Context used by CssFilter under async flow. More...

#include "css_filter.h"

Inheritance diagram for net_instaweb::CssFilter::Context:

Public Member Functions
	Context (CssFilter filter, RewriteDriver driver, RewriteContext parent, CacheExtender cache_extender, ImageRewriteFilter image_rewriter, ImageCombineFilter image_combiner, ResourceContext *context)

void	SetupInlineRewrite (HtmlElement style_element, HtmlCharactersNode text)
	Setup rewriting for inline, attribute, or external CSS.

void	SetupAttributeRewrite (HtmlElement element, HtmlElement::Attribute src, InlineCssKind inline_css_kind)

void	SetupExternalRewrite (HtmlElement *element, const GoogleUrl &base_gurl, const GoogleUrl &trim_gurl)

void	RewriteCssFromNested (RewriteContext parent, CssHierarchy hierarchy)

virtual bool	SendFallbackResponse (StringPiece output_url_base, StringPiece input_contents, AsyncFetch async_fetch, MessageHandler handler)

CssResourceSlotFactory *	slot_factory ()

CssHierarchy *	mutable_hierarchy ()

Public Member Functions inherited from net_instaweb::SingleRewriteContext
	SingleRewriteContext (RewriteDriver driver, RewriteContext parent, ResourceContext *resource_context)

Public Member Functions inherited from net_instaweb::RewriteContext
	RewriteContext (RewriteDriver driver, RewriteContext parent, ResourceContext *resource_context)

int	num_slots () const

ResourceSlotPtr	slot (int index) const

int	num_outputs () const

OutputResourcePtr	output (int i) const

int	num_output_partitions () const

const CachedResult *	output_partition (int i) const

CachedResult *	mutable_output_partition (int i)

bool	chained () const

void	AddSlot (const ResourceSlotPtr &slot)

void	RemoveLastSlot ()

void	AddNestedContext (RewriteContext *context)

void	CallFetchInputs ()

void	CallLockFailed ()

void	CallStartFetchImpl ()

void	Initiate ()

bool	Fetch (const OutputResourcePtr &output_resource, AsyncFetch fetch, MessageHandler message_handler)

bool	slow () const

bool	is_metadata_cache_miss () const
	This particular rewrite was a metadata cache miss.

bool	has_parent () const
	Returns true if this is a nested rewriter.

bool	IsNestedIn (StringPiece id) const

void	CheckNotFrozen ()

RewriteContext *	parent ()
	Allows a nested rewriter to walk up its parent hierarchy.

const RewriteContext *	parent () const

int	num_nested () const
	Accessors for the nested rewrites.

RewriteContext *	nested (int i) const

RewriteDriver *	Driver () const

void	set_force_rewrite (bool x)
	If called with true, forces a rewrite and re-generates the output.

bool	rewrite_uncacheable () const

void	set_rewrite_uncacheable (bool rewrite_uncacheable)

const ResourceContext *	resource_context () const

GoogleString	ToString () const
	Returns debug information about this RewriteContext.

GoogleString	ToStringWithPrefix (StringPiece prefix) const

Protected Member Functions
bool	PolicyPermitsRendering () const override

void	Render () override

virtual void	Harvest ()

virtual bool	Partition (OutputPartitions partitions, OutputResourceVector outputs)
	SingleRewriteContext takes care of these methods from RewriteContext:

virtual void	RewriteSingle (const ResourcePtr &input, const OutputResourcePtr &output)
	Subclasses of SingleRewriteContext must override this:

virtual const char *	id () const
	Returns the filter ID.

virtual OutputResourceKind	kind () const

virtual GoogleString	CacheKeySuffix () const

virtual const UrlSegmentEncoder *	encoder () const

virtual GoogleString	UserAgentCacheKey (const ResourceContext *resource_context) const
	Implements UserAgentCacheKey method of RewriteContext.

Protected Member Functions inherited from net_instaweb::SingleRewriteContext
virtual void	Rewrite (int partition_index, CachedResult *partition, const OutputResourcePtr &output)

void	AddLinkRelCanonical (const ResourcePtr &input, ResponseHeaders *output)
	Adds a link: rel=canonical header pointing to the input URL as canonical.

void	AddLinkRelCanonicalForFallbackHeaders (ResponseHeaders *output)
	Helper for using above in FixFetchFallbackHeaders()

Protected Member Functions inherited from net_instaweb::RewriteContext
ServerContext *	FindServerContext () const

const RewriteOptions *	Options () const

OutputPartitions *	partitions ()

void	AddRecheckDependency ()

virtual bool	OptimizationOnly () const

virtual void	PartitionAsync (OutputPartitions partitions, OutputResourceVector outputs)

void	PartitionDone (RewriteResult result)

void	CrossThreadPartitionDone (RewriteResult result)

void	RewriteDone (RewriteResult result, int partition_index)

void	StartNestedTasks ()

bool	AreOutputsAllowedByCsp (CspDirective role) const
	Helper that checks that all output resources are OK with CSP as given role.

virtual void	WillNotRender ()

virtual void	Cancel ()

virtual void	EncodeUserAgentIntoResourceContext (ResourceContext *context)

void	AttachDependentRequestTrace (const StringPiece &label)

RequestTrace *	dependent_request_trace ()

void	TracePrintf (const char *fmt,...)

virtual void	StartFetchReconstruction ()

void	DetachFetch ()

virtual bool	DecodeFetchUrls (const OutputResourcePtr &output_resource, MessageHandler message_handler, GoogleUrlStarVector url_vector)

virtual void	FixFetchFallbackHeaders (const CachedResult &cached_result, ResponseHeaders *headers)

virtual void	FetchCallbackDone (bool success)

virtual void	FetchTryFallback (const GoogleString &url, const StringPiece &hash)

void	Freshen ()
	Freshens resources proactively to avoid expiration in the near future.

bool	notify_driver_on_fetch_done () const

void	set_notify_driver_on_fetch_done (bool value)

AsyncFetch *	async_fetch ()
	Note that the following must only be called in the fetch flow.

bool	FetchContextDetached ()
	Is fetch_ detached? Only call this in the fetch flow.

MessageHandler *	fetch_message_handler ()
	The message handler for the fetch.

bool	stale_rewrite () const
	Indicates whether we are serving a stale rewrite.

virtual int64	GetRewriteDeadlineAlarmMs () const

virtual bool	CreationLockBeforeStartFetch () const
	Should the context call LockForCreation before checking the cache?

virtual bool	FailOnHashMismatch () const

virtual bool	ScheduleNestedContextViaCentalController () const

void	ObtainLockForCreation (ServerContext server_context, Function callback)

void	ReleaseCreationLock (bool succeeded)

Additional Inherited Members
Public Types inherited from net_instaweb::RewriteContext
typedef std::vector< InputInfo * >	InputInfoStarVector

Static Public Member Functions inherited from net_instaweb::RewriteContext
static void	InitStats (Statistics *stats)
	Initializes statistics.

Static Public Attributes inherited from net_instaweb::RewriteContext
static const char	kNumRewritesAbandonedForLockContention []

static const char	kNumDeadlineAlarmInvocations []

static const char	kHashMismatchMessage []

Protected Types inherited from net_instaweb::RewriteContext
typedef std::vector< GoogleUrl * >	GoogleUrlStarVector

Static Protected Member Functions inherited from net_instaweb::RewriteContext
static bool	LookupMetadataForOutputResourceImpl (OutputResourcePtr output_resource, const GoogleUrl &gurl, RewriteContext rewrite_context, RewriteDriver driver, GoogleString error_out, CacheLookupResultCallback callback)

Detailed Description

Context used by CssFilter under async flow.

Member Function Documentation

virtual GoogleString net_instaweb::CssFilter::Context::CacheKeySuffix ( ) const

protectedvirtual

Allows subclasses to add additional text to be appended to the metadata cache key. The default implementation returns "".

Reimplemented from net_instaweb::RewriteContext.

virtual const UrlSegmentEncoder* net_instaweb::CssFilter::Context::encoder ( ) const

protectedvirtual

This final set of protected methods can be optionally overridden by subclasses. All RewriteContexts define how they encode URLs and other associated information needed for a rewrite into a URL. The default implementation handles a single URL with no extra data. The RewriteContext owns the encoder.

Todo:: TODO(jmarantz): remove the encoder from RewriteFilter.

Reimplemented from net_instaweb::RewriteContext.

virtual void net_instaweb::CssFilter::Context::Harvest ( )

protectedvirtual

Once any nested rewrites have completed, the results of these can be incorporated into the rewritten data. For contexts that do not require any nested RewriteContexts, it is OK to skip overriding this method – the empty default implementation is fine.

Reimplemented from net_instaweb::RewriteContext.

virtual OutputResourceKind net_instaweb::CssFilter::Context::kind ( ) const

inlineprotectedvirtual

Rewrites come in three flavors, as described in output_resource_kind.h, so this method must be defined by subclasses to indicate which it is.

For example, we will avoid caching output_resource content in the HTTP cache for rewrites that are so quick to complete that it's fine to do the rewrite on every request. extend_cache is obviously in this category, and it's arguable we could treat js minification that way too (though we don't at the moment).

Implements net_instaweb::RewriteContext.

bool net_instaweb::CssFilter::Context::PolicyPermitsRendering ( ) const

overrideprotectedvirtual

This method gives the context a chance to verify that rendering the result is consistent with the current document's (Content Security) Policy, which may be different than that of the page for which the result was first computed + cached. Most subclasses can just call AreOutputsAllowedByCsp(), with appropriate role.

Implements net_instaweb::RewriteContext.

void net_instaweb::CssFilter::Context::Render ( )

overrideprotectedvirtual

Performs rendering activities that span multiple HTML slots. For example, in a filter that combines N slots to 1, N-1 of the HTML elements might need to be removed. That can be performed in Render(). This method is optional; the base-class implementation is empty.

Note that unlike Harvest(), this method runs in the HTML thread (for top-level rewrites), and only runs if the rewrite completes prior to the rewrite-deadline. If the rewrite does make it by the deadline, RewriteContext::Render() will be invoked regardless of whether any slots were actually optimized successfully.

Reimplemented from net_instaweb::RewriteContext.

void net_instaweb::CssFilter::Context::RewriteCssFromNested	(	RewriteContext *	parent,
		CssHierarchy *	hierarchy
	)

Starts nested rewrite jobs for any imports or images contained in the CSS. Marked public, so that it's accessible from CssHierarchy.

virtual bool net_instaweb::CssFilter::Context::SendFallbackResponse	(	StringPiece	output_url_base,
		StringPiece	input_contents,
		AsyncFetch *	async_fetch,
		MessageHandler *	handler
	)

virtual

Specialization to absolutify URLs in input resource in case of rewrite fail or deadline exceeded.

Reimplemented from net_instaweb::RewriteContext.

The documentation for this class was generated from the following file:

net/instaweb/rewriter/public/css_filter.h

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation