api method to export opml (#64)

src/main/java/com/commafeed/backend/feeds/OPMLExporter.java

@@ -0,0 +1,87 @@
+package com.commafeed.backend.feeds;
+
+import java.util.Calendar;
+import java.util.List;
+
+import javax.ejb.Stateless;
+import javax.inject.Inject;
+
+import com.commafeed.backend.dao.FeedCategoryDAO;
+import com.commafeed.backend.dao.FeedSubscriptionDAO;
+import com.commafeed.backend.model.FeedCategory;
+import com.commafeed.backend.model.FeedSubscription;
+import com.commafeed.backend.model.User;
+import com.sun.syndication.feed.opml.Attribute;
+import com.sun.syndication.feed.opml.Opml;
+import com.sun.syndication.feed.opml.Outline;
+
+@Stateless
+public class OPMLExporter {
+
+	@Inject
+	FeedCategoryDAO feedCategoryDAO;
+
+	@Inject
+	FeedSubscriptionDAO feedSubscriptionDAO;
+
+	@SuppressWarnings("unchecked")
+	public Opml export(User user) {
+		Opml opml = new Opml();
+		opml.setFeedType("opml_1.0");
+		opml.setTitle(String.format("%s subscriptions in CommaFeed",
+				user.getName()));
+		opml.setCreated(Calendar.getInstance().getTime());
+
+		List<FeedCategory> categories = feedCategoryDAO.findAll(user);
+		List<FeedSubscription> subscriptions = feedSubscriptionDAO
+				.findAll(user);
+
+		for (FeedCategory cat : categories) {
+			opml.getOutlines().add(buildCategoryOutline(cat, subscriptions));
+		}
+		for (FeedSubscription sub : subscriptions) {
+			if (sub.getCategory() == null) {
+				opml.getOutlines().add(buildSubscriptionOutline(sub));
+			}
+		}
+
+		return opml;
+
+	}
+
+	@SuppressWarnings("unchecked")
+	private Outline buildCategoryOutline(FeedCategory cat,
+			List<FeedSubscription> subscriptions) {
+		Outline outline = new Outline();
+		outline.setText(cat.getName());
+		outline.setTitle(cat.getName());
+
+		for (FeedCategory child : cat.getChildren()) {
+			outline.getChildren().add(
+					buildCategoryOutline(child, subscriptions));
+		}
+
+		for (FeedSubscription sub : subscriptions) {
+			if (sub.getCategory() != null
+					&& sub.getCategory().getId().equals(cat.getId())) {
+				outline.getChildren().add(buildSubscriptionOutline(sub));
+			}
+		}
+		return outline;
+	}
+
+	@SuppressWarnings("unchecked")
+	private Outline buildSubscriptionOutline(FeedSubscription sub) {
+		Outline outline = new Outline();
+		outline.setText(sub.getTitle());
+		outline.setTitle(sub.getTitle());
+		outline.setType("rss");
+		outline.getAttributes().add(
+				new Attribute("xmlUrl", sub.getFeed().getUrl()));
+		if (sub.getFeed().getLink() != null) {
+			outline.getAttributes().add(
+					new Attribute("htmlUrl", sub.getFeed().getLink()));
+		}
+		return outline;
+	}
+}

src/main/java/com/commafeed/frontend/rest/resources/AbstractREST.java

@@ -36,6 +36,7 @@ import com.commafeed.backend.dao.UserRoleDAO;
 import com.commafeed.backend.dao.UserSettingsDAO;
 import com.commafeed.backend.feeds.FeedFetcher;
 import com.commafeed.backend.feeds.FeedRefreshTaskGiver;
+import com.commafeed.backend.feeds.OPMLExporter;
 import com.commafeed.backend.feeds.OPMLImporter;
 import com.commafeed.backend.model.User;
 import com.commafeed.backend.model.UserRole.Role;
@@ -96,6 +97,9 @@ public abstract class AbstractREST {
 
 	@Inject
 	OPMLImporter opmlImporter;
+	
+	@Inject
+	OPMLExporter opmlExporter;
 
 	@Inject
 	PasswordEncryptionService encryptionService;

src/main/java/com/commafeed/frontend/rest/resources/FeedREST.java

@@ -9,6 +9,7 @@ import javax.ws.rs.DefaultValue;
 import javax.ws.rs.GET;
 import javax.ws.rs.POST;
 import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
 import javax.ws.rs.QueryParam;
 import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.core.MediaType;
@@ -36,6 +37,8 @@ import com.commafeed.frontend.model.request.RenameRequest;
 import com.commafeed.frontend.model.request.SubscribeRequest;
 import com.commafeed.frontend.rest.Enums.ReadType;
 import com.google.common.base.Preconditions;
+import com.sun.syndication.feed.opml.Opml;
+import com.sun.syndication.io.WireFeedOutput;
 import com.wordnik.swagger.annotations.Api;
 import com.wordnik.swagger.annotations.ApiOperation;
 import com.wordnik.swagger.annotations.ApiParam;
@@ -203,7 +206,7 @@ public class FeedREST extends AbstractResourceREST {
 	@POST
 	@Path("/import")
 	@Consumes(MediaType.MULTIPART_FORM_DATA)
-	@ApiOperation(value = "OPML Import", notes = "Import an OPML file, posted as a FORM with the 'file' name")
+	@ApiOperation(value = "OPML import", notes = "Import an OPML file, posted as a FORM with the 'file' name")
 	public Response importOpml() {
 		try {
 			FileItemFactory factory = new DiskFileItemFactory(1000000, null);
@@ -223,4 +226,21 @@ public class FeedREST extends AbstractResourceREST {
 		return Response.ok(Status.OK).build();
 	}
 
+	@GET
+	@Path("/export")
+	@Produces(MediaType.APPLICATION_XML)
+	@ApiOperation(value = "OPML export", notes = "Export an OPML file of the user's subscriptions")
+	public Response exportOpml() {
+		Opml opml = opmlExporter.export(getUser());
+		WireFeedOutput output = new WireFeedOutput();
+		String opmlString = null;
+		try {
+			opmlString = output.outputString(opml);
+		} catch (Exception e) {
+			return Response.status(Status.INTERNAL_SERVER_ERROR).entity(e)
+					.build();
+		}
+		return Response.ok(opmlString).build();
+	}
+
 }