private FileCacheItem UpdateFileCache(ContentGroupNode content_group, string cache_key)
{
CacheDependency cd;
StringBuilder merged = new StringBuilder();
List <string> merged_files = new List <string>(content_group.Files.Count);
// the embedded resource must be readed from the resource assembly.
Assembly assembly = Assembly.GetExecutingAssembly();
foreach (string file_name in content_group.Files)
{
string file_path = Path.Combine(content_group.BasePath, file_name);
// sanity check file existence
if (File.Exists(file_path))
{
using (StreamReader stream = new StreamReader(file_path)) {
string content = stream.ReadToEnd().Trim();
if (content.Length > 0)
{
merged.Append(content).Append("\r\n");
merged_files.Add(file_path);
}
stream.Close();
}
}
}
if (merged.Length > 0)
{
FileCacheItem ci = new FileCacheItem(merged.ToString());
// add the the application configuration file to the CacheDependency
merged_files.Add(Utility.BaseDirectory + "web.config");
cd = new CacheDependency(merged_files.ToArray());
// Store the FileCacheItem in cache w/ a dependency on the merged files changing
context_.Cache.Insert(cache_key, ci, cd);
return(ci);
}
return(null);
}
/// <summary>
/// Merges a collection of files into a single one and output its content to the requestor.
/// </summary>
/// <param name="files_to_merge">The files</param>
/// <param name="content_group_name">The name of the content group.</param>
/// <param name="content_type">The MIME type of content that will be merged.</param>
void GetMergedContent(string content_group_name, string mime_type)
{
string modified_since = context_.Request.Headers["If-Modified-Since"];
string cache_key = string.Concat(kKeyPrefix,
content_group_name, ".",
mime_type, ".",
kBuildVersion);
// check if this group is defined
ContentGroupNode content_group = settings_.WebNode.GetContentGroup(content_group_name, kBuildVersion, mime_type);
if (content_group == null)
{
context_.Response.StatusCode = kResourceNotFoundCode;
context_.Response.End();
return;
}
// attempt to retrieve the merged content from the cache
FileCacheItem cached_file = (FileCacheItem)context_.Cache[cache_key];
if (cached_file != null)
{
if (modified_since != null)
{
DateTime last_client_update;
DateTime.TryParseExact(context_.Request.Headers["If-Modified-Since"], "yyyyMMdd HH:mm:ss", null, System.Globalization.DateTimeStyles.None, out last_client_update);
if (cached_file.DateEntered <= last_client_update)
{
// don't do anything, nothing has changed since last request.
context_.Response.StatusCode = 304;
context_.Response.StatusDescription = "Not Modified";
context_.Response.End();
return;
}
}
else
{
// In the event that the browser does not automatically have this header, add it
context_.Response.AddHeader("If-Modified-Since", cached_file.DateEntered.ToString("yyyyMMdd HH:mm:ss"));
}
}
else
{
// cache item not found, update cache
cached_file = UpdateFileCache(content_group, cache_key);
if (cached_file == null)
{
// the files to merge are not found
FileLogger.ForCurrentProcess.Logger.Error("[GetMergedContent Nohros.Net.MergeHttpHandler] The files to merge are not found.");
context_.Response.StatusCode = kResourceNotFoundCode;
context_.Response.End();
}
}
context_.Response.Cache.SetLastModified(cached_file.DateEntered);
context_.Response.ContentType = mime_type;
context_.Response.Write(cached_file.Content);
context_.Response.End();
}
