在tsyringe中键入Resolution

Question

我最近开始使用tsyringe，遇到了如何解决依赖关系的问题。一个可重复的场景解释如下：

class Client {
exec(svcNum: number) {
console.log("Executing ", svcNum);
}
}
@injectable()
class Service1 {
private readonly num = 1;
constructor(private client: Client) {}
serve() {
this.client.exec(this.num);
}
}
@injectable()
class Service2 {
private readonly num = 2;
constructor(private client: Client) {}
serve() {
this.client.exec(this.num);
}
}

我有一个Client类，它是Service1和Service2使用的依赖项。这些问题可以像这样简单地解决：

const resolvedSvc1 = container.resolve(Service1);
const resolvedSvc2 = container.resolve(Service2);

现在我需要的是这样的东西：

container.register(Service1, { useClass: Service1 });
container.register(Service2, { useClass: Service2 });
const services = [ Service1, Service2 ]; // typeof Service1 | Service 2
services.forEach((svc) => {
//container.register((svc as any).name, { useClass: svc });
if (container.isRegistered((svc as any).name)) {
console.log("Found registered service ", svc.name);
}
const resolved = container.resolve<typeof svc>(svc.name);
(resolved as any).serve();
});

这不起作用，TypeScript在我运行代码时抱怨Error: Attempted to resolve unregistered dependency token: "Service1"；此外，console.log在if块中不打印任何内容。我发现svc有一个并集类型Service1 | Service2，这可能是问题的原因。有什么方法可以在运行时以这种方式动态解析服务的依赖关系吗？将svc缩小到适当的类型(即，我想Service1或Service2都可以(。

Answer 1

您正在使用class注册服务，但随后尝试通过name:检索它们

container.register(Service1, { useClass: Service1 });
//                 ^^^^^^^^ ✅ registering the class here

const resolved = container.resolve<typeof svc>(svc.name);
//                ❌ trying to resolve by name ^^^^^^^^

有两种解决方案：

// Option 1: register by class and resolve by class
container.register(Service1, { useClass: Service1 });
//                 ^^^^^^^^ ✅ register by class
const resolved = container.resolve<typeof svc>(svc);
//                         ✅ resolve by class ^^^

// Option 2: register using the class name and resolve by class or class name
container.register(Service1.name, { useClass: Service1 });
//                 ^^^^^^^^^^^^^ ✅ register by class name
// can resolve by class
const resolved = container.resolve<typeof svc>(svc);
//                         ✅ resolve by class ^^^
// can resolve by class name
const resolved = container.resolve<typeof svc>(svc.name);
//                        ✅ resolve by class name ^^^^