More work on standalone version, fix plugin

DeDRM_plugin/standalone/jsonconfig.py

@@ -0,0 +1,140 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# CLI interface for the DeDRM plugin (useable without Calibre, too)
+# Config implementation
+
+from __future__ import absolute_import, print_function
+
+# Taken from Calibre code - Copyright © 2008, Kovid Goyal kovid@kovidgoyal.net, GPLv3
+
+#@@CALIBRE_COMPAT_CODE@@
+
+import sys, os, codecs, json
+
+config_dir = "/"
+CONFIG_DIR_MODE = 0o700
+iswindows = sys.platform.startswith('win')
+
+
+filesystem_encoding = sys.getfilesystemencoding()
+if filesystem_encoding is None:
+    filesystem_encoding = 'utf-8'
+else:
+    try:
+        if codecs.lookup(filesystem_encoding).name == 'ascii':
+            filesystem_encoding = 'utf-8'
+            # On linux, unicode arguments to os file functions are coerced to an ascii
+            # bytestring if sys.getfilesystemencoding() == 'ascii', which is
+            # just plain dumb. This is fixed by the icu.py module which, when
+            # imported changes ascii to utf-8
+    except Exception:
+        filesystem_encoding = 'utf-8'
+
+
+class JSONConfig(dict):
+
+    EXTENSION = '.json'
+
+
+    def __init__(self, rel_path_to_cf_file, base_path=config_dir):
+        dict.__init__(self)
+        self.no_commit = False
+        self.defaults = {}
+        self.file_path = os.path.join(base_path,
+                *(rel_path_to_cf_file.split('/')))
+        self.file_path = os.path.abspath(self.file_path)
+        if not self.file_path.endswith(self.EXTENSION):
+            self.file_path += self.EXTENSION
+
+        self.refresh()
+
+    def mtime(self):
+        try:
+            return os.path.getmtime(self.file_path)
+        except OSError:
+            return 0
+
+    def touch(self):
+        try:
+            os.utime(self.file_path, None)
+        except OSError:
+            pass
+
+
+    def decouple(self, prefix):
+        self.file_path = os.path.join(os.path.dirname(self.file_path), prefix + os.path.basename(self.file_path))
+        self.refresh()
+
+    def refresh(self, clear_current=True):
+        d = {}
+        if os.path.exists(self.file_path):
+            with open(self.file_path, "rb") as f:
+                raw = f.read()
+                try:
+                    d = self.raw_to_object(raw) if raw.strip() else {}
+                except SystemError:
+                    pass
+                except:
+                    import traceback
+                    traceback.print_exc()
+                    d = {}
+        if clear_current:
+            self.clear()
+        self.update(d)
+
+    def has_key(self, key):
+        return dict.__contains__(self, key)
+
+    def set(self, key, val):
+        self.__setitem__(key, val)
+
+    def __delitem__(self, key):
+        try:
+            dict.__delitem__(self, key)
+        except KeyError:
+            pass  # ignore missing keys
+        else:
+            self.commit()
+
+    def commit(self):
+        if self.no_commit:
+            return
+        if hasattr(self, 'file_path') and self.file_path:
+            dpath = os.path.dirname(self.file_path)
+            if not os.path.exists(dpath):
+                os.makedirs(dpath, mode=CONFIG_DIR_MODE)
+            with open(self.file_path, "w") as f:
+                raw = self.to_raw()
+                f.seek(0)
+                f.truncate()
+                f.write(raw)
+
+    def __enter__(self):
+        self.no_commit = True
+
+    def __exit__(self, *args):
+        self.no_commit = False
+        self.commit()
+
+    def raw_to_object(self, raw):
+        return json.loads(raw)
+
+    def to_raw(self):
+        return json.dumps(self, ensure_ascii=False)
+
+    def __getitem__(self, key):
+        try:
+            return dict.__getitem__(self, key)
+        except KeyError:
+            return self.defaults[key]
+
+    def get(self, key, default=None):
+        try:
+            return dict.__getitem__(self, key)
+        except KeyError:
+            return self.defaults.get(key, default)
+
+    def __setitem__(self, key, val):
+        dict.__setitem__(self, key, val)
+        self.commit()