public static async Task <(bool success, string?path)> DownloadFile(string uri)
{
var file = Path.Combine(cache, FileNameFromUrl.ConvertToFileName(uri));
if (File.Exists(file))
{
var fileTimestamp = Timestamp.GetTimestamp(file);
if (fileTimestamp.Expiry > DateTime.UtcNow)
{
return(true, file);
}
}
Timestamp webTimeStamp;
using (var request = new HttpRequestMessage(HttpMethod.Head, uri))
{
using var headResponse = await httpClient.SendAsync(request);
if (headResponse.StatusCode != HttpStatusCode.OK)
{
return(false, null);
}
webTimeStamp = Timestamp.GetTimestamp(headResponse);
if (File.Exists(file))
{
var fileTimestamp = Timestamp.GetTimestamp(file);
if (fileTimestamp.LastModified == webTimeStamp.LastModified)
{
return(true, file);
}
File.Delete(file);
}
}
using var response = await httpClient.GetAsync(uri);
using var httpStream = await response.Content.ReadAsStreamAsync();
using (var fileStream = new FileStream(file, FileMode.Create, FileAccess.Write, FileShare.None))
{
await httpStream.CopyToAsync(fileStream);
}
webTimeStamp = Timestamp.GetTimestamp(response);
Timestamp.SetTimestamp(file, webTimeStamp);
return(true, file);
}
public static async Task <string> DownloadFile(string requestUri)
{
var path = Path.Combine(cache, FileNameFromUrl.ConvertToFileName(requestUri));
if (File.Exists(path))
{
var fileTimestamp = Timestamp.GetTimestamp(path);
if (fileTimestamp.Expiry > DateTime.UtcNow)
{
return(File.ReadAllText(path));
}
}
var requestMessage = new HttpRequestMessage(HttpMethod.Head, requestUri);
Timestamp webTimeStamp;
using (var headResponse = await httpClient.SendAsync(requestMessage))
{
webTimeStamp = Timestamp.GetTimestamp(headResponse);
if (File.Exists(path))
{
var fileTimestamp = Timestamp.GetTimestamp(path);
if (fileTimestamp.LastModified == webTimeStamp.LastModified)
{
return(File.ReadAllText(path));
}
File.Delete(path);
}
}
using (var response = await httpClient.GetAsync(requestUri))
using (var httpStream = await response.Content.ReadAsStreamAsync())
{
using (var fileStream = new FileStream(path, FileMode.Create, FileAccess.Write, FileShare.None))
{
await httpStream.CopyToAsync(fileStream);
}
webTimeStamp = Timestamp.GetTimestamp(response);
Timestamp.SetTimestamp(path, webTimeStamp);
}
return(File.ReadAllText(path));
}
