accessor: Add mode and kwargs parameters and default to binary mode

Fix issue #19 based on the description and progress from PR xenserver#24.
Allows for opening text and binary files in text and binary modes.

Mode, encoding and error handling can be set by passing the parameters
"encoding" and "errors" using the kwargs parameters from openAddress()
and writeFile() to open(mode, **kwargs) and ftp.makefile(mode, **kwargs).

Signed-off-by: Bernhard Kaindl <bernhard.kaindl@cloud.com>

Author: bernhardkaindl

xcp/accessor.py

@@ -71,7 +71,7 @@ def access(self, name):
 
         return True
 
-    def openAddress(self, address):
+    def openAddress(self, address, mode="", **kwargs):
         """should be overloaded"""
         pass
 
@@ -99,9 +99,9 @@ def __init__(self, location, ro):
         super(FilesystemAccessor, self).__init__(ro)
         self.location = location
 
-    def openAddress(self, address):
+    def openAddress(self, address, mode="rb", **kwargs):
         try:
-            filehandle = open(os.path.join(self.location, address), 'r')
+            filehandle = open(os.path.join(self.location, address), mode, **kwargs)
         except OSError as e:
             if e.errno == errno.EIO:
                 self.lastError = 5
@@ -165,9 +165,9 @@ def finish(self):
             os.rmdir(self.location)
             self.location = None
 
-    def writeFile(self, in_fh, out_name):
+    def writeFile(self, in_fh, out_name, mode="wb", **kwargs):
         logger.info("Copying to %s" % os.path.join(self.location, out_name))
-        out_fh = open(os.path.join(self.location, out_name), 'w')
+        out_fh = open(os.path.join(self.location, out_name), mode, **kwargs)
         return self._writeFile(in_fh, out_fh)
 
     def __del__(self):
@@ -220,9 +220,9 @@ def __init__(self, baseAddress, ro):
         super(FileAccessor, self).__init__(ro)
         self.baseAddress = baseAddress
 
-    def openAddress(self, address):
+    def openAddress(self, address, mode="rb", **kwargs):
         try:
-            file = open(os.path.join(self.baseAddress, address))
+            file = open(os.path.join(self.baseAddress, address), mode, **kwargs)
         except IOError as e:
             if e.errno == errno.EIO:
                 self.lastError = 5
@@ -240,9 +240,9 @@ def openAddress(self, address):
             return False
         return file
 
-    def writeFile(self, in_fh, out_name):
+    def writeFile(self, in_fh, out_name, mode="wb", **kwargs):
         logger.info("Copying to %s" % os.path.join(self.baseAddress, out_name))
-        out_fh = open(os.path.join(self.baseAddress, out_name), 'w')
+        out_fh = open(os.path.join(self.baseAddress, out_name), mode, **kwargs)
         return self._writeFile(in_fh, out_fh)
 
     def __repr__(self):
@@ -331,13 +331,13 @@ def access(self, path):
             self.lastError = 500
             return False
 
-    def openAddress(self, address):
+    def openAddress(self, address, mode="rb", **kwargs):
         logger.debug("Opening "+address)
         self._cleanup()
         url = urllib.parse.unquote(address)
 
         self.ftp.voidcmd('TYPE I')
-        s = self.ftp.transfercmd('RETR ' + url).makefile('rb')
+        s = self.ftp.transfercmd('RETR ' + url).makefile(mode, **kwargs)
         self.cleanup = True
         return s