
import { convertCombinedLuaProfileToCSV } from "./performance/perfetto-utils.ts";
import { info } from "../deno_ral/log.ts";

type Runner = (args: Args) => Promise<unknown>;
export async function mainRunner(runner: Runner) {
  try {
    // Parse the raw args to read globals and initialize logging
    const args = parse(Deno.args);
    await initializeLogger(logOptions(args));

    // install termination signal handlers

    // Even though windows doesn't technically have signals, Deno
    // does the "expected" thing here and calls abend
    // on interruption.
    Deno.addSignalListener("SIGINT", abend);
    if (!isWindows) {
      Deno.addSignalListener("SIGTERM", abend);
    }

    const metricEnv = Deno.env.get("QUARTO_REPORT_PERFORMANCE_METRICS");
    if (metricEnv === "true" || metricEnv?.split(",").includes("fileReads")) {
      captureFileReads();
    }

    const main = makeTimedFunctionAsync("main", async () => {
      return await runner(args);
    });
    await main();

    // if profiling, wait for 10 seconds before quitting
    if (Deno.env.get("QUARTO_TS_PROFILE") !== undefined) {
      info("Program finished. Turn off the Chrome profiler now!");
      info("Waiting for 10 seconds ...");
      await new Promise((resolve) => setTimeout(resolve, 10000));
    }

    const combinedLuaProfile = Deno.env.get("QUARTO_COMBINED_LUA_PROFILE");
    if (combinedLuaProfile) {
      convertCombinedLuaProfileToCSV(combinedLuaProfile);
    }

    if (metricEnv !== undefined) {
      if (metricEnv !== "true") {
        reportPerformanceMetrics(metricEnv.split(",") as MetricsKeys[]);
      } else {
        reportPerformanceMetrics();
      }
    }

    exitWithCleanup(0);
  } catch (e) {
    if (e) {
      logError(e);
    }
  } finally {
    abend();
  }
}

function abend() {
  exitWithCleanup(1);
}