Abstract: In order to satisfy tenants’ customization requirements, cloud system should adapt to constantly variable requirements and variety in business area. So, a novel method constructing cloud system in flexible SaaS（Software as a Service） patterns is proposed. Following the guidance of flexible thought, the method introduces a series of steps containing service division, constructing service extended structure and so on to help developer analysis and design the whole structure of services and its extensible functions, then, by means of software development based on plug-in and dynamically assembling framework Equinox, services and plug-ins are dynamically assembled into complete services for tenants. Finally, to confirm the maneuverability and effectiveness of this flexible method, it is introduced into a communication project.

Key words: Software as a Service（SaaS）, flexible thought, service division, dynamically assembling framework

摘要： 为了满足租户的业务定制需求，云服务系统必须对租户不断变更的需求及业务领域内流程变化具有一定的适应性，为此，提出一种在柔性SaaS模式下构建云服务系统的方法。该方法以柔性思想为指导，通过服务规划，构建服务扩展结构等一系列步骤，分析设计整体服务及其扩展功能结构；经由基于插件的软件开发方法和动态组装框架Equinox，将服务及插件动态装配为“完整服务”供租户使用。把该柔性方法引入到一个物流项目中，以证实其可操作性及有效性。

关键词: 软件即服务, 柔性思想, 服务规划, 动态组装框架