Aggregation queries support #266

link-rest-sencha/src/main/java/com/nhl/link/rest/sencha/SenchaEncoderService.java

@@ -3,7 +3,12 @@
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.nhl.link.rest.EntityProperty;
 import com.nhl.link.rest.ResourceEntity;
-import com.nhl.link.rest.encoder.*;
+import com.nhl.link.rest.encoder.CollectionEncoder;
+import com.nhl.link.rest.encoder.DataResponseEncoder;
+import com.nhl.link.rest.encoder.Encoder;
+import com.nhl.link.rest.encoder.EncoderFilter;
+import com.nhl.link.rest.encoder.GenericEncoder;
+import com.nhl.link.rest.encoder.PropertyMetadataEncoder;
 import com.nhl.link.rest.meta.LrRelationship;
 import com.nhl.link.rest.runtime.encoder.EncoderService;
 import com.nhl.link.rest.runtime.encoder.IAttributeEncoderFactory;
@@ -28,8 +33,7 @@ public SenchaEncoderService(@Inject List<EncoderFilter> filters,
 	}
 
 	@Override
-	public <T> Encoder dataEncoder(ResourceEntity<T> entity) {
-		CollectionEncoder resultEncoder = resultEncoder(entity);
+	protected DataResponseEncoder toDataResponseEncoder(CollectionEncoder resultEncoder) {
 		return new DataResponseEncoder("data", resultEncoder, "total", GenericEncoder.encoder()) {
 			@Override
 			protected void encodeObjectBody(Object object, JsonGenerator out) throws IOException {

link-rest-sencha/src/test/java/com/nhl/link/rest/sencha/SenchaEncoderServiceTest.java

@@ -98,6 +98,7 @@ public boolean willEncode(String propertyName, Object object, Encoder delegate)
 
         ResourceEntity<E2> e2Descriptor = getResourceEntity(E2.class);
         e2Descriptor.includeId();
+        e2Descriptor.setIncoming(metadataService.getLrRelationship(E3.class, E3.E2.getName()));
 
         ResourceEntity<E3> e3Descriptor = getResourceEntity(E3.class);
         e3Descriptor.includeId();

link-rest/src/main/java/com/nhl/link/rest/AggregationType.java

@@ -0,0 +1,22 @@
+package com.nhl.link.rest;
+
+public enum AggregationType {
+
+    AVERAGE("avg"),
+
+    SUM("sum"),
+
+    MINIMUM("min"),
+
+    MAXIMUM("max");
+
+    private String functionName;
+
+    AggregationType(String functionName) {
+        this.functionName = functionName;
+    }
+
+    public String functionName() {
+        return functionName;
+    }
+}

link-rest/src/main/java/com/nhl/link/rest/ResourceEntity.java

@@ -27,15 +27,19 @@
 public class ResourceEntity<T> {
 
     private boolean idIncluded;
+    private boolean countIncluded;
 
     private LrEntity<T> lrEntity;
     private Map<String, LrAttribute> attributes;
     private Collection<String> defaultProperties;
 
+    private Map<AggregationType, List<LrAttribute>> aggregatedAttributes;
+
     private String applicationBase;
     private String mapByPath;
     private ResourceEntity<?> mapBy;
     private Map<String, ResourceEntity<?>> children;
+    private Map<String, ResourceEntity<?>> aggregateChildren;
     private LrRelationship incoming;
     private List<Ordering> orderings;
     private Expression qualifier;
@@ -48,7 +52,9 @@ public ResourceEntity(LrEntity<T> lrEntity) {
         this.idIncluded = false;
         this.attributes = new HashMap<>();
         this.defaultProperties = new HashSet<>();
+        this.aggregatedAttributes = new HashMap<>();
         this.children = new HashMap<>();
+        this.aggregateChildren = new HashMap<>();
         this.orderings = new ArrayList<>(2);
         this.extraProperties = new HashMap<>();
         this.lrEntity = lrEntity;
@@ -70,6 +76,10 @@ public LrRelationship getIncoming() {
         return incoming;
     }
 
+    public void setIncoming(LrRelationship incoming) {
+        this.incoming = incoming;
+    }
+
     public Expression getQualifier() {
         return qualifier;
     }
@@ -128,6 +138,10 @@ public ResourceEntity<?> getChild(String name) {
         return children.get(name);
     }
 
+    public Map<String, ResourceEntity<?>> getAggregateChildren() {
+        return aggregateChildren;
+    }
+
     public Map<String, EntityProperty> getExtraProperties() {
         return extraProperties;
     }
@@ -238,4 +252,30 @@ public boolean isFiltered() {
     public void setFiltered(boolean filtered) {
         this.filtered = filtered;
     }
+
+    public void includeCount() {
+        this.countIncluded = true;
+    }
+
+    public boolean isCountIncluded() {
+        return countIncluded;
+    }
+
+    public List<LrAttribute> getAggregatedAttributes(AggregationType aggregationType) {
+        return aggregatedAttributes.computeIfAbsent(aggregationType, it -> new ArrayList<>());
+    }
+
+    public boolean isAggregate() {
+        if (countIncluded) {
+            return true;
+        }
+
+        for (Collection<LrAttribute> attributes : aggregatedAttributes.values()) {
+            if (attributes.size() > 0) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }