SHF: Small: Higher-order Contracts for Distributed Applications

分布式应用程序(如Web应用程序和基于云的应用程序，其中多台计算机协作运行应用程序)正变得越来越普遍。考虑到这些分布式应用程序处理的商业活动和信息的数量，这些应用程序正确、可靠和高效是很重要的。然而，许多传统的程序员工具和技术不能用于分布式应用程序，这使得程序员很难编写和调试分布式应用程序。这项研究探索了软件合同在分布式应用程序中的使用。软件合同是可在运行时(即，当软件执行时)检查的软件组件的规范。通过开发将软件合同合并到分布式应用程序中的技术和工具，该研究有可能使程序员更容易编写正确、可靠和高效的分布式应用程序。具体地说，该研究探索了更高顺序的合同在分布式应用程序中的使用。高阶合同是指一类函数或对象等高阶数值的合同。高阶契约非常适合分布式应用程序，因为分布式应用程序中的组件通常是高阶的，并且高阶契约有助于对组件的动态组合进行推理(这在分布式环境中很常见，例如Web应用程序)。更高顺序合同的潜在好处包括：(A)组件功能行为的声明性规范；(B)规范的运行时强制执行；以及(C)错误组件的正确识别。这项研究的重点是行为契约的有效执行，在存在不可信任的分布式组件的情况下正确执行契约，以及非功能行为的规范和执行。

Distributed applications (such as web applications and cloud-based applications, where multiple computers cooperate to run the application) are becoming increasingly common. Given the amount of commercial activity and information handled by these distributed applications, it is important that these applications are correct, reliable, and efficient. However, many traditional tools and techniques for programmers cannot be used for distributed applications, making it difficult for programmers to write and debug distributed applications. This research explores the use of software contracts for distributed applications. Software contracts are specifications for software components that can be checked at run time (i.e., when the software executes). By developing techniques and tools to incorporate software contracts into distributed applications, this research has the potential to make it easier for programmers to write distributed applications that are correct, reliable, and efficient.Specifically, this research explores the use of higher-order contracts for distributed applications. Higher-order contracts are contracts for higher-order values such as first-class functions or objects. Higher-order contracts are a good fit for distributed applications as components in distributed applications are often higher-order, and higher-order contracts facilitate reasoning about dynamic composition of components (which is common in distributed settings such as web applications). Potential benefits of higher-order contracts include: (a) declarative specification of the functional behavior of components; (b) run-time enforcement of specifications; and (c) correct identification of faulty components. This research focuses on the efficient enforcement of behavioral contracts, the correct enforcement of contracts in the presence of untrustworthy distributed components, and the specification and enforcement of non-functional behaviors.