feat(msg): 完整实现 msg 消息服务

包含 channels/preferences/templates/grpc/kafka/outbox/push/redis 等完整实现

services/msg/src/shared/errors/application-error.ts

@@ -1,11 +1,11 @@
 export type ErrorType =
-  | 'validation'
-  | 'not_found'
-  | 'permission_denied'
-  | 'conflict'
-  | 'business'
-  | 'database'
-  | 'internal';
+  | "validation"
+  | "not_found"
+  | "permission_denied"
+  | "conflict"
+  | "business"
+  | "database"
+  | "internal";
 
 export interface ErrorDetails {
   [key: string]: unknown;
@@ -40,57 +40,135 @@ export abstract class ApplicationError extends Error {
 }
 
 export class ValidationError extends ApplicationError {
-  readonly type = 'validation' as const;
+  readonly type = "validation" as const;
   readonly statusCode = 400;
   constructor(message: string, details?: ErrorDetails) {
-    super(message, 'MSG_VALIDATION_ERROR', details);
+    super(message, "MSG_VALIDATION_ERROR", details);
   }
 }
 
 export class NotFoundError extends ApplicationError {
-  readonly type = 'not_found' as const;
+  readonly type = "not_found" as const;
   readonly statusCode = 404;
   constructor(resource: string, id: string) {
-    super(`${resource} not found: ${id}`, 'MSG_NOT_FOUND', { resource, id });
+    super(`${resource} not found: ${id}`, "MSG_NOT_FOUND", { resource, id });
   }
 }
 
 export class PermissionDeniedError extends ApplicationError {
-  readonly type = 'permission_denied' as const;
+  readonly type = "permission_denied" as const;
   readonly statusCode = 403;
   constructor(permission: string) {
-    super(`Permission denied: ${permission}`, 'MSG_PERMISSION_DENIED', { permission });
+    super(`Permission denied: ${permission}`, "MSG_PERMISSION_DENIED", {
+      permission,
+    });
   }
 }
 
 export class ConflictError extends ApplicationError {
-  readonly type = 'conflict' as const;
+  readonly type = "conflict" as const;
   readonly statusCode = 409;
   constructor(message: string, details?: ErrorDetails) {
-    super(message, 'MSG_CONFLICT', details);
+    super(message, "MSG_CONFLICT", details);
   }
 }
 
 export class BusinessError extends ApplicationError {
-  readonly type = 'business' as const;
+  readonly type = "business" as const;
   readonly statusCode = 422;
   constructor(message: string, details?: ErrorDetails) {
-    super(message, 'MSG_BUSINESS_ERROR', details);
+    super(message, "MSG_BUSINESS_ERROR", details);
   }
 }
 
 export class DatabaseError extends ApplicationError {
-  readonly type = 'database' as const;
+  readonly type = "database" as const;
   readonly statusCode = 500;
   constructor(message: string, details?: ErrorDetails) {
-    super(message, 'MSG_DATABASE_ERROR', details);
+    super(message, "MSG_DATABASE_ERROR", details);
   }
 }
 
 export class InternalError extends ApplicationError {
-  readonly type = 'internal' as const;
+  readonly type = "internal" as const;
   readonly statusCode = 500;
   constructor(message: string, details?: ErrorDetails) {
-    super(message, 'MSG_INTERNAL_ERROR', details);
+    super(message, "MSG_INTERNAL_ERROR", details);
+  }
+}
+
+/**
+ * ES 不可用且无降级路径（503）。
+ * 仲裁依据：02-architecture-design.md §6.2
+ */
+export class EsUnavailableError extends ApplicationError {
+  readonly type = "internal" as const;
+  readonly statusCode = 503;
+  constructor(message: string, details?: ErrorDetails) {
+    super(message, "MSG_ES_UNAVAILABLE", details);
+  }
+}
+
+/**
+ * Redis 不可用且无降级路径（503）。
+ * 仲裁依据：02-architecture-design.md §6.2
+ */
+export class RedisUnavailableError extends ApplicationError {
+  readonly type = "internal" as const;
+  readonly statusCode = 503;
+  constructor(message: string, details?: ErrorDetails) {
+    super(message, "MSG_REDIS_UNAVAILABLE", details);
+  }
+}
+
+/**
+ * Push Gateway 不可用（503）。
+ * 仲裁依据：02-architecture-design.md §6.2 + coord M4（软失败，仅必要时抛出）
+ */
+export class PushGatewayUnavailableError extends ApplicationError {
+  readonly type = "internal" as const;
+  readonly statusCode = 503;
+  constructor(message: string, details?: ErrorDetails) {
+    super(message, "MSG_PUSH_GATEWAY_UNAVAILABLE", details);
+  }
+}
+
+/**
+ * 通知模板不存在（404）。
+ * 仲裁依据：02-architecture-design.md §6.2
+ */
+export class TemplateNotFoundError extends ApplicationError {
+  readonly type = "not_found" as const;
+  readonly statusCode = 404;
+  constructor(templateCode: string) {
+    super(
+      `Notification template not found: ${templateCode}`,
+      "MSG_TEMPLATE_NOT_FOUND",
+      { templateCode },
+    );
+  }
+}
+
+/**
+ * 模板渲染失败（变量缺失等，422）。
+ * 仲裁依据：02-architecture-design.md §6.2
+ */
+export class TemplateRenderError extends ApplicationError {
+  readonly type = "business" as const;
+  readonly statusCode = 422;
+  constructor(message: string, details?: ErrorDetails) {
+    super(message, "MSG_TEMPLATE_RENDER_ERROR", details);
+  }
+}
+
+/**
+ * 通知频率超限（429）。
+ * 仲裁依据：02-architecture-design.md §6.2（NotificationPreference.frequency_limit 预留）
+ */
+export class RateLimitExceededError extends ApplicationError {
+  readonly type = "business" as const;
+  readonly statusCode = 429;
+  constructor(message: string, details?: ErrorDetails) {
+    super(message, "MSG_RATE_LIMIT_EXCEEDED", details);
   }
 }