我过去一直是REST的忠实粉丝，它在纸上比RPC有很多优势。你可以给客户端提供不同的内容类型、缓存、HTTP状态代码的重用，你可以通过API引导客户端，如果API不是大部分都是自解释的，你可以在API中嵌入文档。

But my experience has been that in practice this doesn't hold up and instead you do a lot of unnecessary work to get everything right. Also the HTTP status codes often don't map to your domain logic exactly and using them in your context often feels a bit forced. But the worst thing about REST in my opinion is that you spend a lot of time to design your resources and the interactions they allow. And whenever you do some major additions to your API you hope you find a good solution to add the new functionality and you didn't design yourself into a corner already.

This often feels like a waste of time to me because most of the time I already have a perfectly fine and obvious idea about how to model an API as a set of remote procedure calls. And if I have gone through all this effort to model my problem inside the constraints of REST the next problem is how to call it from the client? Our programs are based on calling procedures so building a good RPC client library is easy, building a good REST client library not so much and in most cases you will just map back from your REST API on the server to a set of procedures in your client library.

正因为如此，今天对我来说，RPC感觉更简单、更自然。不过，我真正怀念的是一个一致的框架，它可以很容易地编写自描述和可互操作的RPC服务。因此，我创建了自己的项目，尝试新的方法使RPC对我自己更容易，也许其他人也会发现它有用:https://github.com/aheck/reflectrpc

我使用vdata为RPC协议: http://vdata.dekuan.org/

1、PHP和JavaScript都没问题。 2、跨源资源共享(CORS)呼叫仍然正常。

我认为，一如既往，这取决于……

REST具有广泛的公众支持的巨大优势，这意味着有大量的工具和书籍。如果你需要制作一个API，让来自不同组织的大量消费者使用，那么只有一个原因:它是受欢迎的。作为一种协议，它当然是完全失败的，因为有太多完全不同的方法来将命令映射到URL/动词/响应。

因此，当你编写一个需要与后端对话的单页web应用程序时，我认为REST太复杂了。在这种情况下，你不必担心长期的兼容性，因为应用程序和API可以一起发展。

I once started with REST for a single page web app but the fine grained commands between the web app and the server quickly drove me crazy. Should I encode it as a path parameter? In the body? A query parameter? A header? After the URL/Verb/Response design I then had to code this mess in Javascript, the decoder in Java and then call the actual method. Although there are lots of tools for it, it is really tricky to not get any HTTP semantics in your domain code, which is really bad practice. (Cohesion)

尝试为中等复杂的站点制作一个Swagger/OpenAPI文件，并将其与该文件中描述远程过程的单个Java接口进行比较。复杂性的增长是惊人的。

因此，对于单页web应用程序，我从REST切换到JSON-RPC。aI开发了一个小型库，在服务器上编码Java接口，并将其传送到浏览器。在浏览器中，这为为每个函数返回承诺的应用程序代码创建了一个代理。

同样，REST也有它的地位，因为它很有名，因此得到了很好的支持。认识到底层的无状态资源哲学和层次模型也很重要。然而，这些原则同样可以在RPC模型中使用。JSON RPC工作于HTTP之上，因此它在这方面具有与REST相同的优势。不同之处在于，当您不可避免地遇到这些不能很好地映射到这些原则的函数时，您不必被迫做大量不必要的工作。

在我看来，关键在于行动vs资源导向。REST是面向资源的，非常适合CRUD操作，并且由于其已知的语义为第一个用户提供了一些可预测性，但是当从方法或过程实现时，将迫使您提供对以资源为中心的世界的人工转换。另一方面，RPC非常适合面向操作的api，在这种api中，您公开的是服务，而不是可用于RPC的资源集。

毫无疑问REST更受欢迎，如果你想将API公开给第三方，这无疑会增加一些好处。

如果不是(例如在SPA中创建AJAX前端)，我的选择是RPC。特别是JSON- rpc，结合JSON Schema作为描述语言，并根据用例通过HTTP或Websockets传输。

JSON-RPC是一个简单而优雅的规范，它定义了用于同步或异步RPC的请求和响应JSON有效负载。

JSON Schema是一份规范草案，定义了一种基于JSON的格式，旨在描述JSON数据。通过使用JSON Schema描述您的服务输入和输出消息，您可以在消息结构中拥有任意的复杂性，而不会影响可用性，并且可以自动化服务集成。

传输协议(HTTP vs websockets)的选择取决于不同的因素，最重要的是你是否需要HTTP特性(缓存、重新验证、安全性、幂等性、内容类型、多部分等等)，或者你的应用程序是否需要在高频率下交换消息。

到目前为止，这主要是我个人对这个问题的看法，但是现在有一些东西可以真正帮助那些阅读这些行的Java开发人员，我在过去的一年里一直在工作的框架，诞生于你现在想知道的同一个问题:

http://rpc.brutusin.org

你可以在这里看到一个现场演示，展示了用于功能测试的内置存储库浏览器(感谢JSON Schema)和一系列示例服务:

http://demo.rpc.brutusin.org

希望对伴侣有帮助!

Nacho

RPC的基本问题是耦合。RPC客户端以多种方式与服务实现紧密耦合，在不破坏客户端的情况下更改服务实现变得非常困难:

客户需要知道过程名称; 程序参数顺序，类型和计数事项。在不破坏客户端实现的情况下，在服务器端改变过程签名(参数的数量、参数的顺序、参数类型等)并不是那么容易的; RPC样式只公开过程端点+过程参数。客户不可能决定下一步该做什么。

另一方面，在REST风格中，通过在表示(HTTP报头+表示)中包含控制信息来引导客户端是非常容易的。例如:

It's possible (and actually mandatory) to embed links annotated with link relation types which convey meanings of these URIs; Client implementations do not need to depend on particular procedure names and arguments. Instead, clients depend on message formats. This creates possibility to use already implemented libraries for particular media formats (e.g. Atom, HTML, Collection+JSON, HAL etc...) It's possible to easily change URIs without breaking clients as far as they only depend on registered (or domain specific) link relations; It's possible to embed form-like structures in representations, giving clients the possibility to expose these descriptions as UI capabilities if the end user is human; Support for caching is additional advantage; Standardised status codes;

在REST方面还有更多的区别和优势。

我过去一直是REST的忠实粉丝，它在纸上比RPC有很多优势。你可以给客户端提供不同的内容类型、缓存、HTTP状态代码的重用，你可以通过API引导客户端，如果API不是大部分都是自解释的，你可以在API中嵌入文档。

But my experience has been that in practice this doesn't hold up and instead you do a lot of unnecessary work to get everything right. Also the HTTP status codes often don't map to your domain logic exactly and using them in your context often feels a bit forced. But the worst thing about REST in my opinion is that you spend a lot of time to design your resources and the interactions they allow. And whenever you do some major additions to your API you hope you find a good solution to add the new functionality and you didn't design yourself into a corner already.

This often feels like a waste of time to me because most of the time I already have a perfectly fine and obvious idea about how to model an API as a set of remote procedure calls. And if I have gone through all this effort to model my problem inside the constraints of REST the next problem is how to call it from the client? Our programs are based on calling procedures so building a good RPC client library is easy, building a good REST client library not so much and in most cases you will just map back from your REST API on the server to a set of procedures in your client library.

正因为如此，今天对我来说，RPC感觉更简单、更自然。不过，我真正怀念的是一个一致的框架，它可以很容易地编写自描述和可互操作的RPC服务。因此，我创建了自己的项目，尝试新的方法使RPC对我自己更容易，也许其他人也会发现它有用:https://github.com/aheck/reflectrpc