[FEATURE] Storing provider version locally and clear cache when outdated

src/main/java/org/parabot/core/desc/ServerProviderInfo.java

@@ -182,4 +182,32 @@ public class ServerProviderInfo {
         // Will never return null, unless the BDN URL is changed. It shouldn't be.
         return null;
     }
+
+
+    /**
+     * This is a temporary method until the bdn gets updated
+     * @param serverName
+     * @return
+     */
+    public static String getProviderVersion(String serverName) {
+        try {
+            serverName = serverName.toLowerCase();
+            String providerInfo = String.format("http://v3.bdn.parabot.org/api/bot/list/%s-provider?latest=true", serverName);
+            String response = WebUtil.getContents(providerInfo);
+
+            if (response.length() > 0) {
+                JSONObject jsonObject = (JSONObject) WebUtil.getJsonParser().parse(response);
+
+                if (jsonObject.get("version") != null) {
+                    return jsonObject.get("version").toString();
+                }
+            } else if (response.equals("")) {
+                return getProviderVersion("default");
+            }
+        } catch(Exception ex) {
+            ex.printStackTrace();
+        }
+
+        return null;
+    }
 }

src/main/java/org/parabot/environment/servers/executers/PublicServerExecuter.java

@@ -11,6 +11,7 @@ import org.parabot.core.forum.AccountManager;
 import org.parabot.core.forum.AccountManagerAccess;
 import org.parabot.core.ui.components.VerboseLoader;
 import org.parabot.core.ui.utils.UILog;
+import org.parabot.environment.api.utils.PBLocalPreferences;
 import org.parabot.environment.api.utils.WebUtil;
 import org.parabot.environment.servers.ServerProvider;
 import org.parabot.environment.servers.loader.ServerLoader;
@@ -37,6 +38,9 @@ public class PublicServerExecuter extends ServerExecuter {
     };
     private String serverName;
 
+    private PBLocalPreferences settings;
+    private final String CACHE_VERSION_KEY = "cachedProviderVersion";
+
     public PublicServerExecuter(final String serverName) {
         this.serverName = serverName;
     }
@@ -53,6 +57,24 @@ public class PublicServerExecuter extends ServerExecuter {
 
             Core.verbose("Downloading: " + jarUrl + " ...");
 
+            String providerVersion = ServerProviderInfo.getProviderVersion(serverName);
+            if(providerVersion == null) {
+                providerVersion = "error";
+            }
+
+            settings = new PBLocalPreferences(serverProviderInfo.getClientCRC32()+".json");
+            if(settings.getSetting(CACHE_VERSION_KEY) != null) {
+                Core.verbose(String.format("Latest provider version: %s, local provider version: %s", settings.getSetting(CACHE_VERSION_KEY), providerVersion));
+                if(!settings.getSetting(CACHE_VERSION_KEY).equals(providerVersion)) {
+                    Core.verbose("Local provider outdated, clearing cache.");
+                    Directories.clearCache();
+                }
+            } else {
+                Core.verbose("No local provider version in settings, adding to settings file");
+            }
+
+            settings.addSetting(CACHE_VERSION_KEY, providerVersion);
+
             if (destination.exists()) {
                 Core.verbose("Found cached server provider [CRC32: " + serverProviderInfo.getCRC32() + "]");
             } else {