Merge lp:~kissiel/checkbox/touch-logging into lp:checkbox

[Maciej Kisielewski]

This MR brings new logging to Checkbox-Touch. This makes logging more robust and easier to manage.

536d2ef checkbox-touch: add python logger
PythonLogger component is defined that uses pyotherside to forward logging events to python logging module.

fb7207c checkbox-touch: export checkbox.touch.qml logger to qml

9ce6636 checkbox-touch: use PythonLogger in checkbox-touch
Second, PythonLogger is used in Checkbox-Touch, overriding console.log and console.error, making them send events to python logging.

[Zygmunt Krynicki (zyga)]

This looks good, +1, some typos below

review: Needs Fixing

[lp:~kissiel/checkbox/touch-logging]

3569. By Maciej Kisielewski on 2015-02-09

checkbox-touch: add python logger

This patch introduces PythonLogger component that handles logging by sending it
through pyotherside to python, which in turn uses logging module to properly
record events. When this logger is created it overrides default behaviour of
console.log and console.error with python counterparts.

Signed-off-by: Maciej Kisielewski <email address hidden>

3570. By Maciej Kisielewski on 2015-02-09

checkbox-touch: export checkbox.touch.qml logger to qml

This patch makes checkbox.touch.qml logger available to QML as object compliant
to PythonObjectHandle component.

Signed-off-by: Maciej Kisielewski <email address hidden>

3571. By Maciej Kisielewski on 2015-02-09

checkbox-touch: use PythonLogger in checkbox-touch

This patch adds PythonLogger object to checkbox-touch. As console.log are now
pushed as logging.DEBUG and the logging level used is INFO, many messages
previously seen when using checkbox-touch are now silenced.

Signed-off-by: Maciej Kisielewski <email address hidden>

[Maciej Kisielewski (kissiel)]

> This looks good, +1, some typos below

Typos fixed. Repushed.

[Zygmunt Krynicki (zyga)]

+1

review: Approve

=== added file 'checkbox-touch/components/PythonLogger.qml'
--- checkbox-touch/components/PythonLogger.qml	1970-01-01 00:00:00 +0000
+++ checkbox-touch/components/PythonLogger.qml	2015-02-09 14:20:04 +0000
@@ -0,0 +1,98 @@
+/*
+ * This file is part of Checkbox
+ *
+ * Copyright 2015 Canonical Ltd.
+ *
+ * Authors:
+ * - Maciej Kisielewski <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*! \brief Python-driven logger
+    \inherits PythonObjectHandle
+
+    This component uses pyotherside to forward logging events to python.
+    It monkey-patches console.log and console.error to capture their calls
+    and forward those calls to python logger.
+*/
+import QtQuick 2.0
+
+PythonObjectHandle {
+
+    function debug(msg) {
+        invoke('debug', [msg], function() {});
+    }
+
+    function info(msg) {
+       invoke('info', [msg], function() {});
+    }
+
+    function warning(msg) {
+        invoke('warning', [msg], function() {});
+    }
+
+    function error(msg) {
+        invoke('error', [msg + "\nStacktrace:\n" + getStackTrace()], function() {});
+    }
+
+    function critical(msg) {
+        invoke('critical', [msg + "\nStacktrace:\n" + getStackTrace()], function() {});
+    }
+    /** get string containing pretty-formatted stack trace */
+    function getStackTrace() {
+        var stackTrace = "";
+        var callers = ((new Error).stack).split("\n");
+        callers.shift(); // remove current frame from ST (getStackTrace)
+        callers.shift(); // remove logging method frame from ST
+        for (var lvl in callers) {
+            stackTrace += "#" + lvl + " " + callers[lvl] + "\n";
+        }
+        return stackTrace;
+    }
+
+    /** Overridden invoke that doesn't log invoke calls */
+    function invoke(func, args, callback) {
+        if (py !== null && handle > 0) {
+            py.call("py_invoke", [handle, func, args], function(response) {
+                callback(response);
+            });
+        } else {
+            _original_console_error("unable to py_invoke: " + handle + ", " + func + ", " + JSON.stringify(args));
+            throw "py_invoke called without ready py and handle";
+        }
+    }
+
+    Component.onCompleted: {
+        /* save original logging facilities */
+        _original_console_log = console.log;
+        _original_console_error = console.error;
+    }
+
+    onHandleReady: {
+        /* monkey-patch console.log and console.error */
+        console.log = function() { debug(_argsToString(arguments)); };
+        console.error = function() { error(_argsToString(arguments)); };
+        debug("Python logger ready");
+    }
+
+    /** get string containing unpacked values from arguments object separated by spaces*/
+    function _argsToString(argsObj) {
+        var args = [];
+        for(var i = 0; i < argsObj.length; i++) args.push(argsObj[i]);
+        return args.join(" ");
+    }
+
+    property var _original_console_log
+    property var _original_console_error
+}
 
=== modified file 'checkbox-touch/main.qml'
--- checkbox-touch/main.qml	2015-01-29 14:58:11 +0000
+++ checkbox-touch/main.qml	2015-02-09 14:20:04 +0000
@@ -122,6 +122,20 @@
         }
     }
 
+    PythonLogger {
+        id: logger
+        py: py
+        Component.onCompleted: {
+            py.Component.onCompleted.connect(function() {
+                py.importModule("checkbox_touch", function() {
+                    py.call("checkbox_touch.get_qml_logger", [], function(handle) {
+                        logger.handle = handle;
+                    });
+                });
+            });
+        }
+    }
+
     PageStack {
         id: pageStack
         Component.onCompleted: push(welcomePage)
 
=== modified file 'checkbox-touch/py/checkbox_touch.py'
--- checkbox-touch/py/checkbox_touch.py	2015-02-06 15:51:40 +0000
+++ checkbox-touch/py/checkbox_touch.py	2015-02-09 14:20:04 +0000
@@ -799,5 +799,9 @@
     return manager
 
 
+def get_qml_logger():
+    return _manager.ref(logging.getLogger('checkbox.touch.qml'))
+
+
 create_app_object = CheckboxTouchApplication.create_and_get_handle
 _manager = bootstrap()