Implement remote filters to fetch only CalDAV resources with useful components (VEVENT for now)

app/src/main/java/at/bitfire/davdroid/resource/CalDavCalendar.java

@@ -8,15 +8,30 @@
 package at.bitfire.davdroid.resource;
 
 import android.accounts.Account;
+import android.util.Log;
 
 import org.apache.http.impl.client.CloseableHttpClient;
+import org.simpleframework.xml.Serializer;
+import org.simpleframework.xml.core.Persister;
 
+import java.io.StringWriter;
 import java.net.URISyntaxException;
 
 import at.bitfire.davdroid.syncadapter.AccountSettings;
+import at.bitfire.davdroid.webdav.DavCalendarQuery;
+import at.bitfire.davdroid.webdav.DavCompFilter;
+import at.bitfire.davdroid.webdav.DavFilter;
 import at.bitfire.davdroid.webdav.DavMultiget;
+import at.bitfire.davdroid.webdav.DavProp;
 
 public class CalDavCalendar extends RemoteCollection<Event> {
+	private final static String TAG = "davdroid.CalDAVCalendar";
+
+	public CalDavCalendar(CloseableHttpClient httpClient, String baseURL, String user, String password, boolean preemptiveAuth) throws URISyntaxException {
+		super(httpClient, baseURL, user, password, preemptiveAuth);
+
+	}
+
 
 	@Override
 	protected String memberAcceptedMimeTypes()
@@ -35,7 +50,33 @@ public class CalDavCalendar extends RemoteCollection<Event> {
 	}
 	
 	
-	public CalDavCalendar(CloseableHttpClient httpClient, String baseURL, String user, String password, boolean preemptiveAuth) throws URISyntaxException {
+	@Override
-		super(httpClient, baseURL, user, password, preemptiveAuth);
+	public String getMemberETagsQuery() {
+		DavCalendarQuery query = new DavCalendarQuery();
+
+		// prop
+		DavProp prop = new DavProp();
+		prop.setGetetag(new DavProp.GetETag());
+		query.setProp(prop);
+
+		// filter
+		DavFilter filter = new DavFilter();
+		query.setFilter(filter);
+
+		DavCompFilter compFilter = new DavCompFilter("VCALENDAR");
+		filter.setCompFilter(compFilter);
+
+		compFilter.setCompFilter(new DavCompFilter("VEVENT"));
+
+		Serializer serializer = new Persister();
+		StringWriter writer = new StringWriter();
+		try {
+			serializer.write(query, writer);
+		} catch (Exception e) {
+			Log.e(TAG, "Couldn't prepare REPORT query", e);
+			return null;
+		}
+
+		return writer.toString();
 	}
 }

app/src/main/java/at/bitfire/davdroid/resource/RemoteCollection.java

@@ -26,7 +26,9 @@ import java.util.List;
 
 import at.bitfire.davdroid.URIUtils;
 import at.bitfire.davdroid.syncadapter.AccountSettings;
+import at.bitfire.davdroid.webdav.DavCalendarQuery;
 import at.bitfire.davdroid.webdav.DavException;
+import at.bitfire.davdroid.webdav.DavFilter;
 import at.bitfire.davdroid.webdav.DavMultiget;
 import at.bitfire.davdroid.webdav.DavNoContentException;
 import at.bitfire.davdroid.webdav.HttpException;
@@ -36,6 +38,7 @@ import at.bitfire.davdroid.webdav.WebDavResource.PutMode;
 import ezvcard.io.text.VCardParseException;
 import lombok.Cleanup;
 import lombok.Getter;
+import lombok.Setter;
 
 /**
  * Represents a remotely stored synchronizable collection (collection as in
@@ -75,7 +78,27 @@ public abstract class RemoteCollection<T extends Resource> {
 		return collection.getCTag();
 	}
 
+
+	/**
+	 * Returns a body for the REPORT request that queries all members of the collection
+	 * that should be considered. Allows collections to implement remote filters.
+	 * @return  body for REPORT request or null if PROPFIND shall be used
+	 */
+	public String getMemberETagsQuery() {
+		return null;
+	}
+
+	/**
+	 * Gets the ETags of the resources in a collection. If davQuery is set, it's required to be a
+	 * complete addressbook-query or calendar-query XML and will cause getMemberETags() to use REPORT
+	 * instead of PROPFIND.
+	 * @return  array of Resources where only the resource names and ETags are set
+	 */
 	public Resource[] getMemberETags() throws URISyntaxException, IOException, DavException, HttpException {
+		String query = getMemberETagsQuery();
+		if (query != null)
+			collection.report(query);
+		else
 			collection.propfind(HttpPropfind.Mode.MEMBERS_ETAG);
 
 		List<T> resources = new LinkedList<T>();
@@ -84,13 +107,15 @@ public abstract class RemoteCollection<T extends Resource> {
 				resources.add(newResourceSkeleton(member.getName(), member.getETag()));
 
 		return resources.toArray(new Resource[0]);
+
 	}
 
+
 	@SuppressWarnings("unchecked")
 	public Resource[] multiGet(Resource[] resources) throws URISyntaxException, IOException, DavException, HttpException {
 		try {
 			if (resources.length == 1)
-				return (T[]) new Resource[]{get(resources[0])};
+				return (T[]) new Resource[] { get(resources[0]) };
 
 			Log.i(TAG, "Multi-getting " + resources.length + " remote resource(s)");
 

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarsSyncAdapterService.java

@@ -48,7 +48,7 @@ public class CalendarsSyncAdapterService extends Service {
 	
 
 	private static class SyncAdapter extends DavSyncAdapter {
-		private final static String TAG = "davdroid.CalendarsSyncAdapter";
+		private final static String TAG = "davdroid.CalDAVSync";
 
 		
 		private SyncAdapter(Context context) {

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncAdapterService.java

@@ -47,7 +47,7 @@ public class ContactsSyncAdapterService extends Service {
 	
 
 	private static class ContactsSyncAdapter extends DavSyncAdapter {
-		private final static String TAG = "davdroid.ContactsSyncAdapter";
+		private final static String TAG = "davdroid.CardDAVSync";
 
 		
 		private ContactsSyncAdapter(Context context) {

app/src/main/java/at/bitfire/davdroid/webdav/DavCalendarQuery.java

@@ -0,0 +1,23 @@
+package at.bitfire.davdroid.webdav;
+
+import org.simpleframework.xml.Element;
+import org.simpleframework.xml.Namespace;
+import org.simpleframework.xml.NamespaceList;
+import org.simpleframework.xml.Root;
+
+import lombok.Getter;
+import lombok.Setter;
+
+@Root(name="calendar-query")
+@NamespaceList({
+		@Namespace(reference="DAV:"),
+		@Namespace(prefix="C",reference="urn:ietf:params:xml:ns:caldav")
+})
+@Namespace(prefix="C",reference="urn:ietf:params:xml:ns:caldav")
+public class DavCalendarQuery {
+	@Element
+	@Getter	@Setter DavProp prop;
+
+	@Element
+	@Getter @Setter DavFilter filter;
+}

app/src/main/java/at/bitfire/davdroid/webdav/DavCompFilter.java

@@ -0,0 +1,23 @@
+package at.bitfire.davdroid.webdav;
+
+import org.simpleframework.xml.Attribute;
+import org.simpleframework.xml.Element;
+import org.simpleframework.xml.Namespace;
+import org.simpleframework.xml.Root;
+
+import lombok.Getter;
+import lombok.Setter;
+
+@Namespace(prefix="C",reference="urn:ietf:params:xml:ns:caldav")
+public class DavCompFilter {
+	public DavCompFilter(String name) {
+		this.name = name;
+	}
+
+	@Attribute(required=false)
+	String name;
+
+	@Element(required=false,name="comp-filter")
+	@Getter @Setter	DavCompFilter compFilter;
+
+}

app/src/main/java/at/bitfire/davdroid/webdav/DavFilter.java

@@ -0,0 +1,13 @@
+package at.bitfire.davdroid.webdav;
+
+import org.simpleframework.xml.Element;
+import org.simpleframework.xml.Namespace;
+
+import lombok.Getter;
+import lombok.Setter;
+
+@Namespace(prefix="C",reference="urn:ietf:params:xml:ns:caldav")
+public class DavFilter {
+	@Element(required=false)
+	@Getter	@Setter	DavCompFilter compFilter;
+}

app/src/main/java/at/bitfire/davdroid/webdav/DavProp.java

@@ -35,7 +35,7 @@ public class DavProp {
 	GetCTag getctag;
 	
 	@Element(required=false)
-	GetETag getetag;
+	@Setter GetETag getetag;
 	
 	@Root(strict=false)
 	public static class ResourceType {

app/src/main/java/at/bitfire/davdroid/webdav/WebDavResource.java

@@ -332,6 +332,18 @@ public class WebDavResource {
 		processMultiStatus(response);
 	}
 
+	public void report(String query) throws IOException, HttpException, DavException {
+		HttpReport report = new HttpReport(location, query);
+		report.setHeader("Depth", "1");
+
+		@Cleanup CloseableHttpResponse response = httpClient.execute(report, context);
+		if (response == null)
+			throw new DavNoContentException();
+
+		checkResponse(response);
+		processMultiStatus(response);
+	}
+
 	
 	/* resource operations */