astro/dist/cli/dev/logs.js

Astro is a modern site builder with web best practices, performance, and DX front-of-mind.

import { readFileSync, existsSync, statSync, createReadStream, watch } from "node:fs";
import { fileURLToPath, pathToFileURL } from "node:url";
import { checkExistingServer, getLogFileURL, isProcessAlive } from "../../core/dev/lockfile.js";
import { resolveRoot } from "../../core/config/config.js";
async function logs({
  flags,
  logger
}) {
  const root = pathToFileURL(resolveRoot(flags.root) + "/");
  const existing = checkExistingServer(root);
  if (!existing) {
    logger.error("SKIP_FORMAT", "No dev server is running.");
    process.exit(1);
  }
  if (!existing.background) {
    logger.error(
      "SKIP_FORMAT",
      "The running dev server was not started with `astro dev --background`. View logs in the terminal where it was started."
    );
    process.exit(1);
  }
  const logFileURL = getLogFileURL(root);
  const logFilePath = fileURLToPath(logFileURL);
  if (!existsSync(logFilePath)) {
    logger.error("SKIP_FORMAT", "No log file found.");
    process.exit(1);
  }
  const follow = flags.follow || flags.f;
  if (!follow) {
    const content = readFileSync(logFilePath, "utf-8");
    process.stdout.write(content);
    return;
  }
  let offset = statSync(logFilePath).size;
  if (offset > 0) {
    const content = readFileSync(logFilePath, "utf-8");
    process.stdout.write(content);
  }
  const watcher = watch(logFilePath, () => {
    const currentSize = statSync(logFilePath).size;
    if (currentSize > offset) {
      const stream = createReadStream(logFilePath, { start: offset, encoding: "utf-8" });
      stream.on("data", (chunk) => process.stdout.write(chunk));
      stream.on("end", () => {
        offset = currentSize;
      });
    }
  });
  const aliveCheck = setInterval(() => {
    if (!isProcessAlive(existing.pid)) {
      const currentSize = statSync(logFilePath).size;
      if (currentSize > offset) {
        const remaining = readFileSync(logFilePath, { encoding: "utf-8" }).slice(offset);
        process.stdout.write(remaining);
      }
      watcher.close();
      clearInterval(aliveCheck);
    }
  }, 1e3);
  const cleanup = () => {
    watcher.close();
    clearInterval(aliveCheck);
    process.exit(0);
  };
  process.on("SIGINT", cleanup);
  process.on("SIGTERM", cleanup);
  await new Promise(() => {
  });
}
export {
  logs
};