DATACOUCH-59 - Allow expiry touch on read

Configuration is based on Document annotation. When read of document takes place then touch action is executed on document. It is an asynchronous action so it does not block read. It is executed only on single reads (not view-based or N1QL-based ones).

src/integration/java/org/springframework/data/couchbase/core/CouchbaseTemplateTests.java

@@ -402,6 +402,22 @@ public class CouchbaseTemplateTests {
 		assertEquals(versionedClass.getVersion(), foundClass.getVersion());
 	}
 
+	/**
+	 * @see DATACOUCH-59
+   */
+	@Test
+	public void expiryWhenTouchOnReadDocument() throws InterruptedException {
+		String id = "simple-doc-with-update-expiry-for-read";
+		DocumentWithTouchOnRead doc = new DocumentWithTouchOnRead(id);
+		template.save(doc);
+		Thread.sleep(1500);
+		assertNotNull(template.findById(id, DocumentWithTouchOnRead.class));
+		Thread.sleep(1500);
+		assertNotNull(template.findById(id, DocumentWithTouchOnRead.class));
+		Thread.sleep(3000);
+		assertNull(template.findById(id, DocumentWithTouchOnRead.class));
+	}
+
 	/**
 	 * A sample document with just an id and property.
 	 */
@@ -433,6 +449,20 @@ public class CouchbaseTemplateTests {
 		}
 	}
 
+	/**
+	 * A sample document that expires in 2 seconds and touchOnRead set.
+	 */
+	@Document(expiry = 2, touchOnRead = true)
+	static class DocumentWithTouchOnRead {
+
+		@Id
+		private final String id;
+
+		public DocumentWithTouchOnRead(String id) {
+			this.id = id;
+		}
+	}
+
 	@Document
 	static class ComplexPerson {
 

src/main/java/org/springframework/data/couchbase/core/CouchbaseTemplate.java

@@ -281,10 +281,15 @@ public class CouchbaseTemplate implements CouchbaseOperations, ApplicationEventP
 
   @Override
   public <T> T findById(final String id, Class<T> entityClass) {
+    final CouchbasePersistentEntity<?> entity = mappingContext.getPersistentEntity(entityClass);
     RawJsonDocument result = execute(new BucketCallback<RawJsonDocument>() {
       @Override
       public RawJsonDocument doInBucket() {
-        return client.get(id, RawJsonDocument.class);
+        if (entity.isTouchOnRead()) {
+          return client.getAndTouch(id, entity.getExpiry(), RawJsonDocument.class);
+        } else {
+          return client.get(id, RawJsonDocument.class);
+        }
       }
     });
 

src/main/java/org/springframework/data/couchbase/core/mapping/BasicCouchbasePersistentEntity.java

@@ -16,12 +16,7 @@
 
 package org.springframework.data.couchbase.core.mapping;
 
-import java.util.Calendar;
-import java.util.TimeZone;
-import java.util.concurrent.TimeUnit;
-
 import com.couchbase.client.java.repository.annotation.Id;
-
 import org.springframework.beans.BeansException;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
@@ -31,6 +26,10 @@ import org.springframework.data.mapping.model.BasicPersistentEntity;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 
+import java.util.Calendar;
+import java.util.TimeZone;
+import java.util.concurrent.TimeUnit;
+
 /**
  * The representation of a persistent entity.
  *
@@ -123,4 +122,11 @@ public class BasicCouchbasePersistentEntity<T> extends BasicPersistentEntity<T,
     }
   }
 
+  @Override
+  public boolean isTouchOnRead() {
+    org.springframework.data.couchbase.core.mapping.Document annotation = getType().getAnnotation(
+        org.springframework.data.couchbase.core.mapping.Document.class);
+    return annotation == null ? false : getExpiry() > 0 && annotation.touchOnRead();
+  }
+
 }

src/main/java/org/springframework/data/couchbase/core/mapping/CouchbasePersistentEntity.java

@@ -42,4 +42,12 @@ public interface CouchbasePersistentEntity<T> extends
    */
   int getExpiry();
 
+  /**
+   * Flag for using getAndTouch operations for reads, resetting the expiration (if one was set) when the
+   * entity is directly read (eg. findOne, findById).
+   *
+   * @return true if a direct read of the document should trigger a touch, resetting its expiration timer.
+   */
+   boolean isTouchOnRead();
+
 }

src/main/java/org/springframework/data/couchbase/core/mapping/Document.java

@@ -46,4 +46,10 @@ public @interface Document {
    */
   TimeUnit expiryUnit() default TimeUnit.SECONDS;
 
+  /**
+   * An optional flag associated with {@link #expiry()} indicating whether the expiry timer should
+   * be reset whenever the document is directly read (eg. findByOne, findById).
+   */
+  boolean touchOnRead() default false;
+
 }

src/test/java/org/springframework/data/couchbase/core/mapping/BasicCouchbasePersistentEntityTests.java

@@ -17,6 +17,8 @@
 package org.springframework.data.couchbase.core.mapping;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 import java.util.Calendar;
 import java.util.Date;
@@ -103,6 +105,42 @@ public class BasicCouchbasePersistentEntityTests {
     assertEquals(expected.get(Calendar.SECOND), calendar.get(Calendar.SECOND));
   }
 
+  @Test
+  public void doesNotUseGetExpiry() throws Exception {
+    assertEquals(0, getBasicCouchbasePersistentEntity(SimpleDocument.class).getExpiry());
+  }
+
+  @Test
+  public void usesGetExpiry() throws Exception {
+    assertEquals(10, getBasicCouchbasePersistentEntity(SimpleDocumentWithExpiry.class).getExpiry());
+  }
+
+  @Test
+  public void doesNotUseIsUpdateExpiryForRead() throws Exception {
+    assertFalse(getBasicCouchbasePersistentEntity(SimpleDocument.class).isTouchOnRead());
+    assertFalse(getBasicCouchbasePersistentEntity(SimpleDocumentWithExpiry.class).isTouchOnRead());
+    }
+
+  @Test
+  public void usesTouchOnRead() throws Exception {
+    assertTrue(getBasicCouchbasePersistentEntity(SimpleDocumentWithTouchOnRead.class).isTouchOnRead());
+  }
+
+  private BasicCouchbasePersistentEntity getBasicCouchbasePersistentEntity(Class<?> clazz) {
+    return new BasicCouchbasePersistentEntity(ClassTypeInformation.from(clazz));
+  }
+
+  public static class SimpleDocument {
+  }
+
+  @Document(expiry = 10)
+  public static class SimpleDocumentWithExpiry {
+  }
+
+  @Document(expiry = 10, touchOnRead = true)
+  public static class SimpleDocumentWithTouchOnRead {
+  }
+
   /**
    * Simple POJO to test default expiry.
    */