[TD-228] fix python connector to support binary interface change

src/connector/python/linux/python3/taos/cinterface.py

@@ -146,6 +146,7 @@ class CTaosInterface(object):
     libtaos.taos_errstr.restype = ctypes.c_char_p
     libtaos.taos_subscribe.restype = ctypes.c_void_p
     libtaos.taos_consume.restype = ctypes.c_void_p
+    libtaos.taos_fetch_lengths.restype = ctypes.c_void_p
 
     def __init__(self, config=None):
         '''
@@ -314,6 +315,8 @@ class CTaosInterface(object):
 
         isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
         blocks = [None] * len(fields)
+        fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
+        fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
         for i in range(len(fields)):
             data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
             if data == None:
@@ -323,7 +326,7 @@ class CTaosInterface(object):
             if fields[i]['type'] not in _CONVERT_FUNC:
                 raise DatabaseError("Invalid data type returned from database")
             
-            blocks[i] = _CONVERT_FUNC[fields[i]['type']](data, num_of_rows, fields[i]['bytes'], isMicro)
+            blocks[i] = _CONVERT_FUNC[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
 
         return blocks, abs(num_of_rows)