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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "nsISupports.idl"
interface nsIAsyncOutputStream;
interface nsICacheEntryDoomCallback;
interface nsICacheEntryMetaDataVisitor;
interface nsIInputStream;
interface nsILoadContextInfo;
interface nsIOutputStream;
interface nsITransportSecurityInfo;
[scriptable, uuid(607c2a2c-0a48-40b9-a956-8cf2bb9857cf)]
interface nsICacheEntry : nsISupports
{
const unsigned long CONTENT_TYPE_UNKNOWN = 0;
const unsigned long CONTENT_TYPE_OTHER = 1;
const unsigned long CONTENT_TYPE_JAVASCRIPT = 2;
const unsigned long CONTENT_TYPE_IMAGE = 3;
const unsigned long CONTENT_TYPE_MEDIA = 4;
const unsigned long CONTENT_TYPE_STYLESHEET = 5;
const unsigned long CONTENT_TYPE_WASM = 6;
/**
* Content type that is used internally to check whether the value parsed
* from disk is within allowed limits. Don't pass CONTENT_TYPE_LAST to
* setContentType method.
*/
const unsigned long CONTENT_TYPE_LAST = 7;
/**
* Placeholder for the initial value of expiration time.
*/
const unsigned long NO_EXPIRATION_TIME = 0xFFFFFFFF;
/**
* Get the key identifying the cache entry.
*/
readonly attribute ACString key;
/**
* The unique ID for every nsICacheEntry instance, which can be used to check
* whether two pieces of information are from the same nsICacheEntry instance.
*/
readonly attribute uint64_t cacheEntryId;
/**
* Whether the entry is memory/only or persisted to disk.
* Note: private browsing entries are reported as persistent for consistency
* while are not actually persisted to disk.
*/
readonly attribute boolean persistent;
/**
* Get the number of times the cache entry has been opened.
*/
readonly attribute uint32_t fetchCount;
/**
* Get the last time the cache entry was opened (in seconds since the Epoch).
*/
readonly attribute uint32_t lastFetched;
/**
* Get the last time the cache entry was modified (in seconds since the Epoch).
*/
readonly attribute uint32_t lastModified;
/**
* Get the expiration time of the cache entry (in seconds since the Epoch).
*/
readonly attribute uint32_t expirationTime;
/**
* Set the time at which the cache entry should be considered invalid (in
* seconds since the Epoch).
*/
void setExpirationTime(in uint32_t expirationTime);
/**
* Get the last network response times for onStartReqeust/onStopRequest (in ms).
* @throws
* - NS_ERROR_NOT_AVAILABLE if onStartTime/onStopTime does not exist.
*/
readonly attribute uint64_t onStartTime;
readonly attribute uint64_t onStopTime;
/**
* Set the network response times for onStartReqeust/onStopRequest (in ms).
*/
void setNetworkTimes(in uint64_t onStartTime, in uint64_t onStopTime);
/**
* Set content type. Available types are defined at the begining of this file.
* The content type is used internally for cache partitioning and telemetry
* purposes so there is no getter.
*/
void setContentType(in uint8_t contentType);
/**
* This method is intended to override the per-spec cache validation
* decisions for a duration specified in seconds. The current state can
* be examined with isForcedValid (see below). This value is not persisted,
* so it will not survive session restart. Cache entries that are forced valid
* will not be evicted from the cache for the duration of forced validity.
* This means that there is a potential problem if the number of forced valid
* entries grows to take up more space than the cache size allows.
*
* NOTE: entries that have been forced valid will STILL be ignored by HTTP
* channels if they have expired AND the resource in question requires
* validation after expiring. This is to avoid using known-stale content.
*
* @param aSecondsToTheFuture
* the number of seconds the default cache validation behavior will be
* overridden before it returns to normal
*/
void forceValidFor(in unsigned long aSecondsToTheFuture);
/**
* The state variable for whether this entry is currently forced valid.
* Defaults to false for normal cache validation behavior, and will return
* true if the number of seconds set by forceValidFor() has yet to be reached.
*/
readonly attribute boolean isForcedValid;
/**
* This method gets called to mark the actual use of the forced-valid entry.
* This is necessary for telemetry, so when the entry eventually gets
* evicted we can report whether it was ever used or not.
* If the entry was not forced-valid, then this operation has no effect.
*/
void markForcedValidUse();
/**
* Open blocking input stream to cache data. Use the stream transport
* service to asynchronously read this stream on a background thread.
* The returned stream MAY implement nsISeekableStream.
*
* @param offset
* read starting from this offset into the cached data. an offset
* beyond the end of the stream has undefined consequences.
*
* @return non-blocking, buffered input stream.
*/
nsIInputStream openInputStream(in long long offset);
/**
* Open non-blocking output stream to cache data. The returned stream
* MAY implement nsISeekableStream.
*
* If opening an output stream to existing cached data, the data will be
* truncated to the specified offset.
*
* @param offset
* write starting from this offset into the cached data. an offset
* beyond the end of the stream has undefined consequences.
* @param predictedSize
* Predicted size of the data that will be written. It's used to decide
* whether the resulting entry would exceed size limit, in which case
* an error is thrown. If the size isn't known in advance, -1 should be
* passed.
*
* @return blocking, buffered output stream.
*/
nsIOutputStream openOutputStream(in long long offset, in long long predictedSize);
/**
* Get/set security info on the cache entry for this descriptor.
*/
attribute nsITransportSecurityInfo securityInfo;
/**
* Get the size of the cache entry data, as stored. This may differ
* from the entry's dataSize, if the entry is compressed.
*/
readonly attribute unsigned long storageDataSize;
/**
* Asynchronously doom an entry. Listener will be notified about the status
* of the operation. Null may be passed if caller doesn't care about the
* result.
*/
void asyncDoom(in nsICacheEntryDoomCallback listener);
/**
* Methods for accessing meta data. Meta data is a table of key/value
* string pairs. The strings do not have to conform to any particular
* charset, but they must be null terminated.
*/
string getMetaDataElement(in string key);
void setMetaDataElement(in string key, in string value);
/**
* Obtain the list of metadata keys this entry keeps.
*
* NOTE: The callback is invoked under the CacheFile's lock. It means
* there should not be made any calls to the entry from the visitor and
* if the values need to be processed somehow, it's better to cache them
* and process outside the callback.
*/
void visitMetaData(in nsICacheEntryMetaDataVisitor visitor);
/**
* Claims that all metadata on this entry are up-to-date and this entry
* now can be delivered to other waiting consumers.
*
* We need such method since metadata must be delivered synchronously.
*/
void metaDataReady();
/**
* Called by consumer upon 304/206 response from the server. This marks
* the entry content as positively revalidated.
* Consumer uses this method after the consumer has returned ENTRY_NEEDS_REVALIDATION
* result from onCacheEntryCheck and after successfull revalidation with the server.
*/
void setValid();
/**
* Explicitly tell the cache backend this consumer is no longer going to modify
* this cache entry data or metadata. In case the consumer was responsible to
* either of writing the cache entry or revalidating it, calling this method
* reverts the state to initial (as never written) or as not-validated and
* immediately notifies the next consumer in line waiting for this entry.
* This is the way to prevent deadlocks when someone else than the responsible
* channel references the cache entry being in a non-written or revalidating
* state.
*/
void dismiss();
/**
* Returns the size in kilobytes used to store the cache entry on disk.
*/
readonly attribute uint32_t diskStorageSizeInKB;
/**
* Doom this entry and open a new, empty, entry for write. Consumer has
* to exchange the entry this method is called on for the newly created.
* Used on 200 responses to conditional requests.
*
* @param aMemoryOnly
* - whether the entry is to be created as memory/only regardless how
* the entry being recreated persistence is set
* @returns
* - an entry that can be used to write to
* @throws
* - NS_ERROR_NOT_AVAILABLE when the entry cannot be from some reason
* recreated for write
*/
nsICacheEntry recreate([optional] in boolean aMemoryOnly);
/**
* Returns the length of data this entry holds.
* @throws
* NS_ERROR_IN_PROGRESS when the write is still in progress.
*/
readonly attribute long long dataSize;
/**
* Returns the length of data this entry holds.
* @throws
* - NS_ERROR_IN_PROGRESS when a write is still in progress (either real
content or alt data).
* - NS_ERROR_NOT_AVAILABLE if alt data does not exist.
*/
readonly attribute long long altDataSize;
/**
* Returns the type of the saved alt data.
* @throws
* - NS_ERROR_NOT_AVAILABLE if alt data does not exist.
*/
readonly attribute ACString altDataType;
/**
* Opens and returns an output stream that a consumer may use to save an
* alternate representation of the data.
*
* @param type
* type of the alternative data representation
* @param predictedSize
* Predicted size of the data that will be written. It's used to decide
* whether the resulting entry would exceed size limit, in which case
* an error is thrown. If the size isn't known in advance, -1 should be
* passed.
*
* @throws
* - NS_ERROR_NOT_AVAILABLE if the real data hasn't been written.
* - NS_ERROR_IN_PROGRESS when the writing regular content or alt-data to
* the cache entry is still in progress.
*
* If there is alt-data already saved, it will be overwritten.
*/
nsIAsyncOutputStream openAlternativeOutputStream(in ACString type, in long long predictedSize);
/**
* Opens and returns an input stream that can be used to read the alternative
* representation previously saved in the cache.
* If this call is made while writing alt-data is still in progress, it is
* still possible to read content from the input stream as it's being written.
* @throws
* - NS_ERROR_NOT_AVAILABLE if the alt-data representation doesn't exist at
* all or if alt-data of the given type doesn't exist.
*/
nsIInputStream openAlternativeInputStream(in ACString type);
/**
* Get the nsILoadContextInfo of the cache entry
*/
readonly attribute nsILoadContextInfo loadContextInfo;
/****************************************************************************
* The following methods might be added to some nsICacheEntryInternal
* interface since we want to remove them as soon as the old cache backend is
* completely removed.
*/
/**
* @deprecated
* FOR BACKWARD COMPATIBILITY ONLY
* When the old cache backend is eventually removed, this method
* can be removed too.
*
* In the new backend: this method is no-op
* In the old backend: this method delegates to nsICacheEntryDescriptor.close()
*/
void close();
/**
* @deprecated
* FOR BACKWARD COMPATIBILITY ONLY
* Marks the entry as valid so that others can use it and get only readonly
* access when the entry is held by the 1st writer.
*/
void markValid();
/**
* @deprecated
* FOR BACKWARD COMPATIBILITY ONLY
* Marks the entry as valid when write access is acquired.
*/
void maybeMarkValid();
/**
* @deprecated
* FOR BACKWARD COMPATIBILITY ONLY / KINDA HACK
* @param aWriteAllowed
* Consumer indicates whether write to the entry is allowed for it.
* Depends on implementation how the flag is handled.
* @returns
* true when write access is acquired for this entry,
* false otherwise
*/
boolean hasWriteAccess(in boolean aWriteAllowed);
};
/**
* Argument for nsICacheEntry.visitMetaData, provides access to all metadata
* keys and values stored on the entry.
*/
[scriptable, uuid(fea3e276-6ba5-4ceb-a581-807d1f43f6d0)]
interface nsICacheEntryMetaDataVisitor : nsISupports
{
/**
* Called over each key / value pair.
*/
void onMetaDataElement(in string key, in string value);
};