/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (this.streamCachedImage)
{
// Write the blob storage directly to the stream
request.Method = "GET";
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
cachedStream.CopyTo(contextResponse.OutputStream);
ImageProcessingModule.SetHeaders(context, this.mimeType, null, this.MaxDays, response.StatusCode);
}
}
}
else
{
// Redirect the request to the blob URL
request.Method = "HEAD";
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
HttpStatusCode responseCode = response.StatusCode;
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(responseCode == HttpStatusCode.NotFound ? this.CachedPath : this.cachedRewritePath, false);
}
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (this.streamCachedImage)
{
// Write the blob storage directly to the stream
request.Method = "GET";
TryFiveTimes(
() =>
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
cachedStream.CopyTo(contextResponse.OutputStream);
ImageProcessingModule.SetHeaders(context, response.ContentType, null, this.BrowserMaxDays, response.StatusCode);
}
}
},
() =>
{
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to stream cached path: " + this.cachedRewritePath);
});
}
else
{
// Redirect the request to the blob URL
request.Method = "HEAD";
TryFiveTimes(
() =>
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
HttpStatusCode responseCode = response.StatusCode;
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(responseCode == HttpStatusCode.NotFound ? this.CachedPath : this.cachedRewritePath, false);
}
},
() =>
{
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to rewrite cached path to: " + this.cachedRewritePath);
});
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (this.streamCachedImage)
{
// Write the blob storage directly to the stream
request.Method = "GET";
TryFiveTimes(() =>
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
cachedStream.CopyTo(contextResponse.OutputStream);
// Mimetype can be null when returning from the cache.
ImageProcessingModule.SetHeaders(
context,
string.IsNullOrWhiteSpace(this.mimeType) ? contextResponse.ContentType : this.mimeType,
null,
this.MaxDays,
response.StatusCode);
}
}
});
}
else
{
// Redirect the request to the blob URL
request.Method = "HEAD";
TryFiveTimes(() =>
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
HttpStatusCode responseCode = response.StatusCode;
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(responseCode == HttpStatusCode.NotFound ? this.CachedPath : this.cachedRewritePath, false);
}
});
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (this.streamCachedImage)
{
// Map headers to enable 304s to pass through
if (context.Request.Headers["If-Modified-Since"] != null)
{
request.IfModifiedSince = DateTime.Parse(context.Request.Headers["If-Modified-Since"]);
}
string[] mapRequestHeaders = { "Cache-Control", "If-None-Match" };
foreach (string h in mapRequestHeaders)
{
if (context.Request.Headers[h] != null)
{
request.Headers.Add(h, context.Request.Headers[h]);
}
}
// Write the blob storage directly to the stream
request.Method = "GET";
TryFiveTimes(
() =>
{
HttpWebResponse response;
try
{
response = (HttpWebResponse)request.GetResponse();
}
catch (WebException ex)
{
// A 304 is not an error
if (((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.NotModified)
{
response = (HttpWebResponse)ex.Response;
}
else
{
throw;
}
}
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
contextResponse.Headers.Add("ETag", response.Headers["ETag"]);
contextResponse.Headers.Add("Last-Modified", response.Headers["Last-Modified"]);
cachedStream.CopyTo(contextResponse.OutputStream); // Will be empty on 304s
ImageProcessingModule.SetHeaders(context, response.StatusCode == HttpStatusCode.NotModified ? null : response.ContentType, null, this.BrowserMaxDays, response.StatusCode);
}
response.Dispose();
},
() =>
{
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to stream cached path: " + this.cachedRewritePath);
});
}
else
{
// Redirect the request to the blob URL
request.Method = "HEAD";
request.Timeout = this.timeout;
TryFiveTimes(
() =>
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
HttpStatusCode responseCode = response.StatusCode;
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(responseCode == HttpStatusCode.NotFound ? this.CachedPath : this.cachedRewritePath, false);
}
},
() =>
{
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to rewrite cached path to: " + this.cachedRewritePath);
});
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
if (streamCachedImage)
{
string blobPath = this.CachedPath.Substring(cloudCachedBlobContainer.Uri.ToString().Length + 1);
CloudBlockBlob blockBlob = cloudCachedBlobContainer.GetBlockBlobReference(blobPath);
if (blockBlob.Exists())
{
using (MemoryStream cachedStream = MemoryStreamPool.Shared.GetStream())
{
// Map headers to enable 304s to pass through
TrySetIfModifiedSinceDate(context, out AccessCondition accessCondition);
const string IfNoneMatch = "If-None-Match";
// TODO: Cache-Control?
if (context.Request.Headers[IfNoneMatch] != null)
{
accessCondition.IfNoneMatchETag = context.Request.Headers[IfNoneMatch];
}
bool is304 = false;
try
{
blockBlob.DownloadToStream(cachedStream, accessCondition);
cachedStream.Position = 0;
}
catch (StorageException ex)
{
// A 304 is not a true error, we still need to feed back.
var webException = ex.InnerException as WebException;
if (!(webException is null))
{
if (webException.Response != null && (((HttpWebResponse)webException.Response).StatusCode == HttpStatusCode.NotModified))
{
is304 = true;
}
else
{
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to stream cached path: " + this.cachedRewritePath);
return;
}
}
}
BlobProperties properties = blockBlob.Properties;
HttpResponse contextResponse = context.Response;
if (!string.IsNullOrWhiteSpace(properties.ETag))
{
contextResponse.Headers.Add("ETag", properties.ETag);
}
if (properties.LastModified.HasValue)
{
contextResponse.Headers.Add("Last-Modified", properties.LastModified.Value.UtcDateTime.ToString("R"));
}
cachedStream.CopyTo(contextResponse.OutputStream); // Will be empty on 304s
if (contextResponse.OutputStream.CanSeek)
{
contextResponse.OutputStream.Position = 0;
}
ImageProcessingModule.SetHeaders(
context,
!is304 ? properties.ContentType : null,
null,
this.BrowserMaxDays,
!is304 ? HttpStatusCode.OK : HttpStatusCode.NotModified);
}
}
}
else
{
// Prevent redundant metadata request if paths match.
if (this.CachedPath == this.cachedRewritePath)
{
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.CachedPath, false);
return;
}
var request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
// Redirect the request to the blob URL
request.Method = "HEAD";
request.Timeout = timeout;
HttpWebResponse response;
try
{
response = (HttpWebResponse)request.GetResponse();
response.Dispose();
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.cachedRewritePath, false);
}
catch (WebException ex)
{
response = (HttpWebResponse)ex.Response;
if (response != null)
{
HttpStatusCode responseCode = response.StatusCode;
// A 304 is not an error
// It appears that some CDN's on Azure (Akamai) do not work properly when making head requests.
// They will return a response url and other headers but a 500 status code.
if (responseCode == HttpStatusCode.NotModified ||
response.ResponseUri.AbsoluteUri.Equals(this.cachedRewritePath, StringComparison.OrdinalIgnoreCase))
{
response.Dispose();
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.cachedRewritePath, false);
}
else
{
response.Dispose();
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to rewrite cached path to: " + this.cachedRewritePath);
}
}
else
{
// It's a 404, we should redirect to the cached path we have just saved to.
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.CachedPath, false);
}
}
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (this.streamCachedImage)
{
// Map headers to enable 304s to pass through
if (context.Request.Headers["If-Modified-Since"] != null)
{
TrySetIfModifiedSinceDate(context, request);
}
string[] mapRequestHeaders = { "Cache-Control", "If-None-Match" };
foreach (string h in mapRequestHeaders)
{
if (context.Request.Headers[h] != null)
{
request.Headers.Add(h, context.Request.Headers[h]);
}
}
// Write the blob storage directly to the stream
request.Method = "GET";
request.Timeout = this.timeout;
HttpWebResponse response = null;
try
{
response = (HttpWebResponse)request.GetResponse();
}
catch (WebException ex)
{
// A 304 is not an error
if (ex.Response != null && ((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.NotModified)
{
response = (HttpWebResponse)ex.Response;
}
else
{
response?.Dispose();
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to stream cached path: " + this.cachedRewritePath);
return;
}
}
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
// If streaming but not using a CDN the headers will be null.
// See https://github.com/JimBobSquarePants/ImageProcessor/pull/466
string etagHeader = response.Headers["ETag"];
if (!string.IsNullOrWhiteSpace(etagHeader))
{
contextResponse.Headers.Add("ETag", etagHeader);
}
string lastModifiedHeader = response.Headers["Last-Modified"];
if (!string.IsNullOrWhiteSpace(lastModifiedHeader))
{
contextResponse.Headers.Add("Last-Modified", lastModifiedHeader);
}
cachedStream.CopyTo(contextResponse.OutputStream); // Will be empty on 304s
ImageProcessingModule.SetHeaders(
context,
response.StatusCode == HttpStatusCode.NotModified ? null : response.ContentType,
null,
this.BrowserMaxDays,
response.StatusCode);
}
cachedStream?.Dispose();
response.Dispose();
}
else
{
// Redirect the request to the blob URL
request.Method = "HEAD";
request.Timeout = this.timeout;
HttpWebResponse response;
try
{
response = (HttpWebResponse)request.GetResponse();
response.Dispose();
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.cachedRewritePath, false);
}
catch (WebException ex)
{
response = (HttpWebResponse)ex.Response;
if (response != null)
{
HttpStatusCode responseCode = response.StatusCode;
// A 304 is not an error
if (responseCode == HttpStatusCode.NotModified)
{
response.Dispose();
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.cachedRewritePath, false);
}
else
{
response.Dispose();
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>("Unable to rewrite cached path to: " + this.cachedRewritePath);
}
}
else
{
// It's a 404, we should redirect to the cached path we have just saved to.
ImageProcessingModule.AddCorsRequestHeaders(context);
context.Response.Redirect(this.CachedPath, false);
}
}
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
var request = (HttpWebRequest)WebRequest.Create(this.cachedRewritePath);
if (streamCachedImage)
{
// Map headers to enable 304s to pass through
if (context.Request.Headers["If-Modified-Since"] != null)
{
TrySetIfModifiedSinceDate(context, request);
}
string[] mapRequestHeaders = { "Cache-Control", "If-None-Match" };
foreach (string h in mapRequestHeaders)
{
if (context.Request.Headers[h] != null)
{
request.Headers.Add(h, context.Request.Headers[h]);
}
}
// Write the blob storage directly to the stream
request.Method = "GET";
request.Timeout = timeout;
HttpWebResponse response = null;
try
{
response = (HttpWebResponse)request.GetResponse();
}
catch (WebException ex)
{
// A 304 is not an error
// It appears that some CDN's on Azure (Akamai) do not work properly when making head requests.
// They will return a response url and other headers but a 500 status code.
if (ex.Response != null && (((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.NotModified ||
ex.Response.ResponseUri.AbsoluteUri.Equals(this.cachedRewritePath, StringComparison.OrdinalIgnoreCase)))
{
response = (HttpWebResponse)ex.Response;
}
else
{
response?.Dispose();
ImageProcessorBootstrapper.Instance.Logger.Log <AmazonS3Cache>("Unable to stream cached path: " + this.cachedRewritePath);
return;
}
}
Stream cachedStream = response.GetResponseStream();
if (cachedStream != null)
{
HttpResponse contextResponse = context.Response;
// If streaming but not using a CDN the headers will be null.
// See https://github.com/JimBobSquarePants/ImageProcessor/pull/466
string etagHeader = response.Headers["ETag"];
if (!string.IsNullOrWhiteSpace(etagHeader))
{
contextResponse.Headers.Add("ETag", etagHeader);
}
string lastModifiedHeader = response.Headers["Last-Modified"];
if (!string.IsNullOrWhiteSpace(lastModifiedHeader))
{
contextResponse.Headers.Add("Last-Modified", lastModifiedHeader);
}
cachedStream.CopyTo(contextResponse.OutputStream); // Will be empty on 304s
ImageProcessingModule.SetHeaders(
context,
response.StatusCode == HttpStatusCode.NotModified ? null : response.ContentType,
null,
this.BrowserMaxDays,
response.StatusCode);
}
cachedStream?.Dispose();
response.Dispose();
}
else
{
// Prevent redundant metadata request if paths match.
if (this.CachedPath == this.cachedRewritePath)
{
ImageProcessingModule.SetHeaders(context, null, null, this.BrowserMaxDays);
context.Response.Redirect(this.CachedPath, false);
return;
}
// Redirect the request to the blob URL
request.Method = "HEAD";
request.Timeout = timeout;
HttpWebResponse response = null;
try
{
response = (HttpWebResponse)request.GetResponse();
response.Dispose();
ImageProcessingModule.SetHeaders(context, null, null, this.BrowserMaxDays);
context.Response.Redirect(this.cachedRewritePath, false);
}
catch (WebException ex)
{
response = (HttpWebResponse)ex.Response;
if (response != null)
{
HttpStatusCode responseCode = response.StatusCode;
// A 304 is not an error
// It appears that some CDN's on Azure (Akamai) do not work properly when making head requests.
// They will return a response url and other headers but a 500 status code.
if (responseCode == HttpStatusCode.NotModified ||
response.ResponseUri.AbsoluteUri.Equals(this.cachedRewritePath, StringComparison.OrdinalIgnoreCase))
{
response.Dispose();
ImageProcessingModule.SetHeaders(context, null, null, this.BrowserMaxDays);
context.Response.Redirect(this.cachedRewritePath, false);
}
else
{
response.Dispose();
ImageProcessorBootstrapper.Instance.Logger.Log <AmazonS3Cache>("Unable to rewrite cached path to: " + this.cachedRewritePath);
}
}
else
{
// It's a 404, we should redirect to the cached path we have just saved to.
ImageProcessingModule.SetHeaders(context, null, null, this.BrowserMaxDays);
context.Response.Redirect(this.CachedPath, false);
}
}
}
}
/// <summary>
/// Rewrites the path to point to the cached image.
/// </summary>
/// <param name="context">
/// The <see cref="HttpContext"/> encapsulating all information about the request.
/// </param>
public override void RewritePath(HttpContext context)
{
if (streamCachedImage)
{
string blobPath = this.CachedPath.Substring(cloudCachedBlobContainer.Uri.ToString().Length + 1);
CloudBlockBlob blockBlob = cloudCachedBlobContainer.GetBlockBlobReference(blobPath);
if (blockBlob.Exists())
{
using (MemoryStream cachedStream = MemoryStreamPool.Shared.GetStream())
{
// Map headers to enable 304s to pass through
TrySetIfModifiedSinceDate(context, out AccessCondition accessCondition);
const string IfNoneMatch = "If-None-Match";
// TODO: Cache-Control?
if (context.Request.Headers[IfNoneMatch] != null)
{
accessCondition.IfNoneMatchETag = context.Request.Headers[IfNoneMatch];
}
bool is304 = false;
try
{
blockBlob.DownloadToStream(cachedStream, accessCondition);
cachedStream.Position = 0;
}
catch (StorageException ex)
{
// A 304 is not a true error, we still need to feed back.
if (ex.RequestInformation?.HttpStatusCode == (int)HttpStatusCode.NotModified)
{
is304 = true;
}
else if (ex.InnerException is WebException webException &&
webException.Response is HttpWebResponse httpWebResponse &&
httpWebResponse.StatusCode == HttpStatusCode.NotModified)
{
is304 = true;
}
else
{
var sb = new StringBuilder();
sb.AppendFormat("Unable to stream cached path: {0}", this.cachedRewritePath);
sb.AppendLine();
sb.AppendFormat("Exception: {0}", ex.ToString());
ImageProcessorBootstrapper.Instance.Logger.Log <AzureBlobCache>(sb.ToString());
return;
}
}
BlobProperties properties = blockBlob.Properties;
HttpResponse contextResponse = context.Response;
if (!string.IsNullOrWhiteSpace(properties.ETag))
{
contextResponse.Headers.Add("ETag", properties.ETag);
}
if (properties.LastModified.HasValue)
{
contextResponse.Headers.Add("Last-Modified", properties.LastModified.Value.UtcDateTime.ToString("R"));
}
cachedStream.CopyTo(contextResponse.OutputStream); // Will be empty on 304s
if (contextResponse.OutputStream.CanSeek)
{
contextResponse.OutputStream.Position = 0;
}
ImageProcessingModule.SetHeaders(
context,
!is304 ? properties.ContentType : null,
null,
this.BrowserMaxDays,
!is304 ? HttpStatusCode.OK : HttpStatusCode.NotModified);
}
