调用动态数据库的 aws Lambda put_item给出了语法错误

Question

我用Python创建了我的第一个Lambda，以在名为Users的DynamoDB表中创建一个新条目，该表具有String类型的分区键UserId。我使用API网关中的POST方法调用它，使用测试函数发送请求体：

{
    "email":"testemail",
    "name":"testname testerson",
    "password":"testpassword1"
}

该方法背后的想法是生成一个 UUID 以用于主键，并且在它已被使用时，再次生成它，直到它是唯一的。lambda 函数为：

def create_user(event, context):
    status_code = 0
    response = ''
    body = event['body']
    
    # check all required fields are present
    if all(key in body.keys() for key in ['email', 'password', 'name']):
        # generate salt and hashed password
        salt = bcrypt.gensalt()
        hashed = bcrypt.hashpw(body['password'], salt)
        
        # get users table from dynamodb
        dynamodb = boto3.resource('dynamodb')
        table = dynamodb.Table('Users')
        
        inserted = False
        while not inserted:
            user_id = uuid.uuid4().hex
            try:
                response = table.put_item(
                    Item={
                        'UserId' = user_id,
                        'name' = body['name'],
                        'email' = body['email'],
                        'password' = hashed,
                        'salt' = salt
                    },
                    ConditionExpression = 'attribute_not_exists(UserId)'
                )
            except Exception as e:
                if e.response['Error']['Code'] == "ConditionalCheckFailedException":
                    continue
                status_code = 500
                response = 'Could not process your request'
                break
            else:
                status_code = 200
                response = 'Account successfully created'
                inserted = True
    else:
        status_code = 400
        response = 'Malformed request'
    
    return {
        'statusCode': status_code,
        'body': json.dumps(response)
    }

语法错误出现在包含“UserId”=user_id的行的日志中，但我不知道为什么。

任何帮助都将不胜感激！

Answer 1

有两种定义字典文字的标准方法

Item={
    'UserId' = user_id,
    'name' = body['name'],
    'email' = body['email'],
    'password' = hashed,
    'salt' = salt
}

这不是其中之一。

您可以这样做：

Item={
    'UserId': user_id,
    'name': body['name'],
    'email': body['email'],
    'password': hashed,
    'salt': salt
}

或者:

Item=dict(
    UserId=user_id,
    name=body['name'],
    email=body['email'],
    password=hashed,
    salt=salt
}