Add some basic tracking for HTTP requests and websockets

This should allow for easier identification of misbehaving computers,
which are consuming a large amount of bandwidth.

src/main/java/dan200/computercraft/core/apis/http/HTTPRequest.java

@@ -15,6 +15,7 @@ import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.apis.IAPIEnvironment;
 import dan200.computercraft.core.apis.handles.BinaryInputHandle;
 import dan200.computercraft.core.apis.handles.EncodedInputHandle;
+import dan200.computercraft.core.tracking.TrackingField;
 
 import javax.annotation.Nonnull;
 import java.io.*;
@@ -134,6 +135,11 @@ public class HTTPRequest implements Runnable
                 }
             }
 
+            // Add request size and count to the tracker before opening the connection
+            m_environment.addTrackingChange( TrackingField.HTTP_REQUESTS );
+            m_environment.addTrackingChange( TrackingField.HTTP_UPLOAD,
+                getHeaderSize( connection.getRequestProperties() ) + (m_postText == null ? 0 : m_postText.length()) );
+
             // Send POST text
             if( m_postText != null )
             {
@@ -178,6 +184,9 @@ public class HTTPRequest implements Runnable
                 headers.put( header.getKey(), joiner.join( header.getValue() ) );
             }
 
+            m_environment.addTrackingChange( TrackingField.HTTP_DOWNLOAD,
+                getHeaderSize( connection.getHeaderFields() ) + result.length );
+
             InputStream contents = new ByteArrayInputStream( result );
             ILuaObject stream = wrapStream(
                 m_binary ? new BinaryInputHandle( contents ) : new EncodedInputHandle( contents, connection.getContentEncoding() ),
@@ -248,4 +257,15 @@ public class HTTPRequest implements Runnable
             }
         };
     }
+
+    private static long getHeaderSize( Map<String, List<String>> headers )
+    {
+        long size = 0;
+        for( Map.Entry<String, List<String>> header : headers.entrySet() )
+        {
+            size += header.getKey() == null ? 0 : header.getKey().length();
+            for( String value : header.getValue() ) size += value == null ? 0 : value.length() + 1;
+        }
+        return size;
+    }
 }

src/main/java/dan200/computercraft/core/apis/http/WebsocketConnection.java

@@ -12,6 +12,7 @@ import dan200.computercraft.api.lua.ILuaObject;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.apis.HTTPAPI;
 import dan200.computercraft.core.apis.IAPIEnvironment;
+import dan200.computercraft.core.tracking.TrackingField;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandlerContext;
@@ -115,14 +116,19 @@ public class WebsocketConnection extends SimpleChannelInboundHandler<Object> imp
         WebSocketFrame frame = (WebSocketFrame) msg;
         if( frame instanceof TextWebSocketFrame )
         {
-            computer.queueEvent( MESSAGE_EVENT, new Object[] { url, ((TextWebSocketFrame) frame).text() } );
+            String data = ((TextWebSocketFrame) frame).text();
+
+            computer.addTrackingChange( TrackingField.WEBSOCKET_INCOMING, data.length() );
+            computer.queueEvent( MESSAGE_EVENT, new Object[]{ url, data } );
         }
         else if( frame instanceof BinaryWebSocketFrame )
         {
             ByteBuf data = frame.content();
             byte[] converted = new byte[data.readableBytes()];
             data.readBytes( converted );
-            computer.queueEvent( MESSAGE_EVENT, new Object[] { url, data } );
+
+            computer.addTrackingChange( TrackingField.WEBSOCKET_INCOMING, converted.length );
+            computer.queueEvent( MESSAGE_EVENT, new Object[]{ url, converted } );
         }
         else if( frame instanceof CloseWebSocketFrame )
         {
@@ -168,6 +174,7 @@ public class WebsocketConnection extends SimpleChannelInboundHandler<Object> imp
             {
                 checkOpen();
                 String text = arguments.length > 0 && arguments[0] != null ? arguments[0].toString() : "";
+                computer.addTrackingChange( TrackingField.WEBSOCKET_OUTGOING, text.length() );
                 channel.writeAndFlush( new TextWebSocketFrame( text ) );
                 return null;
             }

src/main/java/dan200/computercraft/core/tracking/TrackingField.java

@@ -17,9 +17,16 @@ public class TrackingField
     public static final TrackingField SERVER_COUNT = TrackingField.of( "server_count", "Server task count", x -> String.format( "%4d", x ) );
     public static final TrackingField SERVER_TIME = TrackingField.of( "server_time", "Server task time", x -> String.format( "%7.1fms", x / 1e6 ) );
 
-    public static final TrackingField PERIPHERAL_OPS = TrackingField.of( "peripheral", "Peripheral calls", x -> String.format( "%6d", x ) );
+    public static final TrackingField PERIPHERAL_OPS = TrackingField.of( "peripheral", "Peripheral calls", TrackingField::formatDefault );
-    public static final TrackingField FS_OPS = TrackingField.of( "fs", "Filesystem operations", x -> String.format( "%6d", x ) );
+    public static final TrackingField FS_OPS = TrackingField.of( "fs", "Filesystem operations", TrackingField::formatDefault );
-    public static final TrackingField TURTLE_OPS = TrackingField.of( "turtle", "Turtle operations", x -> String.format( "%6d", x ) );
+    public static final TrackingField TURTLE_OPS = TrackingField.of( "turtle", "Turtle operations", TrackingField::formatDefault );
+
+    public static final TrackingField HTTP_REQUESTS = TrackingField.of( "http", "HTTP requests", TrackingField::formatDefault );
+    public static final TrackingField HTTP_UPLOAD = TrackingField.of( "http_upload", "HTTP upload", TrackingField::formatBytes );
+    public static final TrackingField HTTP_DOWNLOAD = TrackingField.of( "http_download", "HTTT download", TrackingField::formatBytes );
+
+    public static final TrackingField WEBSOCKET_INCOMING = TrackingField.of( "websocket_incoming", "Websocket incoming", TrackingField::formatBytes );
+    public static final TrackingField WEBSOCKET_OUTGOING = TrackingField.of( "websocket_outgoing", "Websocket outgoing", TrackingField::formatBytes );
 
     private final String id;
     private final String displayName;
@@ -58,4 +65,24 @@ public class TrackingField
     {
         return Collections.unmodifiableMap( fields );
     }
+
+    private static String formatDefault( long value )
+    {
+        return String.format( "%6d", value );
+    }
+
+    /**
+     * So technically a kibibyte, but let's not argue here.
+     */
+    private static final int KILOBYTE_SIZE = 1024;
+
+    private static final String SI_PREFIXES = "KMGT";
+
+    private static String formatBytes( long bytes )
+    {
+        if( bytes < 1024 ) return String.format( "%10d B", bytes );
+        int exp = (int) (Math.log( bytes ) / Math.log( KILOBYTE_SIZE ));
+        if( exp > SI_PREFIXES.length() ) exp = SI_PREFIXES.length();
+        return String.format( "%10.1f %siB", bytes / Math.pow( KILOBYTE_SIZE, exp ), SI_PREFIXES.charAt( exp - 1 ) );
+    }
 }