Function readSessionHeader

lib/session-reader.ts:156–187

(filePath: string)

}

export function readSessionHeader(filePath: string): SessionHeader | null {
  const fd = openSync(filePath, "r");
  try {
    const chunks: Buffer[] = [];
    const maxHeaderBytes = 64 * 1024;
    let position = 0;
    let foundNewline = false;

    while (position < maxHeaderBytes && !foundNewline) {
      const buffer = Buffer.allocUnsafe(Math.min(4096, maxHeaderBytes - position));
      const bytesRead = readSync(fd, buffer, 0, buffer.length, position);
      if (bytesRead === 0) break;
      const data = buffer.subarray(0, bytesRead);
      const newlineIndex = data.indexOf(0x0a);
      chunks.push(newlineIndex === -1 ? data : data.subarray(0, newlineIndex));
      position += bytesRead;
      foundNewline = newlineIndex !== -1;
    }

    if (!foundNewline && position >= maxHeaderBytes) return null;
    const firstLine = Buffer.concat(chunks).toString("utf8").trimEnd();
    if (!firstLine) return null;
    try {
      const header = JSON.parse(firstLine) as SessionHeader;
      return header.type === "session" ? header : null;
    } catch {
      return null;
    }
  } finally {
    closeSync(fd);
  }
}

export function getSessionEntries(filePath: string): SessionEntry[] {
  const entries = SessionManager.open(filePath).getEntries();