#933 Add MySQL to SQLite converter

- Create common parent for converting from one datasource type to another
- Add MySQL to SQLite child
- Create tests

src/main/java/fr/xephi/authme/command/CommandInitializer.java

@@ -282,7 +282,7 @@ public class CommandInitializer {
             .description("Converter command")
             .detailedDescription("Converter command for AuthMeReloaded.")
             .withArgument("job", "Conversion job: xauth / crazylogin / rakamak / " +
-                "royalauth / vauth / sqlitetosql", false)
+                "royalauth / vauth / sqliteToSql / mysqlToSqlite", false)
             .permission(AdminPermission.CONVERTER)
             .executableCommand(ConverterCommand.class)
             .build();

src/main/java/fr/xephi/authme/command/executable/authme/ConverterCommand.java

@@ -7,6 +7,7 @@ import fr.xephi.authme.command.CommandService;
 import fr.xephi.authme.command.ExecutableCommand;
 import fr.xephi.authme.converter.Converter;
 import fr.xephi.authme.converter.CrazyLoginConverter;
+import fr.xephi.authme.converter.MySqlToSqlite;
 import fr.xephi.authme.converter.RakamakConverter;
 import fr.xephi.authme.converter.RoyalAuthConverter;
 import fr.xephi.authme.converter.SqliteToSql;
@@ -55,13 +56,14 @@ public class ConverterCommand implements ExecutableCommand {
                 try {
                     converter.execute(sender);
                 } catch (Exception e) {
+                    commandService.send(sender, MessageKey.ERROR);
                     ConsoleLogger.logException("Error during conversion:", e);
                 }
             }
         });
 
         // Show a status message
-        sender.sendMessage("[AuthMe] Successfully converted from " + jobType.getName());
+        sender.sendMessage("[AuthMe] Successfully started " + jobType.getName());
     }
 
     @VisibleForTesting
@@ -71,7 +73,8 @@ public class ConverterCommand implements ExecutableCommand {
         RAKAMAK("rakamak", RakamakConverter.class),
         ROYALAUTH("royalauth", RoyalAuthConverter.class),
         VAUTH("vauth", vAuthConverter.class),
-        SQLITETOSQL("sqlitetosql", SqliteToSql.class);
+        SQLITE_TO_SQL("sqlitetosql", SqliteToSql.class),
+        MYSQL_TO_SQLITE("mysqltosqlite", MySqlToSqlite.class);
 
         private final String name;
         private final Class<? extends Converter> converterClass;

src/main/java/fr/xephi/authme/converter/AbstractDataSourceConverter.java

@@ -0,0 +1,90 @@
+package fr.xephi.authme.converter;
+
+import fr.xephi.authme.ConsoleLogger;
+import fr.xephi.authme.cache.auth.PlayerAuth;
+import fr.xephi.authme.datasource.DataSource;
+import fr.xephi.authme.datasource.DataSourceType;
+import fr.xephi.authme.util.StringUtils;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.ConsoleCommandSender;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Converts from one AuthMe data source type to another.
+ *
+ * @param <S> the source type to convert from
+ */
+public abstract class AbstractDataSourceConverter<S extends DataSource> implements Converter {
+
+    private DataSource destination;
+    private DataSourceType destinationType;
+
+    /**
+     * Constructor.
+     *
+     * @param destination the data source to convert to
+     * @param destinationType the data source type of the destination. The given data source is checked that its
+     *                        type corresponds to this type before the conversion is started, enabling us to just pass
+     *                        the current data source and letting this class check that the types correspond.
+     */
+    public AbstractDataSourceConverter(DataSource destination, DataSourceType destinationType) {
+        this.destination = destination;
+        this.destinationType = destinationType;
+    }
+
+    // Implementation note: Because of ForceFlatToSqlite it is possible that the CommandSender is null,
+    // which is never the case when a converter is launched from the /authme converter command.
+    @Override
+    public void execute(CommandSender sender) {
+        if (!destinationType.equals(destination.getType())) {
+            if (sender != null) {
+                sender.sendMessage("Please configure your connection to "
+                    + destinationType + " and re-run this command");
+            }
+            return;
+        }
+
+        S source;
+        try {
+            source = getSource();
+        } catch (Exception e) {
+            logAndSendMessage(sender, "The data source to convert from could not be initialized");
+            ConsoleLogger.logException("Could not initialize source:", e);
+            return;
+        }
+
+        List<String> skippedPlayers = new ArrayList<>();
+        for (PlayerAuth auth : source.getAllAuths()) {
+            if (destination.isAuthAvailable(auth.getNickname())) {
+                skippedPlayers.add(auth.getNickname());
+            } else {
+                destination.saveAuth(auth);
+                destination.updateQuitLoc(auth);
+            }
+        }
+
+        if (!skippedPlayers.isEmpty()) {
+            logAndSendMessage(sender, "Skipped conversion for players which were already in "
+                + destinationType + ": " + StringUtils.join(", ", skippedPlayers));
+        }
+        logAndSendMessage(sender, "Database successfully converted from " + source.getType()
+            + " to " + destinationType);
+    }
+
+    /**
+     * @return the data source to convert from
+     * @throws Exception during initialization of source
+     */
+    protected abstract S getSource() throws Exception;
+
+    private static void logAndSendMessage(CommandSender sender, String message) {
+        ConsoleLogger.info(message);
+        // Make sure sender is not console user, which will see the message from ConsoleLogger already
+        if (sender != null && !(sender instanceof ConsoleCommandSender)) {
+            sender.sendMessage(message);
+        }
+    }
+
+}

src/main/java/fr/xephi/authme/converter/ForceFlatToSqlite.java

@@ -1,21 +1,14 @@
 package fr.xephi.authme.converter;
 
-import fr.xephi.authme.ConsoleLogger;
-import fr.xephi.authme.cache.auth.PlayerAuth;
 import fr.xephi.authme.datasource.DataSource;
 import fr.xephi.authme.datasource.FlatFile;
-import fr.xephi.authme.util.StringUtils;
-
-import java.util.ArrayList;
-import java.util.List;
 
 /**
  * Mandatory migration from the deprecated flat file datasource to SQLite.
  */
-public class ForceFlatToSqlite {
+public class ForceFlatToSqlite extends AbstractDataSourceConverter<FlatFile> {
 
-    private final DataSource source;
-    private final DataSource destination;
+    private final FlatFile source;
 
     /**
      * Constructor.
@@ -24,29 +17,12 @@ public class ForceFlatToSqlite {
      * @param destination The datasource to copy the data to (sqlite)
      */
     public ForceFlatToSqlite(FlatFile source, DataSource destination) {
+        super(destination, destination.getType());
         this.source = source;
-        this.destination = destination;
     }
 
-    /**
-     * Perform the conversion.
-     */
-    public void run() {
-        List<String> skippedPlayers = new ArrayList<>();
-        for (PlayerAuth auth : source.getAllAuths()) {
-            if (destination.isAuthAvailable(auth.getNickname())) {
-                skippedPlayers.add(auth.getNickname());
-            } else {
-                destination.saveAuth(auth);
-                destination.updateQuitLoc(auth);
-            }
-        }
-
-        if (!skippedPlayers.isEmpty()) {
-            ConsoleLogger.warning("Warning: skipped conversion for players which were already in SQLite: "
-                + StringUtils.join(", ", skippedPlayers));
-        }
-        ConsoleLogger.info("Database successfully converted from " + source.getClass().getSimpleName()
-            + " to " + destination.getClass().getSimpleName());
+    @Override
+    public FlatFile getSource() {
+        return source;
     }
 }

src/main/java/fr/xephi/authme/converter/MySqlToSqlite.java

@@ -0,0 +1,28 @@
+package fr.xephi.authme.converter;
+
+import fr.xephi.authme.datasource.DataSource;
+import fr.xephi.authme.datasource.DataSourceType;
+import fr.xephi.authme.datasource.MySQL;
+import fr.xephi.authme.settings.Settings;
+
+import javax.inject.Inject;
+import java.sql.SQLException;
+
+/**
+ * Converts from MySQL to SQLite.
+ */
+public class MySqlToSqlite extends AbstractDataSourceConverter<MySQL> {
+
+    private final Settings settings;
+
+    @Inject
+    MySqlToSqlite(DataSource dataSource, Settings settings) {
+        super(dataSource, DataSourceType.SQLITE);
+        this.settings = settings;
+    }
+
+    @Override
+    protected MySQL getSource() throws SQLException, ClassNotFoundException {
+        return new MySQL(settings);
+    }
+}

src/main/java/fr/xephi/authme/converter/SqliteToSql.java

@@ -1,45 +1,28 @@
 package fr.xephi.authme.converter;
 
-import fr.xephi.authme.ConsoleLogger;
-import fr.xephi.authme.cache.auth.PlayerAuth;
 import fr.xephi.authme.datasource.DataSource;
 import fr.xephi.authme.datasource.DataSourceType;
 import fr.xephi.authme.datasource.SQLite;
-import fr.xephi.authme.output.MessageKey;
-import fr.xephi.authme.output.Messages;
 import fr.xephi.authme.settings.Settings;
-import org.bukkit.command.CommandSender;
 
 import javax.inject.Inject;
+import java.sql.SQLException;
 
-public class SqliteToSql implements Converter {
+/**
+ * Converts from SQLite to MySQL.
+ */
+public class SqliteToSql extends AbstractDataSourceConverter<SQLite> {
 
     private final Settings settings;
-    private final DataSource dataSource;
-    private final Messages messages;
 
     @Inject
-    SqliteToSql(Settings settings, DataSource dataSource, Messages messages) {
+    SqliteToSql(Settings settings, DataSource dataSource) {
+        super(dataSource, DataSourceType.MYSQL);
         this.settings = settings;
-        this.dataSource = dataSource;
-        this.messages = messages;
     }
 
     @Override
-    public void execute(CommandSender sender) {
-        if (dataSource.getType() != DataSourceType.MYSQL) {
-            sender.sendMessage("Please configure your mySQL connection and re-run this command");
-            return;
-        }
-        try {
-            SQLite data = new SQLite(settings);
-            for (PlayerAuth auth : data.getAllAuths()) {
-                dataSource.saveAuth(auth);
-            }
-        } catch (Exception e) {
-            messages.send(sender, MessageKey.ERROR);
-            ConsoleLogger.logException("Problem during SQLite to SQL conversion:", e);
-        }
+    protected SQLite getSource() throws SQLException, ClassNotFoundException {
+        return new SQLite(settings);
     }
-
 }

src/main/java/fr/xephi/authme/util/MigrationService.java

@@ -69,7 +69,7 @@ public final class MigrationService {
             try {
                 SQLite sqlite = new SQLite(settings);
                 ForceFlatToSqlite converter = new ForceFlatToSqlite(flatFile, sqlite);
-                converter.run();
+                converter.execute(null);
                 settings.setProperty(DatabaseSettings.BACKEND, DataSourceType.SQLITE);
                 settings.save();
                 return sqlite;