/* 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 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "nsISupports.idl" #include "nsICache.idl" interface nsIInputStream; interface nsIOutputStream; interface nsICacheEntryDoomCallback; interface nsICacheListener; interface nsIFile; interface nsICacheEntryMetaDataVisitor; interface nsILoadContextInfo; [scriptable, uuid(607c2a2c-0a48-40b9-a956-8cf2bb9857cf)] interface nsICacheEntry : nsISupports { /** * 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 long 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); /** * 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; /** * 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. * * @return blocking, buffered output stream. */ nsIOutputStream openOutputStream(in long long offset); /** * Stores the Content-Length specified in the HTTP header for this * entry. Checked before we write to the cache entry, to prevent ever * taking up space in the cache for an entry that we know up front * is going to have to be evicted anyway. See bug 588507. */ attribute int64_t predictedDataSize; /** * Get/set security info on the cache entry for this descriptor. */ attribute nsISupports 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; /** * Opens and returns an output stream that a consumer may use to save an * alternate representation of the data. * @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. */ nsIOutputStream openAlternativeOutputStream(in ACString type); /** * 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); };