Add command line option to fetch updates and exit afterwards

Author: Nakaner

src/main/java/de/komoot/photon/App.java

@@ -64,6 +64,18 @@ public static void main(String[] rawArgs) throws Exception {
                 return;
             }
 
+            if (args.isNominatimUpdate()) {
+                shutdownES = true;
+                log.info("Ensuring that the cluster is ready, this might take some time.");
+		// inspired by https://stackoverflow.com/a/50316299
+                esClient.admin().cluster().prepareHealth().setWaitForGreenStatus().execute().actionGet();
+                final NominatimUpdater nominatimUpdater = setupNominatimUpdater(args, esClient);
+                Thread updateThread = new Thread(() -> nominatimUpdater.update());
+		updateThread.start();
+		updateThread.join();
+                return;
+            }
+
             // no special action specified -> normal mode: start search API
             startApi(args, esClient);
         } finally {
@@ -130,6 +142,18 @@ private static void startNominatimImport(CommandLineArgs args, Server esServer,
         log.info("imported data from nominatim to photon with languages: " + args.getLanguages());
     }
 
+    /**
+     * Prepare Nominatim updater
+     *
+     * @param args
+     * @param esNodeClient
+     */
+    private static NominatimUpdater setupNominatimUpdater(CommandLineArgs args, Client esNodeClient) {
+        NominatimUpdater nominatimUpdater = new NominatimUpdater(args.getHost(), args.getPort(), args.getDatabase(), args.getUser(), args.getPassword());
+        Updater updater = new de.komoot.photon.elasticsearch.Updater(esNodeClient, args.getLanguages());
+        nominatimUpdater.setUpdater(updater);
+	return nominatimUpdater;
+    }
 
     /**
      * start api to accept search requests via http
@@ -157,10 +181,7 @@ private static void startApi(CommandLineArgs args, Client esNodeClient) {
         get("reverse/", new ReverseSearchRequestHandler("reverse/", esNodeClient, args.getLanguages()));
 
         // setup update API
-        final NominatimUpdater nominatimUpdater = new NominatimUpdater(args.getHost(), args.getPort(), args.getDatabase(), args.getUser(), args.getPassword());
-        Updater updater = new de.komoot.photon.elasticsearch.Updater(esNodeClient, args.getLanguages());
-        nominatimUpdater.setUpdater(updater);
-
+        final NominatimUpdater nominatimUpdater = setupNominatimUpdater(args, esNodeClient);
         get("/nominatim-update", (Request request, Response response) -> {
             new Thread(() -> nominatimUpdater.update()).start();
             return "nominatim update started (more information in console output) ...";

src/main/java/de/komoot/photon/CommandLineArgs.java

@@ -20,6 +20,9 @@ public class CommandLineArgs {
     @Parameter(names = "-nominatim-import", description = "import nominatim database into photon (this will delete previous index)")
     private boolean nominatimImport = false;
 
+    @Parameter(names = "-nominatim-update", description = "fetch updates from nominatim database into photon and exit (this updates the index only without offering an API")
+    private boolean nominatimUpdate = false;
+
     @Parameter(names = "-languages", description = "languages nominatim importer should import and use at run-time, comma separated (default is 'en,fr,de,it')")
     private String languages = "en,fr,de,it";