v0.2 Preview: Construction Plan.

backend/common/admin.py

@@ -0,0 +1,3 @@
+from django.contrib import admin
+
+# Register your models here.

backend/common/api.py

@@ -0,0 +1,18 @@
+from rest_framework.views import exception_handler as drf_exception_handler
+
+
+def exception_handler(exc, context):
+    response = drf_exception_handler(exc, context)
+    if response is None:
+        return response
+
+    request = context.get("request")
+    response.data = {
+        "error": {
+            "code": getattr(exc, "default_code", "request_error"),
+            "message": "请求未能完成",
+            "details": response.data,
+            "request_id": getattr(request, "request_id", None),
+        }
+    }
+    return response

backend/common/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class CommonConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'common'

backend/common/consumers.py

@@ -0,0 +1,17 @@
+from channels.generic.websocket import AsyncJsonWebsocketConsumer
+
+
+class HealthConsumer(AsyncJsonWebsocketConsumer):
+    group_name = "healthcheck"
+
+    async def connect(self):
+        try:
+            await self.channel_layer.group_add(self.group_name, self.channel_name)
+            await self.channel_layer.group_discard(self.group_name, self.channel_name)
+        except Exception:
+            await self.close(code=1011)
+            return
+
+        await self.accept()
+        await self.send_json({"status": "ok", "channel_layer": "ok"})
+        await self.close()

backend/common/logging.py

@@ -0,0 +1,11 @@
+import contextvars
+import logging
+
+
+request_id_context = contextvars.ContextVar("request_id", default="-")
+
+
+class RequestIDFilter(logging.Filter):
+    def filter(self, record):
+        record.request_id = request_id_context.get()
+        return True

backend/common/management/__init__.py

@@ -0,0 +1 @@
+

backend/common/management/commands/__init__.py

@@ -0,0 +1 @@
+

backend/common/management/commands/check_mysql.py

@@ -0,0 +1,63 @@
+import re
+
+from django.core.management.base import BaseCommand, CommandError
+from django.db import connection
+
+
+MINIMUM_VERSION = (8, 0, 35)
+
+
+class Command(BaseCommand):
+    help = "检查生产 MySQL 的版本、字符集、引擎、严格模式和事务隔离级别"
+
+    def handle(self, *args, **options):
+        if connection.vendor != "mysql":
+            raise CommandError(f"数据库必须是 MySQL，当前为 {connection.vendor}")
+
+        with connection.cursor() as cursor:
+            cursor.execute(
+                """
+                SELECT VERSION(),
+                       @@character_set_server,
+                       @@collation_server,
+                       @@sql_mode,
+                       @@transaction_isolation,
+                       @@default_storage_engine
+                """
+            )
+            (
+                version_text,
+                charset,
+                collation,
+                sql_mode,
+                isolation,
+                storage_engine,
+            ) = cursor.fetchone()
+
+        match = re.match(r"^(\d+)\.(\d+)\.(\d+)", version_text)
+        if match is None:
+            raise CommandError(f"无法解析 MySQL 版本: {version_text}")
+        version = tuple(int(part) for part in match.groups())
+        if version < MINIMUM_VERSION:
+            minimum = ".".join(str(part) for part in MINIMUM_VERSION)
+            raise CommandError(f"MySQL 版本过低: {version_text}，最低要求 {minimum}")
+        if charset.lower() != "utf8mb4":
+            raise CommandError(f"character_set_server 必须是 utf8mb4，当前为 {charset}")
+        if not collation.lower().startswith("utf8mb4_"):
+            raise CommandError(f"collation_server 必须属于 utf8mb4，当前为 {collation}")
+
+        modes = {mode.strip().upper() for mode in sql_mode.split(",")}
+        if not {"STRICT_TRANS_TABLES", "STRICT_ALL_TABLES"} & modes:
+            raise CommandError(f"MySQL 未启用严格模式: {sql_mode}")
+        if isolation.upper().replace("_", "-") != "READ-COMMITTED":
+            raise CommandError(f"事务隔离级别必须是 READ-COMMITTED，当前为 {isolation}")
+        if storage_engine.lower() != "innodb":
+            raise CommandError(f"默认存储引擎必须是 InnoDB，当前为 {storage_engine}")
+
+        self.stdout.write(
+            self.style.SUCCESS(
+                "MySQL 检查通过: "
+                f"version={version_text}, charset={charset}, "
+                f"collation={collation}, isolation={isolation}, engine={storage_engine}"
+            )
+        )

backend/common/middleware.py

@@ -0,0 +1,19 @@
+import uuid
+
+from .logging import request_id_context
+
+
+class RequestIDMiddleware:
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        request_id = request.headers.get("X-Request-ID") or str(uuid.uuid4())
+        request.request_id = request_id
+        token = request_id_context.set(request_id)
+        try:
+            response = self.get_response(request)
+            response["X-Request-ID"] = request_id
+            return response
+        finally:
+            request_id_context.reset(token)

backend/common/models.py

@@ -0,0 +1,3 @@
+from django.db import models
+
+# Create your models here.

backend/common/tests.py

@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.

backend/common/views.py

@@ -0,0 +1,14 @@
+from django.db import connection
+from django.http import JsonResponse
+from django.shortcuts import render
+
+
+def home(request):
+    return render(request, "index.html")
+
+
+def health(request):
+    with connection.cursor() as cursor:
+        cursor.execute("SELECT 1")
+        cursor.fetchone()
+    return JsonResponse({"status": "ok", "database": "ok"})