subscribe by url callback and subtome support

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

@@ -1,6 +1,7 @@
 package com.commafeed.frontend.rest.resources;
 
 import java.io.StringWriter;
+import java.net.URI;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.List;
@@ -229,6 +230,29 @@ public class FeedREST extends AbstractResourceREST {
 		return Response.ok(Status.OK).build();
 	}
 
+	@GET
+	@Path("/subscribe")
+	@ApiOperation(value = "Subscribe to a feed", notes = "Subscribe to a feed")
+	public Response subscribe(
+			@ApiParam(value = "feed url", required = true) @QueryParam("url") String url) {
+
+		try {
+			Preconditions.checkNotNull(url);
+
+			url = prependHttp(url);
+			url = ((FeedInfo) fetchFeed(url).getEntity()).getUrl();
+
+			FeedInfo info = (FeedInfo) fetchFeed(url).getEntity();
+			feedSubscriptionService.subscribe(getUser(), info.getUrl(),
+					info.getTitle(), null);
+		} catch (Exception e) {
+			log.info("Could not subscribe to url {} : {}", url, e.getMessage());
+		}
+		return Response.temporaryRedirect(
+				URI.create(applicationSettingsService.get().getPublicUrl()))
+				.build();
+	}
+
 	private String prependHttp(String url) {
 		if (!url.startsWith("http")) {
 			url = "http://" + url;