django jwt token token

Use of jwt

jwt official website: https://jwt.io/

1.header

{‘alg’:‘HS256’, ‘typ’:‘JWT’}

2.payload

{ 'exp':xxx, # Expiration Time The timestamp of the expiration time of this token'iss':xxx, # (Issuer) Claim indicates the issuer of this token'aud':xxx, #(Audience) Claim indicates the token's 'iat':xxx, # (Issued At) Claim indicates the timestamp of the creation time'aud':xxx, # (Audience) Claim indicates that this token is issued for the group }

3.sign

HS256 (custom key, header after base64 +'.' + payload after base64)

jwt format

base64(header) + ‘.’ + base64(payload) + ‘.’ + base64(sign)

Code

import base64
import copy
import hmac
import json
import time


class Jwt(object):
    def __init__(self):
        pass

    @staticmethod
    def b64encode(content):
        # 去掉多余的 =号
        return base64.urlsafe_b64encode(content).replace(b'=', b'')

    @staticmethod
    def b64decode(b):
        # 把去掉的=号加回来
        sem = len(b) % 4
        if sem > 0:
            b += b'=' * (4 - sem)

        return base64.urlsafe_b64decode(b)

    # 编码
    @staticmethod
    def encode(payload, key, exp=300):

        # 初始化头 init header
        header = {
    
    'typ': 'JWT', 'alg': 'HS256'}

        header_json = json.dumps(header,
                                 separators=(',', ':'),  # 紧凑字符串
                                 sort_keys=True)  # 有序性

        header_bs = Jwt.b64encode(header_json.encode())

        # 初始化数据 init payload
        payload_self = copy.deepcopy(payload)
        if not isinstance(exp, int) and not isinstance(exp, str):
            raise TypeError('Exp must be int or str !')
        exp_time = time.time() + int(exp)
        print(exp_time)
        payload_self['exp'] = exp_time
        payload_js = json.dumps(payload_self,
                                separators=(',', ':'),  # 紧凑字符串
                                sort_keys=True)
        print(payload_js)
        # json => base64
        payload_bs = Jwt.b64encode(payload_js.encode())

        # 初始化签名 init sign
        if isinstance(key, str):
            key = key.encode()
        # 计算签名
        hm = hmac.new(key, header_bs + b'.' + payload_bs, digestmod='SHA256')
        # json => base64
        sign_bs = Jwt.b64encode(hm.digest())

        # 组合token
        return header_bs + b'.' + payload_bs + b'.' + sign_bs

    @staticmethod
    def decode(token, key):
        header_bs, payload_bs, sign_bs = token.split(b'.')
        # 校验签名
        if isinstance(key, str):
            key = key.encode()

        hm = hmac.new(key, header_bs + b'.' + payload_bs, digestmod='SHA256')
        print(sign_bs)
        print(Jwt.b64encode(hm.digest()))

        if Jwt.b64encode(hm.digest()) != sign_bs:
            print('签名校验失败！')
            raise

        # 检查 exp是否过期
        payload_js = Jwt.b64decode(payload_bs)
        payload = json.loads(payload_js)
        if 'exp' in payload:
            now = time.time()
            if now > payload['exp']:
                print('exp 校验失败')
                raise

        # return payload部分的解码
        return payload


if __name__ == '__main__':
    token = Jwt.encode({
    
    "username": "hzx"}, '12345', 300)
    print('生成token')
    print(token)
    print('校验结果')
    print(Jwt.decode(token, '12345'))

pyjwt

installation

pip install jwt

Use code

import time
import jwt

payload = {
    
    'username': 'hzx',
           'exp': time.time() + 2,  # 超时时间
           'iss': 'wo'}  # 发布者
token = jwt.encode(payload,
                   '123456',  # key
                   algorithm='HS256') # 加密算法
print(token, type(token))

a = jwt.decode(token,  # 令牌
               '123456',  # key
               algorithms='HS256',  # 加密算法
               issuer='wo')  # 校验发布者
print(a)

time.sleep(3)
# token过期 raise ExpiredSignatureError("Signature has expired")
# a = jwt.decode(token, '123456', algorithms='HS256')
# print(a)

Output result

eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJ1c2VybmFtZSI6Imh6eCIsImV4cCI6MTYxNDE1ODQyMC4zMTE2Mjk1LCJpc3MiOiJ3byJ9.9xm5N5w12c52DmXqw35WCZoBmzU8oyj8Pcx56XKhFiI 
<class 'str'>
{'username': 'hzx', 'exp': 1614158420.3116295, 'iss': 'wo'}