基于Cloud Foundry的云计算PaaS平台拓扑展示设计与实现

云计算PaaS（platformasaservice，平台即服务）平台是互联网领域近几年来非常热的技术方向，不仅可以为用户提供开发环境、开发平台和硬件资源，还可以提高硬件资源的利用率，降低业务运营成本。然而，在提供服务的过程中，缺乏一种有效的机制来约束服务提供商的行为。文章为实现云计算PaaS平台下对应用的监测，提出了拓扑管理的概念。应用拓扑可以监测应用与资源的关系，资源拓扑可以监测资源与应用的关系，两者从不同的角度实现对应用的监测。文章采用哈希数组保存拓扑信息，采用消息总线的“发布-订阅”模式传递消息，实现拓扑信息的获取，将结果使用网页进行展示。本系统可以使服务提供商清晰地掌握系统中应用与资源的关系以及资源情况，有效提高资源利用率，因此，系统可以提升服务质量，进而保障用户利益。应用拓扑展示和资源拓扑展示可以及时反映系统中应用与资源的关系，从两种不同的角度展示出来，给云计算提供者管理应用提供了很大的方便。

Design and Implementation of Topology Display in Cloud Computing PaaS based on Cloud Foundry

Cloud computing PaaS （platform as a service） platform draws wide attentions in recent years. Not only does it provide environment and resources for users, it also improves the utilization of hardware resources and reduces business operation costs. However, there is lack of mechanism to constrain the behavior of providers. In order to ifll the gap, the concept of topology management was brought up. In one hand, the application topology can monitor the relationship between applications and resources, in another hand, resource topology can monitor the relationship between resources and applications, both of them can realize monitoring of applications from different angles. We use a hash array to store topology information, and the message bus publish-subscribe model to pass the messages. After that, we can achieve the topology information, and then demonstrate the results in Web pages. To sum up, the PaaS platform driven by Cloud Foundry designed and implemented in this paper runs well. It presents the resource pool information and the relationship between application and resources clearly. Thus, the system can improve the quality of services and protect the interests of users. Application topology display and resource topology display can duly relfect the relationship between resources and application of the system, both of them display from different angles can provides great convenience to the cloud provider to manage application.