# -*- coding: utf-8 -*-

# MinIO Python Library for Amazon S3 Compatible Cloud Storage, (C)

# 2020 MinIO, Inc.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

# http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

"""Request/response of PutBucketEncryption and GetBucketEncryption APIs."""

from __future__ import absolute_import, annotations

from abc import ABC

from dataclasses import dataclass

from typing import Optional, Type, TypeVar, cast

from xml.etree import ElementTree as ET

from .xml import Element, SubElement, find, findtext

AES256 = "AES256"

AWS_KMS = "aws:kms"

A = TypeVar("A", bound="Rule")

@dataclass(frozen=True)

class Rule(ABC):

"""Server-side encryption rule. """

sse_algorithm: str

kms_master_key_id: Optional[str] = None

@classmethod

def new_sse_s3_rule(cls: Type[A]) -> A:

"""Create SSE-S3 rule."""

return cls(sse_algorithm=AES256)

@classmethod

def new_sse_kms_rule(

cls: Type[A],

kms_master_key_id: Optional[str] = None,

) -> A:

"""Create new SSE-KMS rule."""

return cls(sse_algorithm=AWS_KMS, kms_master_key_id=kms_master_key_id)

@classmethod

def fromxml(cls: Type[A], element: ET.Element) -> A:

"""Create new object with values from XML element."""

element = cast(

ET.Element,

find(element, "ApplyServerSideEncryptionByDefault", True),

)

return cls(

sse_algorithm=cast(str, findtext(element, "SSEAlgorithm", True)),

kms_master_key_id=findtext(element, "KMSMasterKeyID"),

)

def toxml(self, element: Optional[ET.Element]) -> ET.Element:

"""Convert to XML."""

if element is None:

raise ValueError("element must be provided")

element = SubElement(element, "Rule")

tag = SubElement(element, "ApplyServerSideEncryptionByDefault")

SubElement(tag, "SSEAlgorithm", self.sse_algorithm)

if self.kms_master_key_id is not None:

SubElement(tag, "KMSMasterKeyID", self.kms_master_key_id)

return element

B = TypeVar("B", bound="SSEConfig")

@dataclass(frozen=True)

class SSEConfig:

"""server-side encryption configuration."""

rule: Rule

def __post_init__(self):

if not self.rule:

raise ValueError("rule must be provided")

@classmethod

def fromxml(cls: Type[B], element: ET.Element) -> B:

"""Create new object with values from XML element."""

element = cast(ET.Element, find(element, "Rule", True))

return cls(Rule.fromxml(element))

def toxml(self, element: Optional[ET.Element]) -> ET.Element:

"""Convert to XML."""

element = Element("ServerSideEncryptionConfiguration")

self.rule.toxml(element)

return element