Thrift（Python）中的编码列表

Question

我想知道什么是用ThriftPy对结构列表进行二进制编码的最佳方法。我发现的唯一方法是创建另一个包装struct并从流中删除二进制前缀/后缀，但这是非常hacky，应该肯定有更好的方法。

foobar.thrift：

struct Object { 
    1: i32 num1 = 0, 
    2: i32 num2, 
} 

struct ListContainer { 
    1: list<Object> objects 
} 

app.py

foobar = thriftpy.load('foobar.thrift', module_name="foobar_thrift") 

objects = [ ... list of Objects ... ] 

thrift_obj = foobar.ListContainer(objects) 

trans = TMemoryBuffer() 
thrift_obj.write(TBinaryProtocol(trans)) 

encoded_list = bytes(trans.getvalue())[3:-1] 

Answer 1

我找到了解决办法...不是特别优雅，但比以前更好。

foobar.thrift：

struct Object { 
    1: i32 num1 = 0, 
    2: i32 num2, 
} 

typedef list<Object> ObjectList 

app.py：

import thriftpy 
from thriftpy.transport import TMemoryBuffer 
from thriftpy.protocol.binary import write_val 


foobar = thriftpy.load('foobar.thrift') 


def write_list(trans, val, list_type): 
    ttype, spec = list_type 
    write_val(trans, ttype, val, spec=spec) 

val = [foobar.Object(num1=8, num2=12)] 

trans = TMemoryBuffer() 
write_list(trans, val, foobar.ObjectList) 
encoded_list = bytes(trans.getvalue()) 

我想看到标准节俭实现做什么。它并没有让它变得更容易。它不会产生对ObjectList东西所以为了达到同样的，你需要做的thrift -gen py foobar.thrift，然后：

app.py：

import sys 
sys.path.append('gen-py') 

from foobar.ttypes import * 
from thrift.protocol import TBinaryProtocol 
from thrift.transport import TTransport 


def write_list(trans, val): 
    protocol = TBinaryProtocol.TBinaryProtocol(trans) 
    protocol.writeListBegin(TType.STRUCT, len(val)) 
    for values in val: 
     values.write(protocol) 
    protocol.writeListEnd() # This is a nop 

val = [Object(num1=8, num2=12)] 

trans = TTransport.TMemoryBuffer() 
write_list(trans, val) 
encoded_list = trans.getvalue()