github.py

# Copyright 2025 AptS-1547
# 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.

"""
GitHub Webhook 处理模块
本模块用于处理 GitHub Webhook 事件，包括验证签名、查找匹配的 webhook 配置和提取 push 事件数据。
作者：AptS:1547
版本：0.1.0-alpha
日期：2025-04-17
本程序遵循 Apache License 2.0 许可证
"""

import hmac
import hashlib
import logging
from typing import Optional, Dict, Any, List

from fastapi import Request, HTTPException, Header

from app.utils.matching import match_pattern

logger = logging.getLogger(__name__)

async def verify_signature(
        request: Request,
        webhooks: List,
        x_hub_signature_256: Optional[str] = Header(None)
        ) -> bool:
    """验证 GitHub webhook 签名"""

    try:
        body = await request.body()
        payload = await request.json()
        repo_name = payload.get("repository", {}).get("full_name")
    except Exception as e:
        logger.error("解析请求体失败: %s", str(e))
        raise HTTPException(
            status_code=400, detail="Invalid JSON payload") from e

    webhook_secret = None
    for webhook in webhooks:
        if any(match_pattern(repo_name, repo_pattern) for repo_pattern in webhook.REPO):
            webhook_secret = webhook.SECRET
            break

    if not webhook_secret:
        logger.warning("仓库 %s 未配置 webhook 密钥，跳过签名验证", repo_name)
        return True

    if not x_hub_signature_256:
        raise HTTPException(
            status_code=401, detail="Missing X-Hub-Signature-256 header")

    signature = hmac.new(
        key=webhook_secret.encode(),
        msg=body,
        digestmod=hashlib.sha256
    ).hexdigest()

    expected_signature = f"sha256={signature}"
    if not hmac.compare_digest(expected_signature, x_hub_signature_256):
        raise HTTPException(status_code=401, detail="Invalid signature")

    return True

def find_matching_webhook(
        repo_name: str,
        branch: str,
        event_type: str,
        webhooks: List
        ) -> Optional[Any]:
    """
    查找匹配的 webhook 配置

    Args:
        repo_name: 仓库名
        branch: 分支名
        event_type: 事件类型
        webhooks: webhook 配置列表

    Returns:
        匹配的 webhook 配置或 None
    """
    for webhook in webhooks:
        # 检查仓库名是否匹配配置中的任一模式
        repo_matches = any(match_pattern(repo_name, repo_pattern)
                          for repo_pattern in webhook.REPO)

        # 检查分支名是否匹配配置中的任一模式
        branch_matches = any(match_pattern(branch, branch_pattern)
                            for branch_pattern in webhook.BRANCH)

        # 检查事件类型是否匹配
        if (repo_matches and branch_matches and event_type in webhook.EVENTS):
            return webhook

    return None


def extract_push_data(payload: Dict[str, Any]) -> Dict[str, Any]:
    """
    从 push 事件中提取相关数据

    Args:
        payload: GitHub webhook 负载

    Returns:
        包含提取数据的字典
    """
    return {
        "repo_name": payload.get("repository", {}).get("full_name"),
        "branch": payload.get("ref", "").replace("refs/heads/", ""),
        "pusher": payload.get("pusher", {}).get("name"),
        "commits": payload.get("commits", []),
        "commit_count": len(payload.get("commits", []))
    }