API for object pagination, count(*)

build.gradle

@@ -11,7 +11,7 @@ allprojects {
     group = 'org.vitrivr'
 
     /* Our current version, on dev branch this should always be release+1-SNAPSHOT */
-    version = '3.11.0'
+    version = '3.11.1'
 
     apply plugin: 'java-library'
     apply plugin: 'maven-publish'

cineast-api/src/main/java/org/vitrivr/cineast/api/APIEndpoint.java

@@ -25,9 +25,11 @@
 import org.vitrivr.cineast.api.rest.handlers.actions.feature.FindSegmentFeaturesGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.feature.FindSegmentTextGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.feature.FindTagsForElementGetHandler;
+import org.vitrivr.cineast.api.rest.handlers.actions.bool.CountRowsGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.mediaobject.FindObjectAllGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.mediaobject.FindObjectByIdPostHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.mediaobject.FindObjectGetHandler;
+import org.vitrivr.cineast.api.rest.handlers.actions.mediaobject.FindObjectPaginationGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataByDomainGetHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataByDomainPostHandler;
 import org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataByKeyGetHandler;
@@ -401,6 +403,7 @@ private void registerRestOperations() {
         new FindObjectAllGetHandler(),
         new FindObjectByIdPostHandler(),
         new FindObjectGetHandler(),
+        new FindObjectPaginationGetHandler(),
         /* Segments */
         new FindSegmentByIdPostHandler(),
         new FindSegmentsByIdGetHandler(),
@@ -427,6 +430,7 @@ private void registerRestOperations() {
         /* Boolean */
         new FindDistinctElementsByColumnPostHandler(),
         new SelectFromTablePostHandler(),
+        new CountRowsGetHandler(),
         /* Status */
         new StatusInvocationHandler()
     ));

cineast-api/src/main/java/org/vitrivr/cineast/api/messages/general/IntegerMessage.java

@@ -0,0 +1,18 @@
+package org.vitrivr.cineast.api.messages.general;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class IntegerMessage {
+
+  private final int value;
+
+  @JsonCreator
+  public IntegerMessage(@JsonProperty("value") int value) {
+    this.value = value;
+  }
+
+  public int getValue() {
+    return value;
+  }
+}

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/bool/CountRowsGetHandler.java

@@ -0,0 +1,52 @@
+package org.vitrivr.cineast.api.rest.handlers.actions.bool;
+
+import static org.vitrivr.cineast.api.util.APIConstants.TABLE_NAME;
+
+import io.javalin.http.Context;
+import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
+import io.javalin.plugin.openapi.dsl.OpenApiDocumentation;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.vitrivr.cineast.api.messages.general.IntegerMessage;
+import org.vitrivr.cineast.api.rest.handlers.interfaces.GetRestHandler;
+import org.vitrivr.cineast.standalone.config.Config;
+
+public class CountRowsGetHandler implements GetRestHandler<IntegerMessage> {
+
+  public static final String ROUTE = "count/table/{" + TABLE_NAME + "}";
+
+  private static final Logger LOGGER = LogManager.getLogger(CountRowsGetHandler.class);
+
+  @Override
+  public IntegerMessage doGet(Context ctx) {
+    try (final var selector = Config.sharedConfig().getDatabase().getSelectorSupplier().get()) {
+      var tableName = ctx.pathParam(TABLE_NAME);
+      selector.open(tableName);
+      var count = selector.rowCount();
+      LOGGER.trace("counted {} objects in table {}", count, tableName);
+      return new IntegerMessage(count);
+    }
+  }
+
+  @Override
+  public Class<IntegerMessage> outClass() {
+    return IntegerMessage.class;
+  }
+
+  @Override
+  public String route() {
+    return ROUTE;
+  }
+
+  @Override
+  public OpenApiDocumentation docs() {
+    return OpenApiBuilder.document()
+        .operation(op -> {
+          op.summary("Count objects");
+          op.description("Equivalent to calling SELECT count(*) FROM table. Used to determined #pages for pagination in a frontend or statistical purposes");
+          op.operationId("countRows");
+          op.addTagsItem("Misc");
+        })
+        .json("200", outClass());
+  }
+}

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/feature/FindSegmentFeaturesGetHandler.java

@@ -11,8 +11,7 @@
 import org.vitrivr.cineast.api.rest.handlers.interfaces.GetRestHandler;
 import org.vitrivr.cineast.api.util.QueryUtil;
 
-public class FindSegmentFeaturesGetHandler implements
-    GetRestHandler<FeaturesAllCategoriesQueryResult> {
+public class FindSegmentFeaturesGetHandler implements GetRestHandler<FeaturesAllCategoriesQueryResult> {
 
   public static final String ROUTE = "find/feature/all/by/id/{" + ID_QUALIFIER + "}";
 

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/mediaobject/FindObjectAllGetHandler.java

@@ -3,28 +3,20 @@
 import io.javalin.http.Context;
 import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
 import io.javalin.plugin.openapi.dsl.OpenApiDocumentation;
-import java.util.List;
 import org.vitrivr.cineast.api.messages.result.MediaObjectQueryResult;
 import org.vitrivr.cineast.api.rest.handlers.interfaces.GetRestHandler;
-import org.vitrivr.cineast.core.data.entities.MediaObjectDescriptor;
 import org.vitrivr.cineast.core.db.dao.reader.MediaObjectReader;
 import org.vitrivr.cineast.standalone.config.Config;
 
 public class FindObjectAllGetHandler implements GetRestHandler<MediaObjectQueryResult> {
 
-
-  public static final String TYPE_NAME = "type";
-
   public static final String ROUTE = "find/objects/all/"; // The more honest route
-//  public static final String ROUTE = "find/objects/all/:"+TYPE_NAME;
 
   @Override
   public MediaObjectQueryResult doGet(Context ctx) {
-    // TODO :type is not being used
-    final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get());
-    final List<MediaObjectDescriptor> multimediaobjectIds = ol.getAllObjects();
-    ol.close();
-    return new MediaObjectQueryResult("", multimediaobjectIds);
+    try (final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get())) {
+      return new MediaObjectQueryResult("", ol.getAllObjects());
+    }
   }
 
   @Override

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/mediaobject/FindObjectByIdPostHandler.java

@@ -19,14 +19,12 @@ public class FindObjectByIdPostHandler implements ParsingPostRestHandler<IdList,
 
   @Override
   public MediaObjectQueryResult performPost(IdList context, Context ctx) {
-    final Map<String, String> parameters = ctx.pathParamMap();
     if (context == null || context.getIds().length == 0) {
       return new MediaObjectQueryResult("", new ArrayList<>(0));
     }
-    final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get());
-    final Map<String, MediaObjectDescriptor> objects = ol.lookUpObjects(Arrays.asList(context.getIds()));
-    ol.close();
-    return new MediaObjectQueryResult("", new ArrayList<>(objects.values()));
+    try (final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get())) {
+      return new MediaObjectQueryResult("", new ArrayList<>(ol.lookUpObjects(Arrays.asList(context.getIds())).values()));
+    }
   }
 
   @Override

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/mediaobject/FindObjectGetHandler.java

@@ -1,5 +1,8 @@
 package org.vitrivr.cineast.api.rest.handlers.actions.mediaobject;
 
+import static org.vitrivr.cineast.api.util.APIConstants.ATTRIBUTE_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.VALUE_NAME;
+
 import com.google.common.collect.Lists;
 import io.javalin.http.Context;
 import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
@@ -15,44 +18,38 @@
 
 public class FindObjectGetHandler implements GetRestHandler<MediaObjectQueryResult> {
 
-  public static final String ATTRIBUTE_NAME = "attribute";
-  public static final String VALUE_NAME = "value";
-
   public static final String ROUTE = "find/object/by/{" + ATTRIBUTE_NAME + "}/{" + VALUE_NAME + "}";
 
   private static final Logger LOGGER = LogManager.getLogger(FindObjectGetHandler.class);
 
-
   @Override
   public MediaObjectQueryResult doGet(Context ctx) {
     final Map<String, String> parameters = ctx.pathParamMap();
 
     final String attribute = parameters.get(ATTRIBUTE_NAME);
     final String value = parameters.get(VALUE_NAME);
 
-    final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get());
-    MediaObjectDescriptor object = null;
-
-    switch (attribute.toLowerCase()) {
-      case "id": {
-        object = ol.lookUpObjectById(value);
-        break;
-      }
-      case "name": {
-        object = ol.lookUpObjectByName(value);
-        break;
-      }
-      case "path": {
-        object = ol.lookUpObjectByPath(value);
-        break;
-      }
-      default: {
-        LOGGER.error("Unknown attribute '{}' in FindObjectByActionHandler", attribute);
+    try (final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get())) {
+      MediaObjectDescriptor object = null;
+      switch (attribute.toLowerCase()) {
+        case "id": {
+          object = ol.lookUpObjectById(value);
+          break;
+        }
+        case "name": {
+          object = ol.lookUpObjectByName(value);
+          break;
+        }
+        case "path": {
+          object = ol.lookUpObjectByPath(value);
+          break;
+        }
+        default: {
+          LOGGER.error("Unknown attribute '{}' in FindObjectByActionHandler", attribute);
+        }
       }
+      return new MediaObjectQueryResult("", Lists.newArrayList(object));
     }
-
-    ol.close();
-    return new MediaObjectQueryResult("", Lists.newArrayList(object));
   }
 
   @Override
@@ -75,6 +72,7 @@ public OpenApiDocumentation docs() {
           op.addTagsItem("Object");
         })
         .pathParam(ATTRIBUTE_NAME, String.class, p -> p.description("The attribute type of the value. One of: id, name, path"))
+        .pathParam(VALUE_NAME, String.class, p -> p.description("The actual value that you want to filter for"))
         .json("200", outClass());
   }
 }

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/mediaobject/FindObjectPaginationGetHandler.java

@@ -0,0 +1,66 @@
+package org.vitrivr.cineast.api.rest.handlers.actions.mediaobject;
+
+import static org.vitrivr.cineast.api.util.APIConstants.LIMIT_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.SKIP_NAME;
+
+import io.javalin.http.Context;
+import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
+import io.javalin.plugin.openapi.dsl.OpenApiDocumentation;
+import java.util.ArrayList;
+import java.util.Map;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.vitrivr.cineast.api.messages.result.MediaObjectQueryResult;
+import org.vitrivr.cineast.api.rest.handlers.interfaces.GetRestHandler;
+import org.vitrivr.cineast.core.db.dao.reader.MediaObjectReader;
+import org.vitrivr.cineast.standalone.config.Config;
+
+public class FindObjectPaginationGetHandler implements GetRestHandler<MediaObjectQueryResult> {
+
+  public static final String ROUTE = "find/object/all/{" + SKIP_NAME + "}/{" + LIMIT_NAME + "}";
+
+  private static final Logger LOGGER = LogManager.getLogger(FindObjectPaginationGetHandler.class);
+
+  @Override
+  public MediaObjectQueryResult doGet(Context ctx) {
+    final Map<String, String> parameters = ctx.pathParamMap();
+
+    try (final MediaObjectReader ol = new MediaObjectReader(Config.sharedConfig().getDatabase().getSelectorSupplier().get())) {
+      final var skipParam = parameters.get(SKIP_NAME);
+      final var skip = skipParam == null ? 0 : Integer.parseInt(skipParam);
+      final var limitParam = parameters.get(LIMIT_NAME);
+      final var limit = limitParam == null ? Integer.MAX_VALUE : Integer.parseInt(limitParam);
+
+      var result = ol.getAllObjects(skip, limit);
+      LOGGER.trace("returning {} elements for skip {} and limit {}", result.size(), skip, limit);
+      return new MediaObjectQueryResult("", result);
+    } catch (Exception e) {
+      LOGGER.error("Error during request", e);
+      return new MediaObjectQueryResult("", new ArrayList<>());
+    }
+  }
+
+  @Override
+  public Class<MediaObjectQueryResult> outClass() {
+    return MediaObjectQueryResult.class;
+  }
+
+  @Override
+  public String route() {
+    return ROUTE;
+  }
+
+  @Override
+  public OpenApiDocumentation docs() {
+    return OpenApiBuilder.document()
+        .operation(op -> {
+          op.summary("Get a fixed amount of objects from the sorted list");
+          op.description("Equivalent to calling SELECT * FROM multimediaobject ORDER BY objectid ASC LIMIT limit SKIP skip. Mostly used for pagination when wanting to retrieve all objects");
+          op.operationId("findObjectsPagination");
+          op.addTagsItem("Object");
+        })
+        .pathParam(LIMIT_NAME, Integer.class, p -> p.description("How many object at most should be fetched"))
+        .pathParam(SKIP_NAME, Integer.class, p -> p.description("How many objects should be skipped"))
+        .json("200", outClass());
+  }
+}

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/metadata/FindObjectMetadataByDomainGetHandler.java

@@ -1,7 +1,7 @@
 package org.vitrivr.cineast.api.rest.handlers.actions.metadata;
 
-import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.DOMAIN_NAME;
 import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.OBJECT_ID_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.DOMAIN_NAME;
 
 import io.javalin.http.Context;
 import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
@@ -21,17 +21,15 @@
 public class FindObjectMetadataByDomainGetHandler implements GetRestHandler<MediaObjectMetadataQueryResult> {
 
 
-  public static final String ROUTE = "find/metadata/in/{" + DOMAIN_NAME + "}/by/id/{" + APIConstants.ID_QUALIFIER
-      + "}";
+  public static final String ROUTE = "find/metadata/in/{" + DOMAIN_NAME + "}/by/id/{" + APIConstants.ID_QUALIFIER + "}";
 
   @Override
   public MediaObjectMetadataQueryResult doGet(Context ctx) {
     final Map<String, String> parameters = ctx.pathParamMap();
     final String objectId = parameters.get(OBJECT_ID_NAME);
     final String domain = parameters.get(DOMAIN_NAME);
     final MetadataRetrievalService service = new MetadataRetrievalService();
-    return new MediaObjectMetadataQueryResult("",
-        service.findByDomain(objectId, domain));
+    return new MediaObjectMetadataQueryResult("", service.findByDomain(objectId, domain));
   }
 
   @Override

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/metadata/FindObjectMetadataByDomainPostHandler.java

@@ -1,6 +1,6 @@
 package org.vitrivr.cineast.api.rest.handlers.actions.metadata;
 
-import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.DOMAIN_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.DOMAIN_NAME;
 
 import io.javalin.http.Context;
 import io.javalin.plugin.openapi.dsl.OpenApiBuilder;
@@ -33,8 +33,7 @@ public MediaObjectMetadataQueryResult performPost(IdList ids, Context ctx) {
     }
     final String domain = parameters.get(DOMAIN_NAME);
     final MetadataRetrievalService service = new MetadataRetrievalService();
-    return new MediaObjectMetadataQueryResult("",
-        service.findByDomain(ids.getIdList(), domain));
+    return new MediaObjectMetadataQueryResult("", service.findByDomain(ids.getIdList(), domain));
   }
 
   @Override

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/metadata/FindObjectMetadataByKeyGetHandler.java

@@ -1,6 +1,6 @@
 package org.vitrivr.cineast.api.rest.handlers.actions.metadata;
 
-import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.KEY_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.KEY_NAME;
 import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.OBJECT_ID_NAME;
 
 import io.javalin.http.Context;

cineast-api/src/main/java/org/vitrivr/cineast/api/rest/handlers/actions/metadata/FindObjectMetadataByKeyPostHandler.java

@@ -1,6 +1,6 @@
 package org.vitrivr.cineast.api.rest.handlers.actions.metadata;
 
-import static org.vitrivr.cineast.api.rest.handlers.actions.metadata.FindObjectMetadataFullyQualifiedGetHandler.KEY_NAME;
+import static org.vitrivr.cineast.api.util.APIConstants.KEY_NAME;
 
 import io.javalin.http.Context;
 import io.javalin.plugin.openapi.dsl.OpenApiBuilder;