display logged error messages within program

src/gui_qt/lib/logger.py

@@ -0,0 +1,114 @@
+import sys
+from pathlib import Path
+
+from .codeeditor import _make_textformats
+from ..Qt import QtWidgets, QtCore, QtGui
+from nmreval.configs import config_paths
+
+
+STYLES = {'INFO': _make_textformats('black'),
+          'WARNING': _make_textformats('blue'),
+          'ERROR': _make_textformats('red', 'bold'),
+          'DEBUG': _make_textformats('black', 'italic'),
+          'file': _make_textformats('red', 'italic'),
+          'PyError': _make_textformats('red', 'bold-italic')}
+
+
+class LogHighlighter(QtGui.QSyntaxHighlighter):
+    msg = ['INFO', 'DEBUG', 'ERROR', 'WARNING']
+
+    def __init__(self, parent):
+        super(LogHighlighter, self).__init__(parent)
+
+        rules = list()
+        rules += [(r'\b\d{2}/\d{2}/\d{4} \d{2}:\d{2}:\d{2} - %s - .*' % m, 0, STYLES[m]) for m in LogHighlighter.msg]
+        rules += [(r'\b[A-Z]\w*Error: .*\b', 0, STYLES['PyError'])]
+        rules += [(r'\bFile .*', 0, STYLES['file'])]
+
+        self.rules = [(QtCore.QRegExp(pat), index, fmt) for (pat, index, fmt) in rules]
+
+    def highlightBlock(self, text):
+        """Apply syntax highlighting to the given block of text.
+        """
+        # Do other syntax formatting
+        for expression, nth, format in self.rules:
+            index = expression.indexIn(text, 0)
+
+            while index >= 0:
+                # We actually want the index of the nth match
+                index = expression.pos(nth)
+                try:
+                    length = expression.cap(nth).length()
+                except AttributeError:
+                    length = len(expression.cap(nth))
+                self.setFormat(index, length, format)
+                index = expression.indexIn(text, index + length)
+
+        self.setCurrentBlockState(0)
+
+    def match_multiline(self, text, delimiter, in_state, style):
+        if self.previousBlockState() == in_state:
+            start = 0
+            add = 0
+        else:
+            start = delimiter.indexIn(text)
+            add = delimiter.matchedLength()
+
+        while start >= 0:
+            end = delimiter.indexIn(text, start + add)
+            if end >= add:
+                length = end - start + add + delimiter.matchedLength()
+                self.setCurrentBlockState(0)
+            else:
+                self.setCurrentBlockState(in_state)
+                try:
+                    length = text.length() - start + add
+                except AttributeError:
+                    length = len(text) - start + add
+            # Apply formatting
+            self.setFormat(start, length, style)
+            # Look for the next match
+            start = delimiter.indexIn(text, start + length)
+
+        # Return True if still inside a multi-line string, False otherwise
+        if self.currentBlockState() == in_state:
+            return True
+        else:
+            return False
+
+
+class QLog(QtWidgets.QDialog):
+    def __init__(self, parent=None):
+        super(QLog, self).__init__(parent=parent)
+
+        self._initUi()
+
+        self.logfile = config_paths() / 'errors.log'
+
+        self.read_log()
+
+    def _initUi(self):
+
+        self.resize(960, 640)
+        layout = QtWidgets.QVBoxLayout()
+        self.plainTextEdit = QtWidgets.QPlainTextEdit()
+        self.plainTextEdit.highlight = LogHighlighter(self.plainTextEdit.document())
+        self.plainTextEdit.setReadOnly(True)
+        self.plainTextEdit.setMaximumBlockCount(50)
+        layout.addWidget(self.plainTextEdit)
+
+        self.buttonBox = QtWidgets.QDialogButtonBox()
+        self.buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Close)
+        self.buttonBox.accepted.connect(self.accept)
+        self.buttonBox.rejected.connect(self.reject)
+
+        layout.addWidget(self.buttonBox)
+
+        self.setLayout(layout)
+
+    def read_log(self):
+        with Path(self.logfile).open('r') as f:
+            text = f.readlines()
+
+        for lines in text[-100:]:
+            self.plainTextEdit.appendPlainText(lines[:-1])