private async Task ProcessWithMemoryCache(HttpContext context, string cacheKey, ImageJobInfo info)
{
var isCached = memoryCache.TryGetValue(cacheKey, out ArraySegment <byte> imageBytes);
var isContentTypeCached = memoryCache.TryGetValue(cacheKey + ".contentType", out string contentType);
if (isCached && isContentTypeCached)
{
logger?.LogInformation("Serving {0}?{1} from memory cache", info.FinalVirtualPath, info.CommandString);
}
else
{
if (info.HasParams)
{
logger?.LogInformation($"Memory Cache Miss: Processing image {info.FinalVirtualPath}?{info.CommandString}");
var imageData = await info.ProcessUncached();
imageBytes = imageData.ResultBytes;
contentType = imageData.ContentType;
}
else
{
logger?.LogInformation($"Memory Cache Miss: Proxying image {info.FinalVirtualPath}?{info.CommandString}");
contentType = PathHelpers.ContentTypeForImageExtension(info.EstimatedFileExtension);
imageBytes = new ArraySegment <byte>(await info.GetPrimaryBlobBytesAsync());
}
// Set cache options.
var cacheEntryOptions = new MemoryCacheEntryOptions()
.SetSize(imageBytes.Count)
.SetSlidingExpiration(options.MemoryCacheSlidingExpiration);
var cacheEntryMetaOptions = new MemoryCacheEntryOptions()
.SetSize(contentType.Length * 2)
.SetSlidingExpiration(options.MemoryCacheSlidingExpiration);
memoryCache.Set(cacheKey, imageBytes, cacheEntryOptions);
memoryCache.Set(cacheKey + ".contentType", contentType, cacheEntryMetaOptions);
}
// write to stream
context.Response.ContentType = contentType;
context.Response.ContentLength = imageBytes.Count;
SetCachingHeaders(context, cacheKey);
await context.Response.Body.WriteAsync(imageBytes.Array, imageBytes.Offset, imageBytes.Count);
}
private async Task ProcessWithDistributedCache(HttpContext context, string cacheKey, ImageJobInfo info)
{
var imageBytes = await distributedCache.GetAsync(cacheKey);
var contentType = await distributedCache.GetStringAsync(cacheKey + ".contentType");
if (imageBytes != null && contentType != null)
{
logger?.LogInformation("Serving {0}?{1} from distributed cache", info.FinalVirtualPath, info.CommandString);
}
else
{
if (info.HasParams)
{
logger?.LogInformation($"Distributed Cache Miss: Processing image {info.FinalVirtualPath}?{info.CommandString}");
var imageData = await info.ProcessUncached();
imageBytes = imageData.ResultBytes.Count != imageData.ResultBytes.Array?.Length
? imageData.ResultBytes.ToArray()
: imageData.ResultBytes.Array;
contentType = imageData.ContentType;
}
else
{
logger?.LogInformation($"Distributed Cache Miss: Proxying image {info.FinalVirtualPath}?{info.CommandString}");
contentType = PathHelpers.ContentTypeForImageExtension(info.EstimatedFileExtension);
imageBytes = await info.GetPrimaryBlobBytesAsync();
}
// Set cache options.
var cacheEntryOptions = new DistributedCacheEntryOptions()
.SetSlidingExpiration(options.DistributedCacheSlidingExpiration);
await distributedCache.SetAsync(cacheKey, imageBytes, cacheEntryOptions);
await distributedCache.SetStringAsync(cacheKey + ".contentType", contentType, cacheEntryOptions);
}
// write to stream
context.Response.ContentType = contentType;
context.Response.ContentLength = imageBytes.Length;
SetCachingHeaders(context, cacheKey);
await context.Response.Body.WriteAsync(imageBytes, 0, imageBytes.Length);
}
private async Task ProcessWithStreamCache(HttpContext context, string cacheKey, ImageJobInfo info)
{
var keyBytes = Encoding.UTF8.GetBytes(cacheKey);
var typeName = streamCache.GetType().Name;
var cacheResult = await streamCache.GetOrCreateBytes(keyBytes, async (cancellationToken) =>
{
if (info.HasParams)
{
logger?.LogDebug("{CacheName} miss: Processing image {VirtualPath}?{Querystring}", typeName, info.FinalVirtualPath, info.ToString());
var result = await info.ProcessUncached();
if (result.ResultBytes.Array == null)
{
throw new InvalidOperationException("Image job returned zero bytes.");
}
return(new Tuple <string, ArraySegment <byte> >(result.ContentType, result.ResultBytes));
}
logger?.LogDebug("{CacheName} miss: Proxying image {VirtualPath}", typeName, info.FinalVirtualPath);
var bytes = await info.GetPrimaryBlobBytesAsync();
return(new Tuple <string, ArraySegment <byte> >(null, bytes));
}, CancellationToken.None, false);
if (cacheResult.Status != null)
{
GlobalPerf.Singleton.IncrementCounter($"{typeName}_{cacheResult.Status}");
}
if (cacheResult.Data != null)
{
await using (cacheResult.Data)
{
if (cacheResult.Data.Length < 1)
{
throw new InvalidOperationException($"{typeName} returned cache entry with zero bytes");
}
SetCachingHeaders(context, cacheKey);
await MagicBytes.ProxyToStream(cacheResult.Data, context.Response);
}
logger?.LogDebug("Serving from {CacheName} {VirtualPath}?{CommandString}", typeName, info.FinalVirtualPath, info.CommandString);
}
else
{
// TODO explore this failure path better
throw new NullReferenceException("Caching failed: " + cacheResult.Status);
}
}
private async Task ProcessWithSqliteCache(HttpContext context, string cacheKey, ImageJobInfo info)
{
var cacheResult = await sqliteCache.GetOrCreate(cacheKey, async() =>
{
if (info.HasParams)
{
logger?.LogInformation($"Sqlite Cache Miss: Processing image {info.FinalVirtualPath}?{info.CommandString}");
var imageData = await info.ProcessUncached();
var imageBytes = imageData.ResultBytes.Count != imageData.ResultBytes.Array?.Length
? imageData.ResultBytes.ToArray()
: imageData.ResultBytes.Array;
var contentType = imageData.ContentType;
return(new SqliteCacheEntry()
{
ContentType = contentType,
Data = imageBytes
});
}
else
{
logger?.LogInformation($"Sqlite Cache Miss: Proxying image {info.FinalVirtualPath}?{info.CommandString}");
var contentType = PathHelpers.ContentTypeForImageExtension(info.EstimatedFileExtension);
return(new SqliteCacheEntry()
{
ContentType = contentType,
Data = await info.GetPrimaryBlobBytesAsync()
});
}
});
// write to stream
context.Response.ContentType = cacheResult.ContentType;
context.Response.ContentLength = cacheResult.Data.Length;
SetCachingHeaders(context, cacheKey);
await context.Response.Body.WriteAsync(cacheResult.Data, 0, cacheResult.Data.Length);
}
