Interface ContentService

  • All Known Implementing Classes:
    ContentServiceImpl, RoutingContentService

    @AlfrescoPublicApi
    public interface ContentService
    Provides methods for accessing and transforming content.

    Implementations of this service are primarily responsible for ensuring that the correct store is used to access content, and that reads and writes for the same node reference are routed to the same store instance.

    The mechanism for selecting an appropriate store is not prescribed by the interface, but typically the decision will be made on the grounds of content type.

    Whereas the content stores have no knowledge of nodes other than their references, the ContentService is responsible for ensuring that all the relevant node-content relationships are maintained.

    Author:
    Derek Hulley
    See Also:
    ContentStore, ContentReader, ContentWriter
    • Method Detail

      • getStoreTotalSpace

        long getStoreTotalSpace()
        Gets the total space of the underlying content store (not exclusively Alfresco-controlled binaries).
        Returns:
        Returns the total, possibly approximate, size (in bytes) of of the store or -1 if no size data is available.
        Since:
        3.3.3
      • getStoreFreeSpace

        long getStoreFreeSpace()
        Gets the remaing available space in the underlying content store.
        Returns:
        Returns the total, possibly approximate, remaining space (in bytes) available to store content or -1 if no size data is available.
        Since:
        3.3.3
      • getRawReader

        @Auditable(parameters="contentUrl")
        ContentReader getRawReader​(String contentUrl)
        Fetch content from the low-level stores using a content URL. None of the metadata associated with the content will be populated. This method should be used only to stream the binary data out when no other metadata is required.

        null is never returned, but the reader should always be checked for existence.

        Parameters:
        contentUrl - a content store URL
        Returns:
        Returns a reader for the URL that needs to be checked.
      • getWriter

        @Auditable(parameters={"nodeRef","propertyQName","update"})
        ContentWriter getWriter​(NodeRef nodeRef,
                                QName propertyQName,
                                boolean update)
                         throws InvalidNodeRefException,
                                InvalidTypeException
        Get a content writer for the given node property, choosing to optionally have the node property updated automatically when the content stream closes.

        If the update flag is off, then the state of the node property will remain unchanged regardless of the state of the written binary data. If the flag is on, then the node property will be updated on the same thread as the code that closed the write channel.

        If no node is supplied, then the writer will provide a stream into the backing content store, but will not be associated with any new or previous content.

        NOTE: The content URL provided will be registered for automatic cleanup in the event that the transaction, in which this method was called, rolls back. If the transaction is successful, the writer may still be open and available for use but the underlying binary will not be cleaned up subsequently. The recommended pattern is to group calls to retrieve the writer in the same transaction as the calls to subsequently update and close the write stream - including setting of the related content properties.

        Parameters:
        nodeRef - a reference to a node having a content property, or null to just get a valid writer into a backing content store.
        propertyQName - the name of the property, which must be of type content
        update - true if the property must be updated atomically when the content write stream is closed (attaches a listener to the stream); false if the client code will perform the updates itself.
        Returns:
        Returns a writer for the content associated with the node property
        Throws:
        InvalidNodeRefException - if the node doesn't exist
        InvalidTypeException - if the node property is not of type content
      • getTempWriter

        @Auditable
        ContentWriter getTempWriter()
        Gets a writer to a temporary location. The longevity of the stored temporary content is determined by the system.
        Returns:
        Returns a writer onto a temporary location
      • isContentDirectUrlEnabled

        boolean isContentDirectUrlEnabled()
        Checks if the system and at least one store supports the retrieving of direct access URLs.
        Returns:
        true if direct access URLs retrieving is supported, false otherwise
      • isContentDirectUrlEnabled

        @Deprecated
        default boolean isContentDirectUrlEnabled​(NodeRef nodeRef)
        Deprecated.
        Checks if the system and store supports the retrieving of a direct access URL for the given node.
        Returns:
        true if direct access URLs retrieving is supported for the node, false otherwise
      • isContentDirectUrlEnabled

        boolean isContentDirectUrlEnabled​(NodeRef nodeRef,
                                          QName propertyQName)
        Checks if the system and store supports the retrieving of a direct access URL for the given node.
        Parameters:
        nodeRef - a reference to a node having a content property
        propertyQName - the name of the property, which must be of type content
        Returns:
        true if direct access URLs retrieving is supported for the node, false otherwise
      • requestContentDirectUrl

        @Deprecated
        default DirectAccessUrl requestContentDirectUrl​(NodeRef nodeRef,
                                                        boolean attachment)
        Deprecated.
        Gets a presigned URL to directly access the content. It is up to the actual store implementation if it can fulfil this request with an expiry time or not.
        Parameters:
        nodeRef - Node ref for which to obtain the direct access URL.
        attachment - true if an attachment URL is requested, false for an embedded URL.
        Returns:
        A direct access URL object for the content.
        Throws:
        UnsupportedOperationException - if the store is unable to provide the information.
      • requestContentDirectUrl

        default DirectAccessUrl requestContentDirectUrl​(NodeRef nodeRef,
                                                        QName propertyQName,
                                                        boolean attachment)
        Gets a presigned URL to directly access the content. It is up to the actual store implementation if it can fulfil this request with an expiry time or not.
        Parameters:
        nodeRef - Node ref for which to obtain the direct access URL.
        propertyQName - the name of the property, which must be of type content
        attachment - true if an attachment URL is requested, false for an embedded URL.
        Returns:
        A direct access URL object for the content.
        Throws:
        UnsupportedOperationException - if the store is unable to provide the information.
      • requestContentDirectUrl

        @Auditable(parameters={"nodeRef","validFor"})
        @Deprecated
        default DirectAccessUrl requestContentDirectUrl​(NodeRef nodeRef,
                                                        boolean attachment,
                                                        Long validFor)
        Deprecated.
        Gets a presigned URL to directly access the content. It is up to the actual store implementation if it can fulfil this request with an expiry time or not.
        Parameters:
        nodeRef - Node ref for which to obtain the direct access URL.
        attachment - true if an attachment URL is requested, false for an embedded URL.
        validFor - The time at which the direct access URL will expire.
        Returns:
        A direct access URL object for the content.
        Throws:
        UnsupportedOperationException - if the store is unable to provide the information.
      • requestContentDirectUrl

        @Auditable(parameters={"nodeRef","propertyQName","validFor"})
        DirectAccessUrl requestContentDirectUrl​(NodeRef nodeRef,
                                                QName propertyQName,
                                                boolean attachment,
                                                Long validFor)
        Gets a presigned URL to directly access the content. It is up to the actual store implementation if it can fulfil this request with an expiry time or not.
        Parameters:
        nodeRef - Node ref for which to obtain the direct access URL.
        propertyQName - the name of the property, which must be of type content
        attachment - true if an attachment URL is requested, false for an embedded URL.
        validFor - The time at which the direct access URL will expire.
        Returns:
        A direct access URL object for the content.
        Throws:
        UnsupportedOperationException - if the store is unable to provide the information.
      • getStorageProperties

        @Auditable
        @Experimental
        default Map<String,​String> getStorageProperties​(NodeRef nodeRef,
                                                              QName propertyQName)
        Gets a key-value (String-String) collection of storage headers/properties with their respective values for a specific node reference. A particular Cloud Connector will fill in that data with Cloud Storage Provider generic data. Map may be also filled in with entries consisting of pre-defined Alfresco keys of ObjectStorageProps and their values. If empty Map is returned - no connector is present or connector is not supporting retrieval of the properties or cannot determine the properties.
        Parameters:
        nodeRef - a reference to a node having a content property
        propertyQName - the name of the property, which must be of type content
        Returns:
        Returns a key-value (String-String) collection of storage headers/properties with their respective values for a given NodeRef.