ADDED: ApiClient

ADDED: UsageDescription annotation
ADDED: Start class as entry point

first implementation of annotated resource descriptions

src/Start.java

@@ -1,4 +1,5 @@
 
+import api.ApiClient;
 import api.ApiService;
 import repository.DataException;
 import repository.RepositoryFactory;
@@ -16,5 +17,8 @@ public class Start {
         
         ApiService apiService = new ApiService();
         apiService.start();
+        
+        ApiClient client = new ApiClient(apiService);
+        String test = client.executeCommand("help GET blocks/height");
     }
 }

src/api/ApiClient.java

@@ -0,0 +1,123 @@
+package api;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import javax.ws.rs.Path;
+import javax.ws.rs.GET;
+import javax.ws.rs.POST;
+import javax.ws.rs.PUT;
+import javax.ws.rs.PATCH;
+import javax.ws.rs.DELETE;
+import javax.ws.rs.HttpMethod;
+
+public class ApiClient {
+    private class HelpString
+    {
+        public final Pattern pattern;
+        public final String fullPath;
+        public final String description;
+        
+        public HelpString(Pattern pattern, String fullPath, String description)
+        {
+            this.pattern = pattern;
+            this.fullPath = fullPath;
+            this.description = description;
+        }
+    }
+    
+    private static final Pattern HELP_COMMAND_PATTERN = Pattern.compile("^ *help *(?<command>.*)$", Pattern.CASE_INSENSITIVE);
+    private static final List<Class<? extends Annotation>> REST_METHOD_ANNOTATIONS = Arrays.asList(
+        GET.class,
+        POST.class,
+        PUT.class,
+        PATCH.class,
+        DELETE.class
+    );
+    
+    ApiService apiService;
+    List<HelpString> helpStrings;
+    
+    public ApiClient(ApiService apiService)
+    {
+        this.apiService = apiService;        
+        this.helpStrings = getHelpStrings(apiService.getResources());
+    }
+
+    private List<HelpString> getHelpStrings(Iterable<Class<?>> resources)
+    {
+        List<HelpString> result = new ArrayList<>();
+        
+        for (Class<?> resource : resources) {
+            Path resourcePath = resource.getDeclaredAnnotation(Path.class);
+            if(resourcePath == null)
+                continue;
+            
+            String resourcePathString = resourcePath.value();
+            
+            for(Method method : resource.getDeclaredMethods())
+            {
+                UsageDescription usageDescription = method.getAnnotation(UsageDescription.class);
+                if(usageDescription == null)
+                    continue;
+                
+                String usageDescriptionString = usageDescription.value();
+                
+                Path methodPath = method.getDeclaredAnnotation(Path.class);
+                String methodPathString = (methodPath != null) ? methodPath.value() : "";
+
+                for(Class<? extends Annotation> restMethodAnnotation : REST_METHOD_ANNOTATIONS)
+                {
+                    Annotation annotation = method.getDeclaredAnnotation(restMethodAnnotation);
+                    if(annotation == null)
+                        continue;
+
+                    HttpMethod httpMethod = annotation.annotationType().getDeclaredAnnotation(HttpMethod.class);
+                    String httpMethodString = httpMethod.value();
+
+                    Pattern pattern = Pattern.compile("^ *" + httpMethodString + " *" + getRegexPatternForPath(resourcePathString + methodPathString));
+                    String fullPath = httpMethodString + " " + resourcePathString + methodPathString;
+                    result.add(new HelpString(pattern, fullPath, usageDescriptionString));
+                }
+            }
+        }
+        
+        return result;
+    }
+    
+    private String getRegexPatternForPath(String path)
+    {
+        return path
+            .replaceAll("\\.", "\\.")       // escapes "." as "\."
+            .replaceAll("\\{.*?\\}", ".*?");  // replace placeholders "{...}" by the "ungreedy match anything" pattern ".*?"
+    }
+    
+    public String executeCommand(String command)
+    {
+        final Matcher helpMatch = HELP_COMMAND_PATTERN.matcher(command);
+        if(helpMatch.matches())
+        {
+            command = helpMatch.group("command");
+            StringBuilder help = new StringBuilder();
+            
+            for(HelpString helpString : helpStrings)
+            {
+                if(helpString.pattern.matcher(command).matches())
+                {
+                    help.append(helpString.fullPath + "\n");
+                    help.append(helpString.description + "\n");
+                }
+            }
+            
+            return help.toString();
+        }
+        
+        return null;
+    }
+}

src/api/ApiService.java

@@ -17,13 +17,14 @@ import settings.Settings;
 
 public class ApiService {
     private Server server;
+    private Set<Class<?>> resources;
 
     public ApiService()
     {
         // resources to register
-        Set<Class<?>> s = new HashSet<Class<?>>();
-        s.add(BlocksResource.class);
-        ResourceConfig config = new ResourceConfig(s);     
+        resources = new HashSet<Class<?>>();
+        resources.add(BlocksResource.class);
+        ResourceConfig config = new ResourceConfig(resources);     
 
         // create RPC server
         this.server = new Server(Settings.getInstance().getRpcPort());
@@ -44,14 +45,11 @@ public class ApiService {
         ServletHolder apiServlet = new ServletHolder(container);
         apiServlet.setInitOrder(1);
         context.addServlet(apiServlet, "/api/*");
-
-        /*
-        // Setup Swagger servlet
-        ServletHolder swaggerServlet = context.addServlet(DefaultJaxrsConfig.class, "/swagger-core");
-        swaggerServlet.setInitOrder(2);
-        swaggerServlet.setInitParameter("api.version", "1.0.0");
-        */
-
+    }
+    
+    Iterable<Class<?>> getResources()
+    {
+        return resources;
     }
 
     public void start()

src/api/BlocksResource.java

@@ -21,6 +21,7 @@ public class BlocksResource {
 
     @GET
     @Path("/height")
+    @UsageDescription("Returns the height of the blockchain")
     public static String getHeight() 
     {
         try (final Repository repository = RepositoryManager.getRepository()) {

src/api/UsageDescription.java

@@ -0,0 +1,14 @@
+package api;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(value={ElementType.TYPE,ElementType.METHOD})
+@Retention(value=RetentionPolicy.RUNTIME)
+@Documented
+public abstract @interface UsageDescription {
+    public abstract String value();
+}