/// <summary>
/// This is the initialize state. This method does nothing.
/// </summary>
/// <param name="context">The current context.</param>
public override void Initialize(ResourceManagerContext context)
{
string subCommand = "";
if (context.Data.DestinationAddress.SubCommand is string)
subCommand =(string)context.Data.DestinationAddress.SubCommand;
switch (subCommand)
{
case "ETagFlush":
context.CheckChangeState("ETagCacheFlush");
break;
default:
context.CheckChangeState("OutputSelector");
break;
}
}
/// <summary>
/// This method selects the appropriate output style.
/// </summary>
/// <param name="context">The current context.</param>
public override void OutputSelect(ResourceManagerContext context)
{
string id = context.Request.Settings.OutputColl[0].OutputType;
switch (id)
{
case "file":
context.CheckChangeState("RS_OutputFile");
break;
case "resource":
context.CheckChangeState("RS_OutputResource");
break;
case "cds":
context.CheckChangeState("RS_OutputCDS");
break;
//case "app":
// context.CheckChangeState("RS_OutputAPP");
// break;
default:
throw new InvalidOutputCCException(@"Output format """ + id + @""" not recognised.");
}
}
/// <summary>
/// This method determines whether the entity has not been modified, and if so
/// simply instructs the calling party that that is the case.
/// </summary>
/// <param name="context">The current context.</param>
/// <returns>Returns false if the output logic should not be processed.</returns>
public override bool RequestValidate(ResourceManagerContext context)
{
//Check whether the request has an ETag.
string ETag = context.Request.Data.RequestIfNoneMatch;
context.CheckChangeState("OutputSelector");
if (ETag == null || ETag == "")
return true;
try
{
Guid vid = new Guid(ETag.Trim(new char[] { '"' }));
Guid? cid;
DateTime? expiry;
Type contentType;
if (!context.ContextSettings.ETagValidate(vid, out cid, out expiry, out contentType))
return true;
if (expiry.HasValue && expiry.Value > DateTime.Now)
{
context.Request.Data.ResponseHeaderAdd("Expires", CH.ConvertToRFC1123DateString(expiry.Value));
//set the cache control to public as we want these resources to be as cached as possible.
context.Request.Data.ResponseHeaderAdd("Cache-control", "public");
}
else if (!RevalidateAndUpdateETag(context, vid, cid.Value, contentType)) //OK, check the CDS to see if the content has changed.
{
context.Request.Data.ResponseHeaderAdd("X-debug", "cachehit revalidate fail");
return true;
}
else
context.Request.Data.ResponseHeaderAdd("Cache-control", "must-revalidate");
context.Request.Data.ResponseHeaderAdd("ETag", ETag);
context.Response.Status = CH.HTTPCodes.NotModified_304;
context.Response.Substatus = "Not Modified";
return false;
}
catch (Exception ex)
{
context.Request.Data.ResponseHeaderAdd("X-debug", "cachehit exception");
return true;
}
}
