add trace support (#38)

* add basic support for sending console logs to OutputWindow

* add trace config setting

* standardise logs

package.json

@@ -93,6 +93,11 @@
                                 "type": "string",
                                 "description": "Target Device ID (as indicated by 'adb devices'). Use this to specify which device is used for deployment when multiple devices are connected.",
                                 "default": ""
+                            },
+                            "trace": {
+                                "type": "boolean",
+                                "description": "Set to true to output debugging logs for diagnostics",
+                                "default": "false"
                             }
                         }
                     }

src/debugMain.js

@@ -17,7 +17,7 @@ const { ADBClient } = require('./adbclient');
 const { Debugger } = require('./debugger');
 const $ = require('./jq-promise');
 const { AndroidThread } = require('./threads');
-const { D, isEmptyObject } = require('./util');
+const { D, onMessagePrint, isEmptyObject } = require('./util');
 const { AndroidVariables } = require('./variables');
 const { evaluate } = require('./expressions');
 const ws_proxy = require('./wsproxy').proxy.Server(6037, 5037);
@@ -73,6 +73,9 @@ class AndroidDebugSession extends DebugSession {
         // flag to distinguish unexpected disconnection events (initiated from the device) vs user-terminated requests
         this._isDisconnecting = false;
 
+        // trace flag for printing diagnostic messages to the client Output Window
+        this.trace = false;
+
 		// this debugger uses one-based lines and columns
 		this.setDebuggerLinesStartAt1(true);
 		this.setDebuggerColumnsStartAt1(true);
@@ -106,14 +109,19 @@ class AndroidDebugSession extends DebugSession {
 	}
 
     LOG(msg) {
-        D(msg);
+        if (!this.trace) {
+            D(msg);
+        }
         // VSCode no longer auto-newlines output
         this.sendEvent(new OutputEvent(msg + os.EOL));
     }
 
     WARN(msg) {
         D(msg = 'Warning: '+msg);
-        this.sendEvent(new OutputEvent(msg + os.EOL));
+        // the message will already be sent if trace is enabled
+        if (!this.trace) {
+            this.sendEvent(new OutputEvent(msg + os.EOL));
+        }
     }
 
     failRequest(msg, response) {
@@ -223,6 +231,10 @@ class AndroidDebugSession extends DebugSession {
     }
 
 	launchRequest(response/*: DebugProtocol.LaunchResponse*/, args/*: LaunchRequestArguments*/) {
+        if (args && args.trace) {
+            this.trace = args.trace;
+            onMessagePrint(this.LOG.bind(this));
+        }
 
         try { D('Launching: ' + JSON.stringify(args)); } catch(ex) {}
         // app_src_root must end in a path-separator for correct validation of sub-paths
@@ -360,6 +372,9 @@ class AndroidDebugSession extends DebugSession {
                 this.sendResponse(response);
                 return this.dbgr.resume();
             })
+            .then(() => {
+                this.LOG('Application started');
+            })
             .fail(e => {
                 // exceptions use message, adbclient uses msg
                 this.LOG('Launch failed: '+(e.message||e.msg||'No additional information is available'));

src/jdwp.js

@@ -1,5 +1,5 @@
 const $ = require('./jq-promise');
-const { atob,btoa,D,getutf8bytes,fromutf8bytes,intToHex } = require('./util');
+const { btoa,D,E,getutf8bytes,fromutf8bytes,intToHex } = require('./util');
 /*
     JDWP - The Java Debug Wire Protocol
 */
@@ -96,8 +96,8 @@ function _JDWP() {
             return;
 		}
 		
-		if (this.errorcode != 0) {
-		    console.error("Command failed: error " + this.errorcode, this);
+		if (this.errorcode !== 0) {
+		    E(`JDWP command failed '${this.command.name}'. Error ${this.errorcode}`, this);
         }
 		
 		if (!this.errorcode && this.command && this.command.replydecodefn) {

src/jq-promise.js

@@ -40,7 +40,7 @@ var Deferred = exports.Deferred = function(p, parent) {
             var faildef = $.Deferred(null, this);
             var p = this._promise.catch(function(a) {
                 if (a.stack) {
-                    console.error(a.stack);
+                    util.E(a.stack);
                     a = [a];
                 }
                 if (this.def._context === null && this.def._parent)

src/util.js

@@ -1,13 +1,18 @@
 const crypto = require('crypto');
 
 var nofn = function () { };
-var D = exports.D = console.log.bind(console);
-var E = exports.E = console.error.bind(console);
-var W = exports.W = console.warn.bind(console);
+const messagePrintCallbacks = new Set();
+var D = exports.D = (...args) => (console.log(...args), messagePrintCallbacks.forEach(cb => cb(...args)))
+var E = exports.E = (...args) => (console.error(...args), messagePrintCallbacks.forEach(cb => cb(...args)))
+var W = exports.W = (...args) => (console.warn(...args), messagePrintCallbacks.forEach(cb => cb(...args)))
 var DD = nofn, cl = D, printf = D;
 var print_jdwp_data = nofn;// _print_jdwp_data;
 var print_packet = nofn;//_print_packet;
 
+exports.onMessagePrint = function(cb) {
+    messagePrintCallbacks.add(cb);
+}
+
 Array.first = function (arr, fn, defaultvalue) {
 	var idx = Array.indexOfFirst(arr, fn);
 	return idx < 0 ? defaultvalue : arr[idx];