Internal/content preview (#691)

* updated comments

* added new databased entity preview content

* not works: map fileinfo to preview content

* get data from database if it exists

* create preview content from file info

* Failing tests - temp commit

* changed name varchar length

* added _ to sql script names

dspace-api/src/main/java/org/dspace/content/PreviewContent.java

@@ -0,0 +1,155 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.content;
+
+import java.util.Hashtable;
+import java.util.Map;
+import javax.persistence.CascadeType;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.JoinTable;
+import javax.persistence.ManyToOne;
+import javax.persistence.MapKeyColumn;
+import javax.persistence.OneToMany;
+import javax.persistence.SequenceGenerator;
+import javax.persistence.Table;
+
+import org.dspace.core.Context;
+import org.dspace.core.ReloadableEntity;
+
+/**
+ * Database entity representation of the previewcontent table.
+ * It is not possible to create entity from FileInfo class (without modifications)
+ * so we created PreviewContent (which serves as an entity for FileInfo)
+ * with corresponding database table previewcontent.
+ *
+ * @author Michaela Paurikova (dspace at dataquest.sk)
+ */
+@Entity
+@Table(name = "previewcontent")
+public class PreviewContent implements ReloadableEntity<Integer> {
+
+    @Id
+    @Column(name = "previewcontent_id")
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "previewcontent_previewcontent_id_seq")
+    @SequenceGenerator(name = "previewcontent_previewcontent_id_seq",
+            sequenceName = "previewcontent_previewcontent_id_seq", allocationSize = 1)
+    private Integer id;
+
+    @ManyToOne(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST})
+    @JoinColumn(name = "bitstream_id")
+    private Bitstream bitstream;
+
+    @Column(name = "name")
+    public String name;
+
+    @Column(name = "content")
+    public String content;
+
+    @Column(name = "isDirectory")
+    public boolean isDirectory;
+
+    @Column(name = "size")
+    public String size;
+
+    @OneToMany(cascade = CascadeType.ALL)
+    @JoinTable(
+            name = "preview2preview",
+            joinColumns = @JoinColumn(name = "parent_id"),
+            inverseJoinColumns = @JoinColumn(name = "child_id")
+    )
+    @MapKeyColumn(name = "name")
+    public Map<String, PreviewContent> sub = new Hashtable<>();
+
+    /**
+     * Protected constructor.
+     */
+    protected PreviewContent() {}
+
+    /**
+     * Protected constructor, create object using:
+     * {@link org.dspace.content.service.PreviewContentService#create(Context, PreviewContent)}
+     */
+    protected PreviewContent(PreviewContent previewContent) {
+        this.bitstream = previewContent.getBitstream();
+        this.name = previewContent.getName();
+        this.content = previewContent.getContent();
+        this.isDirectory = previewContent.isDirectory();
+        this.size = previewContent.getSize();
+        this.sub = previewContent.getSubPreviewContents();
+    }
+
+    /**
+     * Protected constructor, create object using:
+     * {@link org.dspace.content.service.PreviewContentService#create(Context, Bitstream, String, String, boolean,
+     * String, Map<String, PreviewContent>)}
+     */
+    protected PreviewContent(Bitstream bitstream, String name, String content, boolean isDirectory, String size,
+                             Map<String, PreviewContent> subPreviewContents) {
+        this.bitstream = bitstream;
+        this.name = name;
+        this.content = content;
+        this.isDirectory = isDirectory;
+        this.size = size;
+        this.sub = subPreviewContents;
+    }
+
+    @Override
+    public Integer getID() {
+        return id;
+    }
+
+    public Bitstream getBitstream() {
+        return bitstream;
+    }
+
+    public void setBitstream(Bitstream bitstream) {
+        this.bitstream = bitstream;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    public boolean isDirectory() {
+        return isDirectory;
+    }
+
+    public void setDirectory(boolean directory) {
+        isDirectory = directory;
+    }
+
+    public String getSize() {
+        return size;
+    }
+
+    public void setSize(String size) {
+        this.size = size;
+    }
+
+    public Map<String, PreviewContent> getSubPreviewContents() {
+        return sub;
+    }
+}

dspace-api/src/main/java/org/dspace/content/PreviewContentServiceImpl.java

@@ -0,0 +1,90 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.content;
+
+import java.sql.SQLException;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+import org.dspace.authorize.AuthorizeException;
+import org.dspace.authorize.service.AuthorizeService;
+import org.dspace.content.dao.PreviewContentDAO;
+import org.dspace.content.service.PreviewContentService;
+import org.dspace.core.Context;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+
+/**
+ * Service implementation for the PreviewContent object.
+ *
+ * @author Michaela Paurikova (dspace at dataquest.sk)
+ */
+public class PreviewContentServiceImpl implements PreviewContentService {
+
+    /**
+     * logger
+     */
+    private static final Logger log = LoggerFactory.getLogger(PreviewContentServiceImpl.class);
+
+
+    @Autowired
+    PreviewContentDAO previewContentDAO;
+    @Autowired(required = true)
+    AuthorizeService authorizeService;
+
+    @Override
+    public PreviewContent create(Context context, Bitstream bitstream, String name, String content,
+                                 boolean isDirectory, String size, Map<String, PreviewContent> subPreviewContents)
+            throws SQLException {
+        //no authorization required!
+        // Create a table row
+        PreviewContent previewContent = previewContentDAO.create(context, new PreviewContent(bitstream, name, content,
+                isDirectory, size, subPreviewContents));
+        log.info("Created new preview content of ID = {}", previewContent.getID());
+        return previewContent;
+    }
+
+    @Override
+    public PreviewContent create(Context context, PreviewContent previewContent) throws SQLException {
+        //no authorization required!
+        PreviewContent newPreviewContent = previewContentDAO.create(context, new PreviewContent(previewContent));
+        log.info("Created new preview content of ID = {}", newPreviewContent.getID());
+        return newPreviewContent;
+    }
+
+    @Override
+    public void delete(Context context, PreviewContent previewContent) throws SQLException, AuthorizeException {
+        if (!authorizeService.isAdmin(context)) {
+            throw new AuthorizeException(
+                    "You must be an admin to delete an CLARIN Content Preview");
+        }
+        previewContentDAO.delete(context, previewContent);
+    }
+
+    @Override
+    public PreviewContent find(Context context, int valueId) throws SQLException {
+        return previewContentDAO.findByID(context, PreviewContent.class, valueId);
+    }
+
+    @Override
+    public List<PreviewContent> findByBitstream(Context context, UUID bitstreamId) throws SQLException {
+        return previewContentDAO.findByBitstream(context, bitstreamId);
+    }
+
+    @Override
+    public List<PreviewContent> findRootByBitstream(Context context, UUID bitstreamId) throws SQLException {
+        return previewContentDAO.findRootByBitstream(context, bitstreamId);
+    }
+
+    @Override
+    public List<PreviewContent> findAll(Context context) throws SQLException {
+        return previewContentDAO.findAll(context, PreviewContent.class);
+    }
+}

dspace-api/src/main/java/org/dspace/content/dao/PreviewContentDAO.java

@@ -0,0 +1,44 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.content.dao;
+
+import java.sql.SQLException;
+import java.util.List;
+import java.util.UUID;
+
+import org.dspace.content.PreviewContent;
+import org.dspace.core.Context;
+import org.dspace.core.GenericDAO;
+
+/**
+ * Database Access Object interface class for the PreviewContent object.
+ * This class should only be accessed from a single service and should never be exposed outside of the API
+ *
+ * @author Michaela Paurikova (dspace at dataquest.sk)
+ */
+public interface PreviewContentDAO extends GenericDAO<PreviewContent> {
+    /**
+     * Find all preview content based on ID of bitstream the preview content is added to.
+     *
+     * @param context       DSpace context
+     * @param bitstreamId   The bitstream ID
+     * @return              List of found preview content
+     * @throws SQLException If a database error occurs
+     */
+    List<PreviewContent> findByBitstream(Context context, UUID bitstreamId) throws SQLException;
+
+    /**
+     *  Find all preview content based on bitstream that are the root directory.
+     *
+     * @param context       DSpace context
+     * @param bitstreamId   The bitstream ID
+     * @return              List of found preview content
+     * @throws SQLException If a database error occurs
+     */
+    List<PreviewContent> findRootByBitstream(Context context, UUID bitstreamId) throws SQLException;
+}

dspace-api/src/main/java/org/dspace/content/dao/impl/PreviewContentDAOImpl.java

@@ -0,0 +1,55 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.content.dao.impl;
+
+import java.sql.SQLException;
+import java.util.List;
+import java.util.UUID;
+import javax.persistence.Query;
+
+import org.dspace.content.PreviewContent;
+import org.dspace.content.dao.PreviewContentDAO;
+import org.dspace.core.AbstractHibernateDAO;
+import org.dspace.core.Context;
+
+/**
+ * Hibernate implementation of the Database Access Object interface class for the PreviewContent object.
+ * This class should never be accessed directly.
+ *
+ * @author Michaela Paurikova (dspace at dataquest.sk)
+ */
+public class PreviewContentDAOImpl extends AbstractHibernateDAO<PreviewContent> implements PreviewContentDAO {
+
+    protected PreviewContentDAOImpl() {
+        super();
+    }
+
+    @Override
+    public List<PreviewContent> findByBitstream(Context context, UUID bitstreamId) throws SQLException {
+        Query query = createQuery(context, "SELECT pc FROM " + PreviewContent.class.getSimpleName() +
+                        " as pc join pc.bitstream as b WHERE b.id = :bitstream_id");
+        query.setParameter("bitstream_id", bitstreamId);
+        query.setHint("org.hibernate.cacheable", Boolean.TRUE);
+        return findMany(context, query);
+    }
+
+    @Override
+    public List<PreviewContent> findRootByBitstream(Context context, UUID bitstreamId) throws SQLException {
+        // select only data from the previewcontent table whose ID is not a child in the preview2preview table
+        Query query = createQuery(context,
+                "SELECT pc FROM " + PreviewContent.class.getSimpleName() + " pc " +
+                        "JOIN pc.bitstream b " +
+                        "WHERE b.id = :bitstream_id " +
+                        "AND pc.id NOT IN (SELECT child.id FROM " + PreviewContent.class.getSimpleName() + " parent " +
+                        "JOIN parent.sub child)"
+        );
+        query.setParameter("bitstream_id", bitstreamId);
+        query.setHint("org.hibernate.cacheable", Boolean.TRUE);
+        return findMany(context, query);
+    }
+}

dspace-api/src/main/java/org/dspace/content/factory/ContentServiceFactory.java

@@ -29,6 +29,7 @@
 import org.dspace.content.service.MetadataFieldService;
 import org.dspace.content.service.MetadataSchemaService;
 import org.dspace.content.service.MetadataValueService;
+import org.dspace.content.service.PreviewContentService;
 import org.dspace.content.service.RelationshipService;
 import org.dspace.content.service.RelationshipTypeService;
 import org.dspace.content.service.SiteService;
@@ -76,6 +77,7 @@ public abstract class ContentServiceFactory {
     public abstract SiteService getSiteService();
 
     public abstract SubscribeService getSubscribeService();
+    public abstract PreviewContentService getPreviewContentService();
 
     /**
      * Return the implementation of the RelationshipTypeService interface

dspace-api/src/main/java/org/dspace/content/factory/ContentServiceFactoryImpl.java

@@ -26,6 +26,7 @@
 import org.dspace.content.service.MetadataFieldService;
 import org.dspace.content.service.MetadataSchemaService;
 import org.dspace.content.service.MetadataValueService;
+import org.dspace.content.service.PreviewContentService;
 import org.dspace.content.service.RelationshipService;
 import org.dspace.content.service.RelationshipTypeService;
 import org.dspace.content.service.SiteService;
@@ -83,6 +84,8 @@ public class ContentServiceFactoryImpl extends ContentServiceFactory {
     private EntityTypeService entityTypeService;
     @Autowired(required = true)
     private EntityService entityService;
+    @Autowired(required = true)
+    private PreviewContentService previewContentService;
 
     @Autowired(required = true)
     private DspaceObjectClarinService dspaceObjectClarinService;
@@ -165,6 +168,11 @@ public SubscribeService getSubscribeService() {
         return subscribeService ;
     }
 
+    @Override
+    public PreviewContentService getPreviewContentService() {
+        return previewContentService;
+    }
+
     @Override
     public RelationshipTypeService getRelationshipTypeService() {
         return relationshipTypeService;