Sorted out mime initialization.

Every mime related function in main __init__.py has a flag check for the
check if initialization has already done. This is nonsense, since it
should be done implicitly early on the converter is starting.

This commit straight the things out, and initialization is done in cli
module.

Also, function guess_type was removed, since it's just a proxy for
mimetypes.guess_type function.

ebook_converter/ebooks/metadata/__init__.py

@@ -2,22 +2,18 @@
 Provides abstraction for metadata reading.writing from a variety of ebook
 formats.
 """
+import mimetypes
 import os
 import re
 import sys
 import urllib.parse
 
-from ebook_converter import relpath, guess_type, prints, force_unicode
+from ebook_converter import relpath, prints, force_unicode
 from ebook_converter.utils.config_base import tweaks
 from ebook_converter.polyglot.builtins import as_unicode
 from ebook_converter.polyglot.urllib import unquote
 
 
-__license__ = 'GPL v3'
-__copyright__ = '2008, Kovid Goyal kovid@kovidgoyal.net'
-__docformat__ = 'restructuredtext en'
-
-
 try:
     _author_pat = re.compile(tweaks['authors_split_regex'])
 except Exception:
@@ -231,7 +227,7 @@ class Resource(object):
         self.path = None
         self.fragment = ''
         try:
-            self.mime_type = guess_type(href_or_path)[0]
+            self.mime_type = mimetypes.guess_type(href_or_path)[0]
         except:
             self.mime_type = None
         if self.mime_type is None:

ebook_converter/ebooks/metadata/fb2.py

@@ -1,6 +1,7 @@
 """
 Read meta information from fb2 files
 """
+import mimetypes
 import functools
 import os
 import random
@@ -225,7 +226,7 @@ def _parse_cover_data(root, imgid, mi, ctx):
         mime_extensions = guess_all_extensions(mimetype)
 
         if not mime_extensions and mimetype.startswith('image/'):
-            mimetype_fromid = guess_type(imgid)[0]
+            mimetype_fromid = mimetypes.guess_type(imgid)[0]
             if mimetype_fromid and mimetype_fromid.startswith('image/'):
                 mime_extensions = guess_all_extensions(mimetype_fromid)
 

ebook_converter/ebooks/metadata/opf2.py

@@ -6,6 +6,7 @@ import functools
 import glob
 import io
 import json
+import mimetypes
 import os
 import re
 import sys
@@ -74,7 +75,7 @@ class Resource(object):  # {{{
         self.path = None
         self.fragment = ''
         try:
-            self.mime_type = guess_type(href_or_path)[0]
+            self.mime_type = mimetypes.guess_type(href_or_path)[0]
         except Exception:
             self.mime_type = None
         if self.mime_type is None:
@@ -1304,8 +1305,8 @@ class OPF(object):  # {{{
                       'other.ms-coverimage'):
                 for item in self.guide:
                     if item.type.lower() == t:
-                        self.create_manifest_item(item.href(),
-                                                  guess_type(path)[0])
+                        self.create_manifest_item(
+                            item.href(), mimetypes.guess_type(path)[0])
 
     def get_metadata_element(self, name):
         matches = self.metadata_elem_path(self.metadata, name=name)