Attempt

archive.py

@@ -136,16 +136,16 @@ def zip_local_file_header(filename: str, filepath: str) -> bytes:
     buffer[12:14] = mtime.day | (mtime.month << 5) | ((mtime.year - 1980) << 9)
 
     # Field 6: crc-32 of uncompressed data (buffer[14:18])
-    buffer[14:18] = crc32(filepath).to_bytes(4)
+    buffer[14:18] = crc32(filepath).to_bytes(4, byteorder='little')
 
     # Field 7: compressed size (buffer[18:22])
-    buffer[18:22] = stat.st_size.to_bytes(4)
+    buffer[18:22] = stat.st_size.to_bytes(4, byteorder='little')
 
     # Field 8: uncompressed size (buffer[22:26])
-    buffer[22:26] = stat.st_size.to_bytes(4)
+    buffer[22:26] = stat.st_size.to_bytes(4, byteorder='little')
 
     # Field 9: filename length (buffer[26:28])
-    buffer[26:28] = len(filename).to_bytes(4)
+    buffer[26:28] = len(filename).to_bytes(2, byteorder='little')
 
     # Field 10: extra field length (buffer[28:30])
 
@@ -155,7 +155,7 @@ def zip_local_file_header(filename: str, filepath: str) -> bytes:
     return buffer
 
 
-def zip_central_directory_file_header(filename: str, filepath: str) -> bytes:
+def zip_central_directory_file_header(filename: str, filepath: str, offset: int) -> bytes:
     buffer_size = 46 + len(filename)
     buffer = bytearray(buffer_size)
     stat = os.stat(filepath)
@@ -179,16 +179,16 @@ def zip_central_directory_file_header(filename: str, filepath: str) -> bytes:
     buffer[14:16] = mtime.day | (mtime.month << 5) | ((mtime.year - 1980) << 9)
 
     # Field 6: crc-32 of uncompressed data (buffer[16:20])
-    buffer[16:20] = crc32(filepath).to_bytes(4)
+    buffer[16:20] = crc32(filepath).to_bytes(4, byteorder='little')
 
     # Field 7: compressed size (buffer[20:24])
-    buffer[20:24] = stat.st_size.to_bytes(4)
+    buffer[20:24] = stat.st_size.to_bytes(4, byteorder='little')
 
     # Field 8: uncompressed size (buffer[24:28])
-    buffer[24:28] = stat.st_size.to_bytes(4)
+    buffer[24:28] = stat.st_size.to_bytes(4, byteorder='little')
 
     # Field 9: filename length (buffer[28:30])
-    buffer[28:30] = len(filename).to_bytes(4)
+    buffer[28:30] = len(filename).to_bytes(2, byteorder='little')
 
     # Field 10: extra field length (buffer[30:32])
 
@@ -208,11 +208,45 @@ def zip_central_directory_file_header(filename: str, filepath: str) -> bytes:
     return buffer
 
 
+def zip_end_of_central_directory(items_number: int, central_directory_size: int, central_directory_offset: int):
+    buffer = bytearray(22)
+    # Field 1: End of central directory signature = 0x06054b50 (buffer[0:4])
+    buffer[0:4] = b'\x06\x05\x4b\x50'
+
+    # Field 2: Number of this disk (buffer[4:6])
+
+    # Field 3: Disk where central directory starts (buffer[6:8])
+
+    # Field 4: Number of central directory records on this disk (buffer[8:10])
+    buffer[8:10] = items_number.to_bytes(2, byteorder='little')
+
+    # Field 5: Total number of central directory records (buffer[10:12])
+    buffer[10:12] = items_number.to_bytes(2, byteorder='little')
+
+    # Field 6: Size of central directory in bytes (buffer[12:16])
+    buffer[12:16] = central_directory_size.to_bytes(4, byteorder='little')
+
+    # Field 7: Offset of start of central directory (buffer[16:20])
+    buffer[16:20] = central_directory_size.to_bytes(4, byteorder='little')
+
+    # Field 8: Comment length (buffer[20:22])
+
+    # Field 9: Comment (buffer[22:])
+    return buffer
+
+
 class ZipSender(ArchiveSender):
     def response(self):
         def generate():
+            local_offsets = dict()
+            current_byte = 0
+
             for name, file in self.files.items():
-                yield zip_local_file_header(name, file)
+                local_offsets[name] = current_byte
+                chunk = zip_local_file_header(name, file)
+                current_byte += chunk
+
+                yield chunk
 
                 with open(file, 'rb') as f:
                     while True:
@@ -221,8 +255,20 @@ class ZipSender(ArchiveSender):
                         if len(bytes) == 0:
                             break
 
+                        current_byte += len(bytes)
                         yield bytes
 
+            central_directory_size = 0
+            centra_directory_offset = current_byte
+
+            for name, file, in self.files.items():
+                chunk = zip_central_directory_file_header(name, file, local_offsets[name])
+                central_directory_size += len(chunk)
+                current_byte += len(chunk)
+                yield chunk
+
+            yield zip_end_of_central_directory(len(self.files.items()), central_directory_size, centra_directory_offset)
+
         return Response(
             generate(),
             mimetype='application/zip',