massive refactoring to switch from camelCase to snake_case:

historically, Libervia (SàT before) was using camelCase as allowed by PEP8 when using a
pre-PEP8 code, to use the same coding style as in Twisted.

However, snake_case is more readable and it's better to follow PEP8 best practices, so it
has been decided to move on full snake_case. Because Libervia has a huge codebase, this
ended with a ugly mix of camelCase and snake_case.

To fix that, this patch does a big refactoring by renaming every function and method
(including bridge) that are not coming from Twisted or Wokkel, to use fully snake_case.

This is a massive change, and may result in some bugs.

sat/plugins/plugin_xep_0264.py

@@ -81,15 +81,15 @@ class XEP_0264(object):
     def __init__(self, host):
         log.info(_("Plugin XEP_0264 initialization"))
         self.host = host
-        host.trigger.add("XEP-0234_buildFileElement", self._addFileThumbnails)
-        host.trigger.add("XEP-0234_parseFileElement", self._getFileThumbnails)
+        host.trigger.add("XEP-0234_buildFileElement", self._add_file_thumbnails)
+        host.trigger.add("XEP-0234_parseFileElement", self._get_file_thumbnails)
 
-    def getHandler(self, client):
+    def get_handler(self, client):
         return XEP_0264_handler()
 
     ## triggers ##
 
-    def _addFileThumbnails(self, client, file_elt, extra_args):
+    def _add_file_thumbnails(self, client, file_elt, extra_args):
         try:
             thumbnails = extra_args["extra"][C.KEY_THUMBNAILS]
         except KeyError:
@@ -103,7 +103,7 @@ class XEP_0264(object):
             thumbnail_elt["height"] = str(height)
         return True
 
-    def _getFileThumbnails(self, client, file_elt, file_data):
+    def _get_file_thumbnails(self, client, file_elt, file_data):
         thumbnails = []
         for thumbnail_elt in file_elt.elements(NS_THUMBS, "thumbnail"):
             uri = thumbnail_elt["uri"]
@@ -130,7 +130,7 @@ class XEP_0264(object):
 
     ## thumbnails generation ##
 
-    def getThumbId(self, image_uid, size):
+    def get_thumb_id(self, image_uid, size):
         """return an ID unique for image/size combination
 
         @param image_uid(unicode): unique id of the image
@@ -140,13 +140,13 @@ class XEP_0264(object):
         """
         return hashlib.sha256(repr((image_uid, size)).encode()).hexdigest()
 
-    def _blockingGenThumb(
+    def _blocking_gen_thumb(
             self, source_path, size=None, max_age=None, image_uid=None,
             fix_orientation=True):
         """Generate a thumbnail for image
 
         This is a blocking method and must be executed in a thread
-        params are the same as for [generateThumbnail]
+        params are the same as for [generate_thumbnail]
         """
         if size is None:
             size = self.SIZE_SMALL
@@ -159,9 +159,9 @@ class XEP_0264(object):
         if fix_orientation:
             img = ImageOps.exif_transpose(img)
 
-        uid = self.getThumbId(image_uid or source_path, size)
+        uid = self.get_thumb_id(image_uid or source_path, size)
 
-        with self.host.common_cache.cacheData(
+        with self.host.common_cache.cache_data(
             PLUGIN_INFO[C.PI_IMPORT_NAME], uid, MIME_TYPE, max_age
         ) as f:
             img.save(f, SAVE_FORMAT)
@@ -170,7 +170,7 @@ class XEP_0264(object):
 
         return img.size, uid
 
-    def generateThumbnail(
+    def generate_thumbnail(
         self, source_path, size=None, max_age=None, image_uid=None, fix_orientation=True):
         """Generate a thumbnail of image
 
@@ -178,7 +178,7 @@ class XEP_0264(object):
         @param size(int, None): max size of the thumbnail
             can be one of self.SIZE_*
             None to use default value (i.e. self.SIZE_SMALL)
-        @param max_age(int, None): same as for [memory.cache.Cache.cacheData])
+        @param max_age(int, None): same as for [memory.cache.Cache.cache_data])
         @param image_uid(unicode, None): unique ID to identify the image
             use hash whenever possible
             if None, source_path will be used
@@ -188,7 +188,7 @@ class XEP_0264(object):
             - unique Id of the thumbnail
         """
         d = threads.deferToThread(
-            self._blockingGenThumb, source_path, size, max_age, image_uid=image_uid,
+            self._blocking_gen_thumb, source_path, size, max_age, image_uid=image_uid,
             fix_orientation=fix_orientation
         )
         d.addErrback(