Canonical serialization

This was discussed here back in 2016 https://github.com/msgpack/msgpack/issues/215

Does pyserde have a repeatable serialization that could be fed to hashlib?

import hashlib

from datetime import datetime
from typing import Optional
from dataclasses import dataclass
from serde import serialize
from serde.msgpack import to_msgpack

@serialize
@dataclass
class Entry:
    feed_url: str
    id: str
    updated: Optional[datetime] = None

e = []
for i in range(3):
    entry = Entry('feed one', 'id', datetime(i+1, i+1, i+1))
    e.append(entry)

for i in range(3):
    for j in range(3):
        print(hashlib.sha256(to_msgpack(e[j])).hexdigest())

seems repeatable. But I haven’t tested it across platforms.

Also see:

https://death.andgravity.com/stable-hashing where json was used https://github.com/yuan-xy/canoser-python where dataclasses could be used, but are not.

[adsharma]

Yes, Thanks for the feedback.

[adsharma]

• In my modeling of network messages, there is rarely a dict in the message. Even if there is, it could be modeled as two vectors.
• Re: representing the number -20 in many different ways, we just need to use pyserde as a reference implementation and say, -20 is to be represented as EC. Works for me 😃
• Yes, like serde_skip better.
• JSON: msgpack is more compact and probably faster to parse.