feat(document): add data_uri2blob converter

jina/drivers/convertdriver.py

@@ -33,54 +33,70 @@ def _apply_all(
 
 class URI2Buffer(ConvertDriver):
     """Driver to convert URI to buffer"""
+
     def __init__(self, convert_fn: str = 'convert_uri_to_buffer', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class URI2DataURI(ConvertDriver):
     """Driver to convert URI to data URI
     """
+
     def __init__(self, convert_fn: str = 'convert_uri_to_data_uri', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class Buffer2URI(ConvertDriver):
     """Driver to convert buffer to URI
     """
+
     def __init__(self, convert_fn: str = 'convert_buffer_to_uri', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class BufferImage2Blob(ConvertDriver):
     """Driver to convert image buffer to blob
     """
+
     def __init__(self, convert_fn: str = 'convert_buffer_image_to_blob', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class URI2Blob(ConvertDriver):
     """Driver to convert URI to blob
     """
+
     def __init__(self, convert_fn: str = 'convert_uri_to_blob', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
+class DataURI2Blob(ConvertDriver):
+    """Driver to convert Data URI to image blob
+    """
+
+    def __init__(self, convert_fn: str = 'convert_data_uri_to_blob', *args, **kwargs):
+        super().__init__(convert_fn, *args, **kwargs)
+
+
 class Text2URI(ConvertDriver):
     """Driver to convert text to URI
     """
+
     def __init__(self, convert_fn: str = 'convert_text_to_uri', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class URI2Text(ConvertDriver):
     """Driver to convert URI to text
     """
+
     def __init__(self, convert_fn: str = 'convert_uri_to_text', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)
 
 
 class Blob2PngURI(ConvertDriver):
     """Driver to convert blob to URI
     """
+
     def __init__(self, convert_fn: str = 'convert_blob_to_uri', *args, **kwargs):
         super().__init__(convert_fn, *args, **kwargs)

jina/types/document/__init__.py

@@ -510,7 +510,7 @@ def buffer(self) -> bytes:
     def buffer(self, value: bytes):
         """Set the ``buffer`` to :param:`value`."""
         self._pb_body.buffer = value
-        if value:
+        if value and not self._pb_body.mime_type:
             with ImportExtensions(required=False,
                                   pkg_name='python-magic',
                                   help_text=f'can not sniff the MIME type '
@@ -685,6 +685,17 @@ def convert_uri_to_blob(self, color_axis: int = -1, uri_prefix: str = None, **kw
         """
         self.blob = to_image_blob((uri_prefix + self.uri) if uri_prefix else self.uri, color_axis)
 
+    def convert_data_uri_to_blob(self, color_axis: int = -1, **kwargs):
+        """ Convert data URI to image blob
+
+        :param color_axis: the axis id of the color channel, ``-1`` indicates the color channel info at the last axis
+        :param kwargs: reserved for maximum compatibility when using with ConvertDriver
+        """
+        req = urllib.request.Request(self.uri, headers={'User-Agent': 'Mozilla/5.0'})
+        with urllib.request.urlopen(req) as fp:
+            buffer = fp.read()
+        self.blob = to_image_blob(io.BytesIO(buffer), color_axis)
+
     def convert_uri_to_buffer(self, **kwargs):
         """Convert uri to buffer
         Internally it downloads from the URI and set :attr:`buffer`.