Package org.nuxeo.ecm.core.blob

Class CachingBlobStore

java.lang.Object
org.nuxeo.ecm.core.blob.AbstractBlobStore
org.nuxeo.ecm.core.blob.CachingBlobStore
All Implemented Interfaces:
BlobStore
public class CachingBlobStore extends AbstractBlobStore
Blob store wrapper that caches blobs locally because fetching them may be expensive.
Since:
11.1

  • Field Details

    • LOCKED_FILES

      protected static final Set<Path> LOCKED_FILES

    • store

      protected final BlobStore store

    • cacheConfig

      protected final CachingConfiguration cacheConfig

    • cacheStore

      public final LocalBlobStore cacheStore

    • gc

      protected final BinaryGarbageCollector gc

    • clearOldBlobsLock

      protected final Lock clearOldBlobsLock

    • clearOldBlobsLastTime

      protected long clearOldBlobsLastTime

    • clearOldBlobsInterval

      protected long clearOldBlobsInterval

    • clock

      protected Clock clock

  • Constructor Details

  • Method Details

    • hasVersioning

      public boolean hasVersioning()
      Description copied from interface: BlobStore
      Whether this blob store has versioning.

      With versioning, two writes may use the same key. The returned keys will include a different version number to distinguish the writes.

      Specified by:
      hasVersioning in interface BlobStore
      Overrides:
      hasVersioning in class AbstractBlobStore

    • unwrap

      public BlobStore unwrap()
      Description copied from interface: BlobStore
      If this blob store wraps another one, returns it, otherwise returns this.
      Specified by:
      unwrap in interface BlobStore
      Overrides:
      unwrap in class AbstractBlobStore
      Returns:
      the lowest-level blob store

    • renameCachedBlob

      protected Path renameCachedBlob(String tmpKey, String key) throws IOException
      Throws:
      IOException

    • copyOrMoveCachedBlob

      protected Path copyOrMoveCachedBlob(String destKey, LocalBlobStore sourceStore, String sourceKey, boolean atomicMove) throws IOException
      Throws:
      IOException

    • writeBlobGeneric

      protected String writeBlobGeneric(BlobWriteContext blobWriteContext) throws IOException
      Description copied from class: AbstractBlobStore
      Writes the blob without using any store-to-store optimization.
      Overrides:
      writeBlobGeneric in class AbstractBlobStore
      Throws:
      IOException

    • copyOrMoveBlob

      public String copyOrMoveBlob(String key, BlobStore sourceStore, String sourceKey, boolean atomicMove) throws IOException
      Description copied from interface: BlobStore
      Writes a file based on a key, as an optimized copy/move from a source in another compatible blob store.

      The target key may be null, which is a signal from the caller that it has determined that deduplication is enabled and async digest computation is enabled, but the needed digest hasn't been computed, so this method should either find the digest in an efficient way if it can, or otherwise trigger an async digest computation.

      If the copy/move is requested to be atomic, then the destination file is created atomically. In case of atomic move, in some stores the destination will be created atomically but the source will only be deleted afterwards.

      The returned key may be different than the passed one when versioning is used.

      Parameters:
      key - the key; or null if the store should choose it or trigger async digest computation
      sourceStore - the source store
      sourceKey - the source key
      atomicMove - true for an atomic move, false for a regular copy
      Returns:
      the key of the copied/moved file, or null if copy/move failed
      Throws:
      IOException

    • useAsyncDigest

      public boolean useAsyncDigest()
      Description copied from class: AbstractBlobStore
      Whether this blob store is configured for async digest computation.
      Overrides:
      useAsyncDigest in class AbstractBlobStore

    • getFile

      public BlobStore.OptionalOrUnknown<Path> getFile(String key)
      Description copied from interface: BlobStore
      Gets an already-existing file containing the blob for the given key, if present.

      Note that this method is best-effort, it may return unknown even though the blob exists in the store, it's just that it's not handily available locally in a file.

      Parameters:
      key - the blob key
      Returns:
      the file containing the blob, or empty if the blob cannot be found, or unknown if no file is available locally

    • getFileFromCache

      protected BlobStore.OptionalOrUnknown<Path> getFileFromCache(String key, boolean exists)

    • getStream

      public BlobStore.OptionalOrUnknown<InputStream> getStream(String key) throws IOException
      Description copied from interface: BlobStore
      Gets the stream of the blob for the given key, if present.

      Note that this method is best-effort, it may return unknown even though the blob exists in the store, it's just that it's not efficient to return it as a stream.

      Parameters:
      key - the blob key
      Returns:
      the blob stream, or empty if the blob cannot be found, or unknown if no stream is efficiently available
      Throws:
      IOException

    • readBlob

      public boolean readBlob(String key, Path dest) throws IOException
      Description copied from interface: BlobStore
      Reads a blob based on its key into the given file.
      Parameters:
      key - the blob key
      dest - the file to use to store the fetched data
      Returns:
      true if the file was fetched, false if the file was not found
      Throws:
      IOException

    • writeBlobProperties

      public void writeBlobProperties(BlobUpdateContext blobUpdateContext) throws IOException
      Description copied from interface: BlobStore
      Sets properties on a blob.
      Specified by:
      writeBlobProperties in interface BlobStore
      Overrides:
      writeBlobProperties in class AbstractBlobStore
      Parameters:
      blobUpdateContext - the blob update context
      Throws:
      IOException

    • deleteBlob

      public void deleteBlob(String key)
      Description copied from interface: BlobStore
      Deletes a blob based on a key. No error occurs if the blob does not exist.

      This method does not throw IOException, but may log an error message.

      Parameters:
      key - the blob key

    • clear

      public void clear()
      Description copied from interface: BlobStore
      INTERNAL (TESTS). Clears the blob store of all its data.

    • clearOldBlobs

      protected void clearOldBlobs()
      Clear old blobs from the cache, but not too often (as doing directory listings has a cost).
      Since:
      11.5

    • clearOldBlobsNow

      protected void clearOldBlobsNow()
      Clear old blobs from the cache.

      A blob is deleted if it has not been recently created or accessed (minimum age), and if in addition it would be too big for the maximum cache size in bytes, or if the cache would contain too many blobs.

      Since:
      11.5

    • recordBlobAccess

      protected void recordBlobAccess(LocalBlobStore localBlobStore, String key)

    • recordBlobAccess

      protected void recordBlobAccess(Path path)
      Records access to a file by changing its modification time.

      Recording access is also a form of locking against concurrent deletion by the clearing mechanism.

      Since:
      11.5

    • tryLock

      protected static boolean tryLock(Path path)

    • unlock

      protected static void unlock(Path path)

    • getBinaryGarbageCollector

      public BinaryGarbageCollector getBinaryGarbageCollector()
      Description copied from interface: BlobStore
      Returns the binary garbage collector (GC).

      Several calls to this method will return the same GC, so that its status can be monitored using BinaryGarbageCollector.isInProgress().

      Returns:
      the binary GC