private void MergeCacheContexts(CacheContext into, CacheContext from)
{
into.AddContext(from.Contexts.ToArray());
into.AddTag(from.Tags.ToArray());
var offset = GetMostRestrictiveDateTimeOffset(into.ExpiresOn, from.ExpiresOn);
if (offset.HasValue)
{
into.WithExpiryOn(offset.Value);
}
var slidingExpiration = GetMostRestrictiveTimespan(into.ExpiresSliding, from.ExpiresSliding);
if (slidingExpiration.HasValue)
{
into.WithExpirySliding(slidingExpiration.Value);
}
var duration = GetMostRestrictiveTimespan(into.ExpiresAfter, from.ExpiresAfter);
if (duration.HasValue)
{
into.WithExpiryAfter(duration.Value);
}
}
/// <inheritdoc />
public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
if (output == null)
{
throw new ArgumentNullException(nameof(output));
}
IHtmlContent content;
if (Enabled)
{
var cacheContext = new CacheContext(CacheId);
if (!String.IsNullOrEmpty(VaryBy))
{
cacheContext.AddContext(VaryBy.Split(SplitChars, StringSplitOptions.RemoveEmptyEntries));
}
if (!String.IsNullOrEmpty(Dependencies))
{
cacheContext.AddTag(Dependencies.Split(SplitChars, StringSplitOptions.RemoveEmptyEntries));
}
var hasEvictionCriteria = false;
if (ExpiresOn.HasValue)
{
hasEvictionCriteria = true;
cacheContext.WithExpiryOn(ExpiresOn.Value);
}
if (ExpiresAfter.HasValue)
{
hasEvictionCriteria = true;
cacheContext.WithExpiryAfter(ExpiresAfter.Value);
}
if (ExpiresSliding.HasValue)
{
hasEvictionCriteria = true;
cacheContext.WithExpirySliding(ExpiresSliding.Value);
}
if (!hasEvictionCriteria)
{
cacheContext.WithExpirySliding(DefaultExpiration);
}
_cacheScopeManager.EnterScope(cacheContext);
try
{
content = await output.GetChildContentAsync();
}
finally
{
_cacheScopeManager.ExitScope();
}
content = await ProcessContentAsync(output, cacheContext);
}
else
{
content = await output.GetChildContentAsync();
}
// Clear the contents of the "cache" element since we don't want to render it.
output.SuppressOutput();
output.Content.SetHtmlContent(content);
}