function parsePostMetadata(lines: string[]): PostMetadata[] {
    const result: PostMetadata[] = [];
    for (let line of lines) {
        const obj = JSON.parse(line);
        if (obj.type !== "metadata") {
            continue;
        }
        result.push({
            title: obj.title,
            description: obj.description,
            author: obj.author,
            date: new Date(obj.date),
        });
    }
    return result;
}