Cacher les identifiants SQL au client ?

[robin4002]

Il faut envoyer la valeur au client avec un paquet.
Le client ne doit jamais avoir un accès directe à la base.

[Cobra45]

Par exemple, j’ai cette fonction dans ma classe SQLDatabase qui me permet de récupérer une valeur.
Comment dois-je faire pour que le client recoive la valeur ?

    public static void getValue(String table, String sectionRecover, String stringRecover, String recoverSection) {
        String returnString = null;
        try {
            Connection con = DriverManager.getConnection(urlbase + host + "/" + database, user, pass);

            Statement q = con.createStatement();
            String sql = "SELECT * FROM " + table + " WHERE " + recoverSection + " = '" + stringRecover + "'";
            ResultSet rs = q.executeQuery(sql);

            while (rs.next()) {
                returnString = rs.getString(sectionRecover);
            }

            q.close();
            con.close();

            result = returnString;
        } catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }

[robin4002]

Tu dois faire un paquet permettant au client de demander le variable et un paquet de réponse qui renvoie la variable une fois récupéré.

Par contre attention à tes variables, si le client a le contrôle sur table, recoverSection ou stringRecover tu as une grosse faille de sécurité.

[Cobra45]

J’ai essayé de faire quelque chose mais bon… je ne suis pas sûr du tout, ça ne fonctionne pas le jeu crash lorsque je fais la commande

EDIT : non en fait le jeu ne crash pas, j’ai cette erreur dans la console :

No suitable driver found for nullnull/null

Alors qu’au niveau de la connexion dans le ServerProxy ça a l’air de bien fonctionner

Classe principale

    @EventHandler
    public void preInit(FMLPreInitializationEvent event)
    {
        logger = event.getModLog();
        proxy.preInit(event.getSuggestedConfigurationFile());

        network = NetworkRegistry.INSTANCE.newSimpleChannel(MODID);
        network.registerMessage(PacketSimpleCommand.Handler.class, PacketSimpleCommand.class, 0, Side.CLIENT);
        network.registerMessage(PacketSQLGetResult.Handler.class, PacketSQLGetResult.class, 1, Side.SERVER);
    }

Commande

public class SimpleCommand extends CommandBase {

    @Override
    public String getName() {
        return "getplayerdata";
    }

    @Override
    public String getUsage(ICommandSender sender) {
        return null;
    }

    @Override
    public boolean checkPermission(MinecraftServer server, ICommandSender sender) {
        return true;
    }

    @Override
    public void execute(MinecraftServer server, ICommandSender sender, String[] args) throws CommandException {
        if(sender instanceof EntityPlayer) {
            Main.network.sendTo(new PacketSimpleCommand("getplayerdata"), (EntityPlayerMP) sender);
        }
    }
}

Packet commande

public class PacketSimpleCommand implements IMessage {

    private static String command_name;

    public PacketSimpleCommand() { }

    public PacketSimpleCommand(String command_name) {
        this.command_name = command_name;
    }

    @Override
    public void fromBytes(ByteBuf buf) {
        command_name = ByteBufUtils.readUTF8String(buf);
    }

    @Override
    public void toBytes(ByteBuf buf) {
        ByteBufUtils.writeUTF8String(buf, command_name);
    }

    public static class Handler implements IMessageHandler<PacketSimpleCommand, IMessage> {

        public SQLDatabase sql;

        @SideOnly(Side.CLIENT)
        @Override
        public IMessage onMessage(PacketSimpleCommand message, MessageContext ctx) {
            if (command_name.equals("getplayerdata")) {
                SQLDatabase.getValue("users", "grade", "" + Minecraft.getMinecraft().player.getDisplayNameString(), "pseudo");
            }
            return null;
        }
    }
}

Fonction SQL

    public static void getValue(String table, String sectionRecover, String stringRecover, String recoverSection) {
        String returnString = null;
        try {
            Connection con = DriverManager.getConnection(urlbase + host + "/" + database, user, pass);
            System.out.println("Successfully connected to database");

            Statement q = con.createStatement();
            String sql = "SELECT * FROM " + table + " WHERE " + recoverSection + " = '" + stringRecover + "'";
            ResultSet rs = q.executeQuery(sql);

            while (rs.next()) {
                returnString = rs.getString(sectionRecover);
            }

            q.close();
            con.close();

            Main.network.sendToServer(new PacketSQLGetResult(returnString));

        } catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }

Packet fonction SQL

public class PacketSQLGetResult implements IMessage {

    private static String result;

    public PacketSQLGetResult() { }

    public PacketSQLGetResult(String result) {
        this.result = result;
    }

    @Override
    public void fromBytes(ByteBuf buf) {
        result = ByteBufUtils.readUTF8String(buf);
    }

    @Override
    public void toBytes(ByteBuf buf) {
        ByteBufUtils.writeUTF8String(buf, result);
    }

    public static class Handler implements IMessageHandler<PacketSQLGetResult, IMessage> {

        @SideOnly(Side.CLIENT)
        @Override
        public IMessage onMessage(PacketSQLGetResult message, MessageContext ctx) {
            System.out.println(message.result);
            return null;
        }
    }
}

[robin4002]

Tes variables urlbase, host, + database, user et pass ne semble pas initialisé.
Impossible de savoir pourquoi avec le morceau de code que tu as envoyé.

[Cobra45]

Voici la classe complète que j’ai modifiée, et en dessous le ServerProxy + le morceau qui correspond sur la classe principale

public class SQLDatabase {

    private Connection connection;
    public static String urlbase, host, database, user, pass;
    public static String result;

    public SQLDatabase(String urlbase, String host, String database, String user, String pass){
        this.urlbase = urlbase;
        this.host = host;
        this.database = database;
        this.user = user;
        this.pass = pass;
        System.out.println("Database successfully attached");
    }

    public static void getValue(String table, String sectionRecover, String stringRecover, String recoverSection) {
        String returnString = null;
        try {
            Connection con = DriverManager.getConnection(urlbase + host + "/" + database, user, pass);
            System.out.println("Successfully connected to database");

            Statement q = con.createStatement();
            String sql = "SELECT * FROM " + table + " WHERE " + recoverSection + " = '" + stringRecover + "'";
            ResultSet rs = q.executeQuery(sql);

            while (rs.next()) {
                returnString = rs.getString(sectionRecover);
            }

            q.close();
            con.close();

            Main.network.sendToServer(new PacketSQLGetResult(returnString));

        } catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }
}

ServerProxy

public class ServerProxy extends CommonProxy
{
    public SQLDatabase sql;

    public static String host, database, user, pass;

    @Override
    public void preInit(File configFile)
    {
        super.preInit(configFile);
        System.out.println("ServerProxy loaded");
    }

    @Override
    public void init()
    {
        this.sql = new SQLDatabase("jdbc:mysql://", Main.host, Main.database, Main.user, Main.pass);
        super.init();
    }
}

Classe principale

    @SideOnly(Side.SERVER)
    @EventHandler
    public void loadConfig(FMLPreInitializationEvent event) {
        Configuration cfg = new Configuration(event.getSuggestedConfigurationFile());
        try
        {
            cfg.load();
            host = cfg.get("MySQL", "host", "").getString();
            database = cfg.get("MySQL", "database", "").getString();
            user = cfg.get("MySQL", "user", "").getString();
            pass = cfg.get("MySQL", "pass", "").getString();
            System.out.println("Configuration loaded");
        }
        catch(Exception ex)
        {
            System.out.println("Failed to load configuration");
        }
        finally
        {
            if(cfg.hasChanged())
            {
                cfg.save();
            }
        }
    }

[robin4002]

Tes variables host, database, user, pass de ta classe ServerProxy ne sont pas les mêmes que celle dans la classe principale.
Là tes variables dans le serveur proxy sont null et jamais initialisé …

Le mieux serait de charger les config en rapport avec mysql dans le serveur proxy également.

[Cobra45]

J’ai fais ceci pour le ServerProxy, ça a l’air d’être ok :

public class ServerProxy extends CommonProxy
{
    public SQLDatabase sql;

    public static String host, database, user, pass;

    public static Configuration config;
    private static String file = "config/" + Main.MODID + ".cfg";

    @Override
    public void preInit(File configFile)
    {
        super.preInit(configFile);
        System.out.println("ServerProxy loaded");

        Configuration cfg = new Configuration(new File(file));
        try
        {
            cfg.load();
            host = cfg.get("MySQL", "host", "").getString();
            database = cfg.get("MySQL", "database", "").getString();
            user = cfg.get("MySQL", "user", "").getString();
            pass = cfg.get("MySQL", "pass", "").getString();
            System.out.println("Configuration loaded");

            this.sql = new SQLDatabase("jdbc:mysql://", host, database, user, pass);
        }
        catch(Exception ex)
        {
            System.out.println("Failed to load configuration");
        }
        finally
        {
            if(cfg.hasChanged())
            {
                cfg.save();
            }
        }

    }

    @Override
    public void init()
    {
        super.init();
    }

Par contre j’ai un autre soucis maintenant, lorsque je veux print par exemple le résultat de la requête, rien n’apparait et le paquet ne marche pas. Voici la partie concernée :

    private Connection connection;
    public static String urlbase, host, database, user, pass;
    public static String result;

    public SQLDatabase(String urlbase, String host, String database, String user, String pass){
        this.urlbase = urlbase;
        this.host = host;
        this.database = database;
        this.user = user;
        this.pass = pass;
        System.out.println("Database successfully attached with : " + urlbase + " " + host + " " + database + " " + user + " " + pass);
    }

    public static void getValue(String table, String sectionRecover, String stringRecover, String recoverSection) {
        String returnString = null;
        try {
            Connection con = DriverManager.getConnection(urlbase + host + "/" + database, user, pass);
            System.out.println("Successfully connected to database");

            Statement q = con.createStatement();
            String sql = "SELECT * FROM " + table + " WHERE " + recoverSection + " = '" + stringRecover + "'";
            ResultSet rs = q.executeQuery(sql);

            while (rs.next()) {
                returnString = rs.getString(sectionRecover);
            }

            q.close();
            con.close();

            System.out.println("test");
            System.out.println(returnString);

            Main.network.sendToServer(new PacketSQLGetResult(returnString));

        } catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }

Commande

public class SimpleCommand extends CommandBase {

    @Override
    public String getName() {
        return "getplayerdata";
    }

    @Override
    public String getUsage(ICommandSender sender) {
        return null;
    }

    @Override
    public boolean checkPermission(MinecraftServer server, ICommandSender sender) {
        return true;
    }

    @Override
    public void execute(MinecraftServer server, ICommandSender sender, String[] args) throws CommandException {
        if(sender instanceof EntityPlayer) {
            Main.network.sendTo(new PacketSimpleCommand("getplayerdata"), (EntityPlayerMP) sender);
        }
    }
}

Packet de la commande

public class PacketSimpleCommand implements IMessage {

    private static String command_name;

    public PacketSimpleCommand() { }

    public PacketSimpleCommand(String command_name) {
        this.command_name = command_name;
    }

    @Override
    public void fromBytes(ByteBuf buf) {
        command_name = ByteBufUtils.readUTF8String(buf);
    }

    @Override
    public void toBytes(ByteBuf buf) {
        ByteBufUtils.writeUTF8String(buf, command_name);
    }

    public static class Handler implements IMessageHandler<PacketSimpleCommand, IMessage> {

        public SQLDatabase sql;

        @SideOnly(Side.CLIENT)
        @Override
        public IMessage onMessage(PacketSimpleCommand message, MessageContext ctx) {
            if (command_name.equals("getplayerdata")) {
                SQLDatabase.getValue("users", "grade", "" + Minecraft.getMinecraft().player.getDisplayNameString(), "pseudo");
            }
            return null;
        }
    }
}

Packet résultat SQL

public class PacketSQLGetResult implements IMessage {

    private static String result;

    public PacketSQLGetResult() { }

    public PacketSQLGetResult(String result) {
        this.result = result;
    }

    @Override
    public void fromBytes(ByteBuf buf) {
        result = ByteBufUtils.readUTF8String(buf);
    }

    @Override
    public void toBytes(ByteBuf buf) {
        ByteBufUtils.writeUTF8String(buf, result);
    }

    public static class Handler implements IMessageHandler<PacketSQLGetResult, IMessage> {

        @SideOnly(Side.CLIENT)
        @Override
        public IMessage onMessage(PacketSQLGetResult message, MessageContext ctx) {
            System.out.println(message.result);
            return null;
        }
    }
}

[robin4002]

Quand tu tapes une commande, l’exécution se fait sur le serveur.
Donc pour ce cas, il faut que tu appels la fonction sql directement dans la fonction exécute de ta commande puis que tu envoies la réponse par paquet.

[Cobra45]

J’obtiens cette erreur :

[21:19:19] [main/INFO] [minecraft/GuiNewChat]: [CHAT] Cette commande a échoué suite à une erreur inconnue

Commande :

public class SimpleCommand extends CommandBase {

    @Override
    public String getName() {
        return "getplayerdata";
    }

    @Override
    public String getUsage(ICommandSender sender) {
        return null;
    }

    @Override
    public boolean checkPermission(MinecraftServer server, ICommandSender sender) {
        return true;
    }

    @Override
    public void execute(MinecraftServer server, ICommandSender sender, String[] args) throws CommandException {
        if(sender instanceof EntityPlayer) {
            SQLDatabase.getValue("users", "grade", "" + Minecraft.getMinecraft().player.getDisplayNameString(), "pseudo");
        }
    }
}

[robin4002]

Rien d’autre dans la console ?
Si oui, mets l’appel de ta fonction getValue dans un try catch et log l’exception.

[Cobra45]

Effectivement, l’erreur contient ceci également :

[21:59:00] [Server thread/WARN] [minecraft/CommandHandler]: Couldn't process command: getplayerdata
java.lang.NoClassDefFoundError: net/minecraft/client/Minecraft
	at fr.minewarfare.commands.SimpleCommand.execute(SimpleCommand.java:35) ~[SimpleCommand.class:?]
	at net.minecraft.command.CommandHandler.tryExecute(CommandHandler.java:126) [CommandHandler.class:?]
	at net.minecraft.command.CommandHandler.executeCommand(CommandHandler.java:98) [CommandHandler.class:?]
	at net.minecraft.network.NetHandlerPlayServer.handleSlashCommand(NetHandlerPlayServer.java:1003) [NetHandlerPlayServer.class:?]
	at net.minecraft.network.NetHandlerPlayServer.processChatMessage(NetHandlerPlayServer.java:979) [NetHandlerPlayServer.class:?]
	at net.minecraft.network.play.client.CPacketChatMessage.processPacket(CPacketChatMessage.java:47) [CPacketChatMessage.class:?]
	at net.minecraft.network.play.client.CPacketChatMessage.processPacket(CPacketChatMessage.java:8) [CPacketChatMessage.class:?]
	at net.minecraft.network.PacketThreadUtil$1.run(PacketThreadUtil.java:21) [PacketThreadUtil$1.class:?]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_201]
	at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) [?:1.8.0_201]
	at java.util.concurrent.FutureTask.run(FutureTask.java) [?:1.8.0_201]
	at net.minecraft.util.Util.runTask(Util.java:53) [Util.class:?]
	at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:798) [MinecraftServer.class:?]
	at net.minecraft.server.dedicated.DedicatedServer.updateTimeLightAndEntities(DedicatedServer.java:415) [DedicatedServer.class:?]
	at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:743) [MinecraftServer.class:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:592) [MinecraftServer.class:?]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_201]
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.Minecraft
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) ~[launchwrapper-1.12.jar:?]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_201]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_201]
	... 17 more
Caused by: net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerException: Exception in class transformer net.minecraftforge.fml.common.asm.transformers.SideTransformer@59bbb974 from coremod FMLCorePlugin
	at net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerWrapper.transform(ASMTransformerWrapper.java:260) ~[forgeSrc-1.12.2-14.23.5.2768.jar:?]
	at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.12.jar:?]
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.12.jar:?]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_201]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_201]
	... 17 more
Caused by: java.lang.RuntimeException: Attempted to load class net/minecraft/client/Minecraft for invalid side SERVER
	at net.minecraftforge.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:62) ~[forgeSrc-1.12.2-14.23.5.2768.jar:?]
	at net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerWrapper.transform(ASMTransformerWrapper.java:256) ~[forgeSrc-1.12.2-14.23.5.2768.jar:?]
	at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.12.jar:?]
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.12.jar:?]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_201]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_201]
	... 17 more

[robin4002]

Ah oui, c’est à cause du Minecraft.getMinecraft().player dans ta fonction execute. Il n’est pas possible d’utiliser la classe Minecraft côté serveur.
Et dans ton cas il suffit de faire (EntityPlayer)sender pour récupérer le joueur qui a exécuté la commande.

[Cobra45]

C’est bon, j’ai une autre erreur maintenant, ça doit venir du (EntityPlayer)sender, ça doit fausser la requête SQL.
J’ai essayé avec (EntityPlayer)sender.getDisplayName() ça ne fonctionne pas non plus (ça correspond au stringRecover)

[22:18:24] [Server thread/INFO] [STDOUT]: [fr.minewarfare.SQLDatabase:getValue:26]: Successfully connected to database
[22:18:24] [Server thread/INFO] [STDOUT]: [fr.minewarfare.SQLDatabase:getValue:42]: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Cobra45'/200, l='world', x=259,30, y=76,00, z=-114,15]'' at line 1

    public static void getValue(String table, String sectionRecover, String stringRecover, String recoverSection) {
        String returnString = null;
        try {
            Connection con = DriverManager.getConnection(urlbase + host + "/" + database, user, pass);
            System.out.println("Successfully connected to database");

            Statement q = con.createStatement();
            String sql = "SELECT * FROM " + table + " WHERE " + recoverSection + " = '" + stringRecover + "'";
            ResultSet rs = q.executeQuery(sql);

            while (rs.next()) {
                returnString = rs.getString(sectionRecover);
            }

            q.close();
            con.close();

            Main.network.sendToServer(new PacketSQLGetResult(returnString));

        } catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }

[robin4002]

C’est comme ça la bonne syntaxe pour appeler une fonction d’une variable cast :
((EntityPlayer)sender).getDisplayName()

Ou alors :

EntityPlayer player = (EntityPlayer)sender;
player.getDisplayName()

[Cobra45]

Toujours une erreur avec les deux. Elle semble juste un peu différente sur la fin

[23:03:13] [Server thread/INFO] [STDOUT]: [fr.minewarfare.SQLDatabase:getValue:42]: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Cobra45', siblings=[], style=Style{hasParent=true, color=null, bold=null, itali' at line 1

    @Override
    public void execute(MinecraftServer server, ICommandSender sender, String[] args) throws CommandException {
        if(sender instanceof EntityPlayer) {
            SQLDatabase.getValue("users", "grade", "" + ((EntityPlayer)sender).getDisplayName(), "pseudo");
        }
    }

    @Override
    public void execute(MinecraftServer server, ICommandSender sender, String[] args) throws CommandException {
        if(sender instanceof EntityPlayer) {
            EntityPlayer player = (EntityPlayer)sender;
            SQLDatabase.getValue("users", "grade", "" + player.getDisplayName(), "pseudo");
        }
    }

[robin4002]

getDisplayName ne renvois pas un string mais un ITextComponent.
Il faut utiliser player.getGameProfile().getName() pour avoir le nom du joueur en string (et il serait mieux de gérer les données utilisateurs en fonction du UUID, sinon en cas de changement de pseudo tu vas avoir des problèmes).

[Cobra45]

Tout fonctionne, merci.