public byte[] DownloadData(Uri uri, int fetchIntervalHrs, string userAgent)
{
if (fetchIntervalHrs == 0)
{
throw new ArgumentException("fetchIntervalHrs cannot be zero.", "fetchIntervalHrs");
}
System.DateTime?lastFetch = this.GetHTTPCacheLastUpdate(uri);
if (lastFetch != null)
{
if (lastFetch.Value.AddHours(fetchIntervalHrs) > DateTime.Now)
{
bool requestSuccess = false;
byte[] cacheData = this.GetHTTPCacheContent(uri, ref requestSuccess);
if (cacheData != null)
{
if (requestSuccess)
{
return(cacheData);
}
else
{
using (MemoryStream memoryStream = new MemoryStream(cacheData))
{
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter binaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
// Deserialise the CacheWebException structure
CacheWebExpInfo cachedException = default(CacheWebExpInfo);
cachedException = (CacheWebExpInfo)binaryFormatter.Deserialize(memoryStream);
// Crete a new WebException with the cached data and throw it
throw new WebException(cachedException.Message, cachedException.InnerException, cachedException.Status, cachedException.Response);
}
}
}
}
}
Debug.Print("CachedWebClient: Fetching " + uri.ToString());
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.UserAgent = userAgent;
request.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip");
using (MemoryStream dataStream = new MemoryStream())
{
try
{
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();
if (response.ContentEncoding.ToUpperInvariant() == "GZIP")
{
// Decompress the gzipped response while it is being read into the memory stream
responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
}
// Read the response into a MemoryStream in chunks, ready for the byte array
byte[] buffer = new byte[10240];
int readBytes;
while ((readBytes = responseStream.Read(buffer, 0, buffer.Length)) > 0)
{
dataStream.Write(buffer, 0, readBytes);
}
if (response.ContentEncoding.ToUpperInvariant() == "GZIP")
{
responseStream.Dispose();
}
}
catch (WebException webExp)
{
if (webExp.Status != WebExceptionStatus.NameResolutionFailure && webExp.Status != WebExceptionStatus.Timeout)
{
// A WebException doesn't serialise well, as Response and Status get lost,
// so store the information in a structure and then recreate it later
CacheWebExpInfo cacheException = new CacheWebExpInfo();
cacheException.Message = webExp.Message;
cacheException.InnerException = webExp.InnerException;
cacheException.Status = webExp.Status;
cacheException.Response = webExp.Response;
using (MemoryStream stream = new MemoryStream())
{
BinaryFormatter formatter = new BinaryFormatter();
// Serialise the CacheWebException and store it in the cache
formatter.Serialize(stream, cacheException);
this.AddToHTTPCache(uri, false, stream.ToArray());
}
}
// Re-throw the WebException
throw;
}
byte[] data = dataStream.ToArray();
this.AddToHTTPCache(uri, true, data);
return(data);
}
}
public byte[] DownloadData(Uri uri, int fetchIntervalHrs, string userAgent)
{
if (fetchIntervalHrs == 0)
{
throw new ArgumentException("fetchIntervalHrs cannot be zero.", "fetchIntervalHrs");
}
System.DateTime? lastFetch = this.GetHTTPCacheLastUpdate(uri);
if (lastFetch != null)
{
if (lastFetch.Value.AddHours(fetchIntervalHrs) > DateTime.Now)
{
bool requestSuccess = false;
byte[] cacheData = this.GetHTTPCacheContent(uri, ref requestSuccess);
if (cacheData != null)
{
if (requestSuccess)
{
return cacheData;
}
else
{
using (MemoryStream memoryStream = new MemoryStream(cacheData))
{
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter binaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
// Deserialise the CacheWebException structure
CacheWebExpInfo cachedException = default(CacheWebExpInfo);
cachedException = (CacheWebExpInfo)binaryFormatter.Deserialize(memoryStream);
// Crete a new WebException with the cached data and throw it
throw new WebException(cachedException.Message, cachedException.InnerException, cachedException.Status, cachedException.Response);
}
}
}
}
}
Debug.Print("CachedWebClient: Fetching " + uri.ToString());
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.UserAgent = userAgent;
request.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip");
using (MemoryStream dataStream = new MemoryStream())
{
try
{
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();
if (response.ContentEncoding.ToUpperInvariant() == "GZIP")
{
// Decompress the gzipped response while it is being read into the memory stream
responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
}
// Read the response into a MemoryStream in chunks, ready for the byte array
byte[] buffer = new byte[10240];
int readBytes;
while ((readBytes = responseStream.Read(buffer, 0, buffer.Length)) > 0)
{
dataStream.Write(buffer, 0, readBytes);
}
if (response.ContentEncoding.ToUpperInvariant() == "GZIP")
{
responseStream.Dispose();
}
}
catch (WebException webExp)
{
if (webExp.Status != WebExceptionStatus.NameResolutionFailure && webExp.Status != WebExceptionStatus.Timeout)
{
// A WebException doesn't serialise well, as Response and Status get lost,
// so store the information in a structure and then recreate it later
CacheWebExpInfo cacheException = new CacheWebExpInfo();
cacheException.Message = webExp.Message;
cacheException.InnerException = webExp.InnerException;
cacheException.Status = webExp.Status;
cacheException.Response = webExp.Response;
using (MemoryStream stream = new MemoryStream())
{
BinaryFormatter formatter = new BinaryFormatter();
// Serialise the CacheWebException and store it in the cache
formatter.Serialize(stream, cacheException);
this.AddToHTTPCache(uri, false, stream.ToArray());
}
}
// Re-throw the WebException
throw;
}
byte[] data = dataStream.ToArray();
this.AddToHTTPCache(uri, true, data);
return data;
}
}
