How to download a file with Puppeteer Sharp? - puppeteer-sharp

Question

Here is the code that works but it doesn't wait until the completion. How do I make sure the file has been saved?
var browser = await Puppeteer.LaunchAsync(new LaunchOptions
{
ExecutablePath = "C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe",
Headless = false,
});
var page = (await browser.PagesAsync()).First();
page.Response += async (object sender, ResponseCreatedEventArgs e) =>
{
if (e.Response.Url.Contains(".mp4"))
{
byte[] buff = await e.Response.BufferAsync();
File.WriteAllBytes($"{DateTime.UtcNow.ToFileTime()}.mp4", buff);
}
};
await page.GoToAsync("https://file-examples-com.github.io/uploads/2017/04/file_example_MP4_480_1_5MG.mp4");
await Task.Delay(30000);

Answer 1

Here, just wrote it:
public static async Task<FileInfo> DownloadFileAsync(string url)
{
try
{
await _page.GoToAsync(url);
}
catch (NavigationException)
{
// Trying to open a file page throws navigation exception, should be ignored
}
await _page.WaitForNetworkIdleAsync();
while (Directory.GetFiles(_downloadDirectory, "*.crdownload", SearchOption.AllDirectories).Length > 0)
{
await Task.Delay(250);
}
for (int i = 0; i < 100; i++)
{
var finishedFiles = (new DirectoryInfo(_downloadDirectory)).GetFiles();
var downloadedFile = finishedFiles.OrderByDescending(f => f.LastWriteTime).FirstOrDefault();
if (downloadedFile != null)
{
return downloadedFile!;
}
await Task.Delay(250);
}
throw new Exception($"Download failed for: {url}");
}