[processing] use csv module for table writer

Author: alexbruy

python/plugins/processing/core/TableWriter.py

@@ -23,29 +23,53 @@
 # This will get replaced with a git SHA1 when you do a git archive
 __revision__ = '$Format:%H$'
 
-from qgis.core import *
-
-from PyQt4.QtCore import *
+import csv
+import codecs
+import cStringIO
 
 class TableWriter:
-
     def __init__(self, fileName, encoding, fields):
         self.fileName = fileName
-        self.writer = None
+        if not self.fileName.lower().endswith("csv"):
+            self.fileName += ".csv"
 
-        if encoding is None:
-            settings = QSettings()
-            encoding = settings.value("/ProcessingQGIS/encoding", "System")
+        self.encoding = encoding
+        if self.encoding is None or encoding == "System":
+            self.encoding = "utf-8"
 
-        if not fileName.endswith("csv"):
-            fileName += ".csv"
-        file = open(fileName, "w")
-        file.write(";".join(unicode(field.name()) for field in fields))
-        file.write("\n")
-        file.close()
+        with open(self.fileName, "wb") as csvFile:
+            self.writer = UnicodeWriter(csvFile, encoding=self.encoding)
+            self.writer.writerow(fields)
 
     def addRecord(self, values):
-        file = open(self.fileName, "a")
-        file.write(";".join([unicode(value) for value in values]))
-        file.write("\n")
-        file.close()
+        with open(self.fileName, "ab") as csvFile:
+            self.writer = UnicodeWriter(csvFile, encoding=self.encoding)
+            self.writer.writerow(values)
+
+    def addRecords(self, records):
+        with open(self.fileName, "ab") as csvFile:
+            self.writer = UnicodeWriter(csvFile, encoding=self.encoding)
+            self.writer.writerows(records)
+
+class UnicodeWriter:
+    def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
+        self.queue = cStringIO.StringIO()
+        self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
+        self.stream = f
+        self.encoder = codecs.getincrementalencoder(encoding)()
+
+    def writerow(self, row):
+        row = map(unicode, row)
+        try:
+            self.writer.writerow([s.encode("utf-8") for s in row])
+        except:
+            self.writer.writerow(row)
+        data = self.queue.getvalue()
+        data = data.decode("utf-8")
+        data = self.encoder.encode(data)
+        self.stream.write(data)
+        self.queue.truncate(0)
+
+    def writerows(self, rows):
+        for row in rows:
+            self.writerow(row)