Print proper usage messages for commands.

Author: Aleksi Salmela

src/main/java/fi/helsinki/cs/tmc/cli/backend/TmcUtil.java

@@ -172,7 +172,6 @@ public static URI sendPaste(CliContext ctx, Exercise exercise, String message) {
         } catch (Exception e) {
             TmcUtil.handleTmcExceptions(ctx, e);
             logger.error("Failed to send paste", e);
-            ctx.getIo().println(e.toString());
             return null;
         }
     }
@@ -238,6 +237,7 @@ protected static void handleTmcExceptions(CliContext ctx, Exception exception) {
             return;
         }
         logger.error("Command failed in tmc-core", exception);
+        //TODO we seem to write twice error message; here and in the commands.
         io.errorln("Command failed in tmc-core, check tmc-cli.log file for more info");
     }
 

src/main/java/fi/helsinki/cs/tmc/cli/command/DownloadExercisesCommand.java

@@ -27,6 +27,11 @@ public class DownloadExercisesCommand extends AbstractCommand {
     private CliContext ctx;
     private boolean showAll;
 
+    @Override
+    public String[] getUsages() {
+        return new String[] {"[-a] COURSE"};
+    }
+
     @Override
     public void getOptions(Options options) {
         options.addOption("a", "all", false,
@@ -44,7 +49,7 @@ public void run(CliContext context, CommandLine args) {
         String[] stringArgs = args.getArgs();
         if (stringArgs.length == 0 || stringArgs.length > 1) {
             io.errorln("You must give a course name as an argument.");
-            io.errorln("Usage: tmc download COURSE");
+            printUsage(ctx);
             return;
         }
 

src/main/java/fi/helsinki/cs/tmc/cli/command/InfoCommand.java

@@ -31,6 +31,11 @@ public class InfoCommand extends AbstractCommand {
     private boolean fetchFromInternet;
     private boolean showAll;
 
+    @Override
+    public String[] getUsages() {
+        return new String[] {"[-a] [-i] COURSE-OR-EXERSICE"};
+    }
+
     @Override
     public void getOptions(Options options) {
         options.addOption("a", "all", false, "Show all information for a specific course");
@@ -55,6 +60,7 @@ public void run(CliContext context, CommandLine args) {
         if (fetchFromInternet) {
             if (useWorkingDirectory) {
                 io.errorln("You must give a course as an argument.");
+                printUsage(ctx);
                 return;
             }
             String courseName = stringArgs[0];
@@ -83,6 +89,7 @@ private void printLocalInfo(String[] stringArgs) {
             io.errorln("You have to be in a course directory"
                     + " or use the -i option with the course name "
                     + "to get the information from the server.");
+            printUsage(ctx);
             return;
         }
 
@@ -97,6 +104,7 @@ private void printLocalInfo(String[] stringArgs) {
         } else {
             if (stringArgs.length != 1) {
                 io.errorln("You can only give one path for this command.");
+                printUsage(ctx);
                 return;
             }
             String path = stringArgs[0];
@@ -120,6 +128,7 @@ private void printInfoFromParameters(String pathName) {
             io.errorln("Not a course directory. ");
             io.errorln("Use the -i option to get course from "
                     + "server.");
+            printUsage(ctx);
         }
     }
 

src/main/java/fi/helsinki/cs/tmc/cli/command/ListExercisesCommand.java

@@ -26,6 +26,11 @@ public class ListExercisesCommand extends AbstractCommand {
     private CliContext ctx;
     private Io io;
 
+    @Override
+    public String[] getUsages() {
+        return new String[] {"[-n] [-i] COURSE"};
+    }
+
     @Override
     public void getOptions(Options options) {
         options.addOption("n", "no-pager", false, "Don't use a pager to list the exercises");
@@ -141,6 +146,7 @@ private String getExercisesAsString(String courseName, List<Exercise> exercises)
         return sb.toString();
     }
 
+    //TODO duplicate code existed in info command!!!!!!!
     private String getDeadline(Exercise exercise) {
         String deadline = exercise.getDeadline();
         if (deadline == null) {

src/main/java/fi/helsinki/cs/tmc/cli/command/LoginCommand.java

@@ -23,6 +23,11 @@ public class LoginCommand extends AbstractCommand {
     private String username;
     private String password;
 
+    @Override
+    public String[] getUsages() {
+        return new String[] {"[-u=USERNAME] [-p=PASSWORD] [-s=SERVER_ADDRESS]"};
+    }
+
     @Override
     public void getOptions(Options options) {
         options.addOption("u", "user", true, "TMC username");
@@ -35,6 +40,12 @@ public void run(CliContext context, CommandLine args) {
         this.ctx = context;
         this.io = ctx.getIo();
 
+        if(args.getArgs().length > 0) {
+            io.errorln("Login doesn't take any arguments.");
+            printUsage(context);
+            return;
+        }
+
         if (!ctx.loadBackendWithoutLogin()) {
             return;
         }

src/main/java/fi/helsinki/cs/tmc/cli/command/LogoutCommand.java

@@ -4,6 +4,7 @@
 import fi.helsinki.cs.tmc.cli.core.AbstractCommand;
 import fi.helsinki.cs.tmc.cli.core.CliContext;
 import fi.helsinki.cs.tmc.cli.core.Command;
+import fi.helsinki.cs.tmc.cli.io.Io;
 
 import org.apache.commons.cli.CommandLine;
 import org.apache.commons.cli.Options;
@@ -17,7 +18,14 @@ public void getOptions(Options options) {
 
     @Override
     public void run(CliContext context, CommandLine args) {
+        Io io = context.getIo();
+        if(args.getArgs().length > 0) {
+            io.errorln("Logout doesn't take any arguments.");
+            printUsage(context);
+            return;
+        }
+
         SettingsIo.delete();
-        context.getIo().println("Logged out.");
+        io.println("Logged out.");
     }
 }

src/main/java/fi/helsinki/cs/tmc/cli/command/PasteCommand.java

@@ -64,7 +64,7 @@ public void run(CliContext context, CommandLine args) {
             return;
         }
 
-        String message;
+        String message = "";
         if (!args.hasOption("n")) {
             if (args.hasOption("m")) {
                 message = args.getOptionValue("m");
@@ -77,11 +77,7 @@ public void run(CliContext context, CommandLine args) {
                                 + "#   Lines beginning with # are comments and will be ignored.",
                         "tmc-paste-message",
                         true);
-            } else {
-                message = "";
             }
-        } else {
-            message = "";
         }
 
         String exerciseName = exercisenames.get(0);

src/main/java/fi/helsinki/cs/tmc/cli/command/PropertiesCommand.java

@@ -21,6 +21,11 @@ public class PropertiesCommand extends AbstractCommand {
             = LoggerFactory.getLogger(PropertiesCommand.class);
     private Io io;
 
+    @Override
+    public String[] getUsages() {
+        return new String[] {"KEY VALUE ..."};
+    }
+
     @Override
     public void getOptions(Options options) {
         options.addOption("u", "unset", false, "Unset given property keys");
@@ -40,7 +45,8 @@ public void run(CliContext context, CommandLine args) {
         }
 
         if (arguments.length % 2 == 1 && !unset) {
-            io.errorln("Invalid argument count. Usage: tmc prop KEY VALUE ...");
+            io.errorln("Invalid argument count.");
+            printUsage(ctx);
             return;
         }
 

src/main/java/fi/helsinki/cs/tmc/cli/command/UpdateCommand.java

@@ -37,6 +37,7 @@ public void run(CliContext context, CommandLine args) {
 
         if (stringArgs.length > 0) {
             io.errorln("Use in the course directory");
+            printUsage(ctx);
             return;
         }
 

src/main/java/fi/helsinki/cs/tmc/cli/core/AbstractCommand.java

@@ -12,7 +12,9 @@
 import org.slf4j.LoggerFactory;
 
 public abstract class AbstractCommand {
+
     private static final Logger logger = LoggerFactory.getLogger(AbstractCommand.class);
+    private Command command;
 
     /**
      * Override this method if you want longer description for the command than
@@ -24,6 +26,17 @@ public String getDescription() {
         return null;
     }
 
+    /**
+     * Override this method if you want to give usage description.
+     * Dont't add the 'tmc-cli COMMAND' prefix, because it is added
+     * automatically to every line.
+     *
+     * @return Description text
+     */
+    public String[] getUsages() {
+        return null;
+    }
+
     public abstract void getOptions(Options options);
 
     private Options getOptions() {
@@ -69,18 +82,59 @@ public CommandLine parseArgs(CliContext context, String[] stringArgs) {
         }
 
         if (args.hasOption("h")) {
+            printHelp(context);
+            return null;
+        }
+        return args;
+    }
+
+    protected void printUsage(CliContext context) {
+        Io io = context.getIo();
+        io.println(getUsageString());
+    }
+
+    private Command getCommand() {
+        if(this.command == null) {
             Class<Command> klass;
             klass = CommandFactory.castToCommandClass(this.getClass());
-            Command command = CommandFactory.getCommand(klass);
+            this.command = CommandFactory.getCommand(klass);
+        }
+        return this.command;
+    }
+
+    private void printHelp(CliContext context) {
+        Io io = context.getIo();
+        Options options = getOptions();
 
-            String usage = "tmc " + command.name();
-            String desc = getDescription();
-            if (desc == null) {
-                desc = command.desc();
+        String usage = getUsageString();
+        String desc = getDescription();
+        if (desc == null) {
+            desc = getCommand().desc();
+        }
+        HelpGenerator.run(io, usage, desc, options);
+    }
+
+    /**
+     * TODO print the "Usage:" and "Or:" prefixes to every line.
+     * @return The printable usage string.
+     */
+    private String getUsageString() {
+        String prefix = "tmc " + getCommand().name() + " ";
+        String[] usages = getUsages();
+        if(usages == null) {
+            return prefix;
+        }
+
+        StringBuilder builder = new StringBuilder();
+        boolean first = true;
+        for(String line : usages) {
+            if(!first) {
+                builder.append("\n");
             }
-            HelpGenerator.run(io, usage, desc, options);
-            return null;
+            builder.append(prefix);
+            builder.append(line);
+            first = false;
         }
-        return args;
+        return builder.toString();
     }
-}
+}