Add support for querying stale views

src/main/java/de/thm/arsnova/dao/NovaView.java

@@ -28,8 +28,14 @@ import com.fourspaces.couchdb.View;
 
 public class NovaView extends View {
 
+	public enum StaleMode {
+		NONE, OK, UPDATE_AFTER
+	}
+
 	protected String keys;
 
+	protected StaleMode stale = StaleMode.NONE;
+
 	public NovaView(final String fullname) {
 		super(fullname);
 	}
@@ -89,6 +95,10 @@ public class NovaView extends View {
 		this.keys = toJsonArray(keys.toArray(new String[keys.size()]));
 	}
 
+	public void setStale(StaleMode stale) {
+		this.stale = stale;
+	}
+
 	@Override
 	public String getQueryString() {
 		final String tempQuery = super.getQueryString();
@@ -102,6 +112,16 @@ public class NovaView extends View {
 			}
 			query.append("keys=" + keys);
 		}
+		if (stale != null && stale != StaleMode.NONE) {
+			if (query.length() > 0) {
+				query.append("&");
+			}
+			if (stale == StaleMode.OK) {
+				query.append("stale=ok");
+			} else if (stale == StaleMode.UPDATE_AFTER) {
+				query.append("stale=update_after");
+			}
+		}
 
 		if (query.length() == 0) {
 			return null;

src/test/java/de/thm/arsnova/dao/NovaViewTest.java

@@ -18,8 +18,7 @@
  */
 package de.thm.arsnova.dao;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
+import static org.junit.Assert.*;
 
 import java.io.UnsupportedEncodingException;
 import java.net.URLEncoder;
@@ -27,6 +26,8 @@ import java.util.Arrays;
 
 import org.junit.Test;
 
+import de.thm.arsnova.dao.NovaView.StaleMode;
+
 public class NovaViewTest {
 
 	@Test
@@ -133,6 +134,21 @@ public class NovaViewTest {
 		assertEncodedEquals("keys", "[]", v5.getQueryString());
 	}
 
+	@Test
+	public void shouldSupportStaleViews() {
+		final NovaView v1 = new NovaView(null);
+		final NovaView v2 = new NovaView(null);
+		final NovaView v3 = new NovaView(null);
+		final NovaView v4 = new NovaView(null);
+		v1.setStale(StaleMode.NONE);
+		v2.setStale(StaleMode.OK);
+		v3.setStale(StaleMode.UPDATE_AFTER);
+		assertNull(v1.getQueryString());
+		assertEncodedEquals("stale", "ok", v2.getQueryString());
+		assertEncodedEquals("stale", "update_after", v3.getQueryString());
+		assertNull(v4.getQueryString());
+	}
+
 	private void assertEncodedEquals(final String key, final String expected, final String actual) {
 		try {
 			assertEquals(key + "=" + URLEncoder.encode(expected, "UTF-8"), actual);