关于msgpack报错： ExtraData: unpack(b) received extra data.

Question

问题遇到的现象和发生背景

我有多个msgpack文件，把他们组合在一起后，就打不开了。

组合多个msgpack

import msgpack
with open('/home/suned/data/giscup_2021_1/totalmsgpack/total.msgpack','wb') as f1:
    for i in range(1,32):
        file_name = f"202008{i:02}.msgpack"
        with open(f'/home/suned/data/giscup_2021_1/msgpack/{file_name}','rb') as f2:
            unpacked = msgpack.unpackb(f2.read())
            msgpack.dump(unpacked,f1)

想要反序列化组合后的文件（total.msgpack）

import msgpack
with open('/home/suned/data/giscup_2021_1/totalmsgpack/total.msgpack', 'rb') as f1:
    dct1 = msgpack.unpackb(f1.read())
    print(dct1)

报错

ExtraData                                 Traceback (most recent call last)
/tmp/ipykernel_85730/2692480189.py in <module>
      1 import msgpack
      2 with open('/home/suned/data/giscup_2021_1/totalmsgpack/total.msgpack', 'rb') as f1:
----> 3     dct1 = msgpack.unpackb(f1.read())
      4     print(dct1)

msgpack/_unpacker.pyx in msgpack._cmsgpack.unpackb()

ExtraData: unpack(b) received extra data.

但是组合前的单个msgpack是可以打开的，比如打开20200801.msgpack

with open('/home/suned/data/giscup_2021_1/msgpack/20200801.msgpack', 'rb') as f2:
    dct2 = msgpack.unpackb(f2.read())
    print(dct2)

我的想法

单个msgpack做unpackb后的结构是一个列表，列表里面包含多个字典结构，类似
[{'order_id': 5966280.0, 'eta': 531.0, 'dist': 2923.0, 'simple_eta': 495.0, 'driver_id': 75457.0, 'slice_id': 153.0}，{'order_id': 6099942.0, 'eta': 590.0, 'dist': 3212.278, 'simple_eta': 559.0, 'driver_id': 19210.0, 'slice_id': 157.0}...]
是不是做了组合后，totalmsgpack里面包含了多个列表结构，所以出现了这个错误呢？（received extra data）
弄了一天了，没能解决呀，头疼。

Answer 1

估计就是你说的问题。 一个标准的 msgpack 文件是只有1个字典列表？
就是这种形式

[{},{},{}]

你现在合并后，变成这种形式

[{},{},{}]
[{},{},{}]
[{},{},{}]

是这样吧？