Updated DB_Helper by adding firebase methods.

venv/Lib/site-packages/gcloud/streaming/stream_slice.py

@@ -0,0 +1,70 @@
+"""Small helper class to provide a small slice of a stream."""
+
+from six.moves import http_client
+
+
+class StreamSlice(object):
+    """Provides a slice-like object for streams.
+
+    :type stream:  readable file-like object
+    :param stream:  the stream to be buffered
+
+    :type max_bytes: integer
+    :param max_bytes: maximum number of bytes to return in the slice
+    """
+    def __init__(self, stream, max_bytes):
+        self._stream = stream
+        self._remaining_bytes = max_bytes
+        self._max_bytes = max_bytes
+
+    def __repr__(self):
+        return 'Slice of stream %s with %s/%s bytes not yet read' % (
+            self._stream, self._remaining_bytes, self._max_bytes)
+
+    def __len__(self):
+        return self._max_bytes
+
+    def __nonzero__(self):
+        # For 32-bit python2.x, len() cannot exceed a 32-bit number; avoid
+        # accidental len() calls from httplib in the form of "if this_object:".
+        return bool(self._max_bytes)
+
+    @property
+    def length(self):
+        """Maximum number of bytes to return in the slice.
+
+        .. note::
+
+           For 32-bit python2.x, len() cannot exceed a 32-bit number.
+
+        :rtype: integer
+        """
+        return self._max_bytes
+
+    def read(self, size=None):
+        """Read bytes from the slice.
+
+        Compared to other streams, there is one case where we may
+        unexpectedly raise an exception on read: if the underlying stream
+        is exhausted (i.e. returns no bytes on read), and the size of this
+        slice indicates we should still be able to read more bytes, we
+        raise :exc:`IncompleteRead`.
+
+        :type size: integer or None
+        :param size: If provided, read no more than size bytes from the stream.
+
+        :rtype: bytes
+        :returns: bytes read from this slice.
+
+        :raises: :exc:`IncompleteRead`
+        """
+        if size is not None:
+            read_size = min(size, self._remaining_bytes)
+        else:
+            read_size = self._remaining_bytes
+        data = self._stream.read(read_size)
+        if read_size > 0 and not data:
+            raise http_client.IncompleteRead(
+                self._max_bytes - self._remaining_bytes, self._max_bytes)
+        self._remaining_bytes -= len(data)
+        return data