reclosedev · December 19, 2015 07:49 · Jul 3, 2013 · Jul 3, 2013 · Jul 3, 2013
diff --git a/remote_file.py b/remote_file.py
@@ -15,7 +15,6 @@ def __init__(self, url, session=None):
         self.total_bytes_downloaded = 0
         self._ensure_ranges_supported()
 
-
     def _ensure_ranges_supported(self):
         try:
             r = self._session.get(self._url, stream=True)
@@ -26,7 +25,7 @@ def _ensure_ranges_supported(self):
             raise IOError("Unknown Content-Length")
         if not 'bytes' in r.headers.get('Accept-Ranges', ''):
             raise IOError("Doesn't accept ranges")
-        self._size = int(size)
+        self._bytes_in_stream_left = self._size = int(size)
         self._response = r
 
     def seek(self, offset, whence=0):
@@ -43,7 +42,8 @@ def tell(self):
         return self._position
 
     def read(self, size=None):
-        if self._bytes_in_stream_left and self._stream_position == self._position:
+        if (self._bytes_in_stream_left
+                and self._stream_position == self._position):
             return self._read_stream(size)
         self._stream_position = self._position
         end = self._size if size is None else self._position + size

diff --git a/remote_file.py b/remote_file.py
@@ -11,8 +11,10 @@ def __init__(self, url, session=None):
         self._response = None
         self._position = 0
         self._stream_position = 0
-        self._ensure_ranges_supported()
+        self._bytes_in_stream_left = 0
         self.total_bytes_downloaded = 0
+        self._ensure_ranges_supported()
+
 
     def _ensure_ranges_supported(self):
         try:
@@ -41,12 +43,13 @@ def tell(self):
         return self._position
 
     def read(self, size=None):
-        if self._stream_position == self._position:
+        if self._bytes_in_stream_left and self._stream_position == self._position:
             return self._read_stream(size)
         self._stream_position = self._position
         end = self._size if size is None else self._position + size
         if end > self._size:
             return ''
+        self._bytes_in_stream_left = end - self._position
         headers = {'Range': 'bytes=%s-%s' % (self._position, end)}
         r = self._session.get(self._url, stream=True, headers=headers)
         if self._response:
@@ -59,6 +62,7 @@ def _read_stream(self, size=None):
         received = len(data)
         self._position += received
         self._stream_position += received
+        self._bytes_in_stream_left -= received
         self.total_bytes_downloaded += received
         return data
 

diff --git a/remote_file.py b/remote_file.py
@@ -0,0 +1,83 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+import requests
+
+
+class RemoteFile(object):
+    def __init__(self, url, session=None):
+        self._url = url
+        self._session = session or requests.Session()
+        self._need_to_close_session = session is None
+        self._response = None
+        self._position = 0
+        self._stream_position = 0
+        self._ensure_ranges_supported()
+        self.total_bytes_downloaded = 0
+
+    def _ensure_ranges_supported(self):
+        try:
+            r = self._session.get(self._url, stream=True)
+        except Exception as e:
+            raise IOError(e)
+        size = r.headers['Content-Length']
+        if not size:
+            raise IOError("Unknown Content-Length")
+        if not 'bytes' in r.headers.get('Accept-Ranges', ''):
+            raise IOError("Doesn't accept ranges")
+        self._size = int(size)
+        self._response = r
+
+    def seek(self, offset, whence=0):
+        if whence == 0:
+            self._position = offset
+        if whence == 1:
+            self._position += offset
+        elif whence == 2:
+            self._position = self._size + offset
+        if not (0 <= self._position <= self._size):
+            raise IOError("Out of bounds")
+
+    def tell(self):
+        return self._position
+
+    def read(self, size=None):
+        if self._stream_position == self._position:
+            return self._read_stream(size)
+        self._stream_position = self._position
+        end = self._size if size is None else self._position + size
+        if end > self._size:
+            return ''
+        headers = {'Range': 'bytes=%s-%s' % (self._position, end)}
+        r = self._session.get(self._url, stream=True, headers=headers)
+        if self._response:
+            self._response.close()
+        self._response = r
+        return self._read_stream(size)
+
+    def _read_stream(self, size=None):
+        data = self._response.raw.read(size)
+        received = len(data)
+        self._position += received
+        self._stream_position += received
+        self.total_bytes_downloaded += received
+        return data
+
+    def close(self):
+        if self._response:
+            self._response.close()
+        if self._need_to_close_session:
+            self._session.close()
+
+    def __del__(self):
+        self.close()
+
+# TODO tests
+# TODO docstrings
+if __name__ == '__main__':
+    import zipfile
+    #url = 'http://mirror.yandex.ru/mirrors/ftp.mysql.com/Downloads/MySQL-6.0/mysql-6.0.11-alpha.zip'
+    url = 'http://mirror.yandex.ru/mirrors/ftp.mysql.com/Downloads/Connector-Python/mysql-connector-python-1.0.10.zip'
+    rf = RemoteFile(url)
+    archive = zipfile.ZipFile(rf)
+    archive.printdir()
+    print 'Size:', rf._size, 'Downloaded:', rf.total_bytes_downloaded