add Python .write_to_buffer()

now we need to be able to get the bytes from a VipsBlob

TODO

@@ -1,6 +1,9 @@
 
 - python:
 
+	- try6 produces a VipsBlob object ... need to turn this into a Python
+	  buffer, or whatever they are called now
+
 	- add more constructors
 
 	- need more writers

python/try6.py

@@ -0,0 +1,13 @@
+#!/usr/bin/python
+
+import sys
+
+import logging
+logging.basicConfig(level = logging.DEBUG)
+
+from gi.repository import Vips 
+from vips8 import vips
+
+a = Vips.Image.new_from_file(sys.argv[1])
+
+a.write_to_buffer(".jpg")

python/vips8/vips.py

@@ -207,6 +207,16 @@ def vips_image_write_to_file(self, vips_filename, **kwargs):
 
     _call_base(saver, [filename], kwargs, self, option_string)
 
+def vips_image_write_to_buffer(self, vips_filename, **kwargs):
+    filename = Vips.filename_get_filename(vips_filename)
+    option_string = Vips.filename_get_options(vips_filename)
+    saver = Vips.Foreign.find_save_buffer(filename)
+    if saver == None:
+        raise Error('No known saver for "%s".' % filename)
+    logging.debug('Image.write_to_buffer: saver = %s' % saver)
+
+    return _call_base(saver, [], kwargs, self, option_string)
+
 # apply a function to a thing, or map over a list
 # we often need to do something like (1.0 / other) and need to work for lists
 # as well as scalars
@@ -319,6 +329,8 @@ setattr(Vips.Image, 'new_from_file', classmethod(vips_image_new_from_file))
 
 # instance methods
 Vips.Image.write_to_file = vips_image_write_to_file
+Vips.Image.write_to_buffer = vips_image_write_to_buffer
+
 Vips.Image.__getattr__ = vips_image_getattr
 Vips.Image.__add__ = vips_add
 Vips.Image.__radd__ = vips_add