Merge pull request #292 from AlexanderBielen/issue-244/clear-cache-on-provider-update

Clear cache on provider update

src/main/java/org/parabot/core/Configuration.java

@@ -11,8 +11,10 @@ public class Configuration extends org.parabot.api.Configuration {
     public static final String LOGIN_SERVER             = "http://bdn.parabot.org/api/v2/users/login";
     public static final String GET_SCRIPTS              = "http://bdn.parabot.org/api/get.php?action=scripts_scripts&server=";
     public static final String GET_SCRIPT               = "http://bdn.parabot.org/api/get.php?action=scripts_script&id=";
+    public static final String GET_SERVER_PROVIDER_TYPE = "http://v3.bdn.parabot.org/api/bot/server/type?server=%s";
     public static final String GET_SERVER_PROVIDERS     = "http://bdn.parabot.org/api/get.php?action=server_providers";
     public static final String GET_SERVER_PROVIDER      = "http://v3.bdn.parabot.org/api/bot/download/provider?nightly=%s&server=%s";
+    public static final String SERVER_PROVIDER_INFO     = "http://v3.bdn.parabot.org/api/bot/list/%s?latest=true";
     public static final String GET_SERVER_PROVIDER_INFO = "http://bdn.parabot.org/api/get.php?action=server_information&name=";
     public static final String GET_SERVER_SETTINGS      = "http://bdn.parabot.org/api/get.php?action=get_settings";
     public static final String GET_BOT_VERSION          = "http://bdn.parabot.org/api/v2/bot/version";

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

@@ -166,6 +166,7 @@ public class ServerProviderInfo {
 
     /**
      * Gets the URL to download the Randoms JAR from.
+     *
      * @return The provided URL in the server config JSON (denoted by 'randoms:') or, fallback to the default BDN URL.
      */
     public URL getRandoms() {
@@ -182,4 +183,19 @@ public class ServerProviderInfo {
         // Will never return null, unless the BDN URL is changed. It shouldn't be.
         return null;
     }
+
+    /**
+     * Gets the current provider version
+     *
+     * @return provider version
+     */
+    public String getProviderVersion() {
+        String providerType = WebUtil.getJsonValue(String.format(Configuration.GET_SERVER_PROVIDER_TYPE , properties.getProperty("name")), "type");
+        if(providerType != null) {
+            String providerInfo = String.format(Configuration.SERVER_PROVIDER_INFO, providerType);
+            return WebUtil.getJsonValue(providerInfo, "version");
+        }
+
+        return null;
+    }
 }

src/main/java/org/parabot/environment/api/utils/FileUtil.java

@@ -1,10 +1,8 @@
 package org.parabot.environment.api.utils;
 
-import java.io.File;
+import java.io.*;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.IOException;
 import java.nio.channels.FileChannel;
+import java.nio.file.Files;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 
@@ -88,4 +86,29 @@ public class FileUtil {
         }
         destination.close();
     }
+
+    /**
+     * Reads the contents of a text file
+     *
+     * @param file file to get contents from
+     * @return file contents
+     * @throws IOException when anything goes wrong
+     */
+    public static String getFileContents(File file) throws IOException {
+        return new String(Files.readAllBytes(file.toPath()));
+    }
+
+    /**
+     * Writes a string to a file overwriting the existing contents if present
+     *
+     * @param file file to write to
+     * @param contents contents to write to given file
+     * @throws IOException when anything goes wrong
+     */
+    public static void writeFileContents(File file, String contents) throws IOException {
+        BufferedWriter writer = new BufferedWriter(new FileWriter(file.getAbsolutePath()));
+        writer.write(contents);
+
+        writer.close();
+    }
 }

src/main/java/org/parabot/environment/api/utils/PBLocalPreferences.java

@@ -0,0 +1,118 @@
+package org.parabot.environment.api.utils;
+
+import org.json.simple.JSONObject;
+import org.json.simple.parser.JSONParser;
+import org.parabot.core.Directories;
+
+import java.io.File;
+import java.util.HashMap;
+
+/**
+ * Manages preferences in a local file in JSON format in the Parabot settings folder
+ *
+ * @author AlexanderBielen
+ */
+public class PBLocalPreferences {
+    private static JSONParser parser = new JSONParser();
+    private File settingsFile;
+
+    public PBLocalPreferences(String fileName) {
+        settingsFile = new File(Directories.getSettingsPath() + "/" + secureFileName(fileName));
+    }
+
+    /**
+     * Gets all settings inside the file
+     *
+     * @return JSONObject or null if anything went wrong
+     */
+    public JSONObject getSettings() {
+        try {
+            String stringContents = FileUtil.getFileContents(settingsFile);
+            return (JSONObject) parser.parse(stringContents);
+        } catch(Exception ex) {
+            return null;
+        }
+    }
+
+    /**
+     * Convert a HashMap to json and writes it to the file
+     *
+     * @param settings HashMap<String, String>
+     * @param append If true, append to existing settings in file
+     */
+    public void writeSettings(HashMap<String, String> settings, boolean append) {
+        JSONObject existingSettings;
+        if(append && (existingSettings = getSettings()) != null) {
+            existingSettings.putAll(settings);
+            settings = existingSettings;
+        }
+
+        try {
+            if (!settingsFile.exists()) {
+                settingsFile.createNewFile();
+            }
+            FileUtil.writeFileContents(settingsFile, new JSONObject(settings).toJSONString());
+
+        } catch (Exception ignore) {
+            ignore.printStackTrace();
+        }
+
+    }
+
+    /**
+     * Adds a setting, or overwrites it if it exists
+     *
+     * @param key key of the setting
+     * @param value value of the setting
+     */
+    public void addSetting(String key, String value) {
+        HashMap<String, String> pair = new HashMap<>();
+        pair.put(key, value);
+        writeSettings(pair, true);
+    }
+
+    /**
+     * Fetches a setting
+     *
+     * @param key key to get the value for
+     * @return value that belongs to given key or null if non-existent
+     */
+    public String getSetting(String key) {
+        if(getSettings() == null) {
+            return null;
+        }
+
+        return getSettings().get(key).toString();
+    }
+
+    /**
+     * Adjusts an existing setting
+     *
+     * @param key key to adjust the value for
+     * @param value value for the key
+     */
+    public void adjustSetting(String key, String value) {
+        addSetting(key, value);
+    }
+
+    /**
+     * Removes a setting
+     *
+     * @param key key to remove
+     */
+    public void removeSetting(String key) {
+        JSONObject json = getSettings();
+        json.remove(key);
+        writeSettings(json, false);
+    }
+
+    /**
+     * Replaces all double dots to make sure the link does not leave the settings folder
+     *
+     * @param filePath path to secure
+     * @return secured string
+     */
+    private static String secureFileName(String filePath) {
+        return filePath.replace("..", "");
+    }
+}

src/main/java/org/parabot/environment/api/utils/WebUtil.java

@@ -1,5 +1,7 @@
 package org.parabot.environment.api.utils;
 
+import org.json.simple.JSONObject;
+
 /**
  * A WebUtil class fetches data from an URL
  *
@@ -7,4 +9,27 @@ package org.parabot.environment.api.utils;
  */
 public class WebUtil extends org.parabot.api.io.WebUtil {
 
+    /**
+     * Fetches a single value from a JSON string at the given url
+     *
+     * @param url url to get the JSON string from
+     * @param key key to search for in the JSON string
+     * @return value that belongs to given key
+     */
+    public static String getJsonValue(String url, String key) {
+        try {
+            String response = WebUtil.getContents(url);
+
+            if(response.length() > 0) {
+                JSONObject jsonObject = (JSONObject) WebUtil.getJsonParser().parse(response);
+                if (jsonObject.get(key) != null) {
+                    return jsonObject.get(key).toString();
+                }
+            }
+        } 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 cacheVersionKey = "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();
+            if(providerVersion == null) {
+                providerVersion = "error";
+            }
+
+            settings = new PBLocalPreferences(serverProviderInfo.getClientCRC32()+".json");
+            if(settings.getSetting(cacheVersionKey) != null) {
+                Core.verbose(String.format("Latest provider version: %s, local provider version: %s", settings.getSetting(cacheVersionKey), providerVersion));
+                if(!settings.getSetting(cacheVersionKey).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(cacheVersionKey, providerVersion);
+
             if (destination.exists()) {
                 Core.verbose("Found cached server provider [CRC32: " + serverProviderInfo.getCRC32() + "]");
             } else {