encode api: revert to methods instead of data members (format, description, ..),...

diff --git a/encode/api.py b/encode/api.py
index ef4bd2084831a5a2fa53d93ba40b8afa80ac279b..628b1ddd07dd1591ff489c5d4e945a23894bbfab 100644 (file)
--- a/encode/api.py
+++ b/encode/api.py
@@ -24,22 +24,13 @@ from timeside.core import Interface, TimeSideError
 class IEncoder(Interface):
     """Encoder driver interface"""
 
-    format = ""
-    """Encoding format as a short string Example: "MP3", "OGG", "AVI", ... """
-
-    description = ""
-    """String describing what this encoding format provides, is good
-       for, etc... The description is meant to help the end user decide what
-       format is good for him/her """
-
-    file_extension = ""
-    """Filename extension corresponding to this encoding format"""
-
-    mime_type = ""
-    """Mime type corresponding to this encoding format"""
+    # Remark: the method prototypes do not include any self or cls argument
+    # because an interface is meant to show what methods a class must expose
+    # from the caller's point of view. However, when implementing the class
+    # you'll obviously want to include this extra argument.
 
     # FIXME: this constructor conflicts with the core component architecture
-    def __init__(self, output, nchannels, samplerate):
+    def __init__(output, nchannels, samplerate):
         """The constructor must always accept the output, nchannels and samplerate 
         arguments.  It may accepts extra arguments such as bitrate, depth, etc.., 
         but these must be optionnal, that is have a default value.
@@ -49,23 +40,40 @@ class IEncoder(Interface):
         block of binary data.
         """
 
-    def set_metadata(self, metadata):
+    def format():
+        """Return the encode/encoding format as a short string
+        Example: "MP3", "OGG", "AVI", ...
+        """
+
+    def description():
+        """Return a string describing what this encode format provides, is good
+        for, etc... The description is meant to help the end user decide what
+        format is good for him/her
+        """
+
+    def file_extension():
+        """Return the filename extension corresponding to this encode format"""
+
+    def mime_type():
+        """Return the mime type corresponding to this encode format"""
+
+    def set_metadata(metadata):
         """metadata is a tuple containing tuples for each descriptor return by
         the dc.Ressource of the item, in the model order :
         ((name1, value1),(name2, value2),(name1, value3), ...)"""
 
-    def update(self):
+    def update():
         """Updates the metadata into the file passed as the output argument
            to the constructor. This method can't be called in streaming
            mode."""
 
-    def process(self, frames):
+    def process(frames):
         """Encode the frames passed as a numpy array, where columns are channels.
         
            In streaming mode the callback passed to the constructor is called whenever
            a block of encoded data is ready."""
 
-    def finish(self):
+    def finish():
         """Flush the encoded data and close the output file/stream. Calling this method
         may cause the streaming callback to be called if in streaming mode."""