场景驱动且自底向上的单体系统微服务拆分方法

作为云原生应用的一种典型形态，微服务架构已经在各种企业应用系统中被广泛使用.在企业实践中，许多微服务都是在单体架构的遗留系统基础上通过微服务拆分和改造形成的，其中的拆分决策（特别是数据库拆分）对于微服务系统的质量有着很大的影响.目前，单体系统的微服务拆分决策主要依赖于人的主观经验，整个过程成本高、耗时长、结果不确定性很高.针对这一问题，提出一种场景驱动、自底向上的单体系统微服务拆分方法.该方法以场景驱动的方式，通过动态分析获取单体遗留系统运行时的方法调用和数据库操作信息，然后基于数据表之间的关联分析生成数据库拆分方案，接着再自底向上进行搜索，产生相应的代码模块拆分方案.基于这种方法，实现了一个原型工具MSDecomposer，将拆分过程可视化，并支持多种维度的反馈调整策略.基于多个开源软件系统进行了案例研究，研究结果表明，该方法能够显著加快微服务拆分决策的速度，减轻开发人员的决策负担，得到的拆分结果是合理的.

Scenario-driven and Bottom-up Microservice Decomposition Method for Monolithic Systems

As a typical form of cloud-native application, microservice architecture has been widely used in various enterprise applications. In enterprise practice, many microservices are formed by decomposing and transforming the legacy system of monolithic architecture. The decomposition decision, especially database decomposition, has a great impact on the quality of the microservice system. At present, the microservice decomposition decision mainly depends on the human subjective experience. The whole process is costly, time-consuming, and uncertain. To solve this problem, this study proposes a scenario-driven, bottom-up microservice decomposition method for monolithic system. This method uses scenario-driven method to obtain the method call and database operation information of monolithic system by dynamic analysis, and to generate database decomposition scheme based on analyzing the association among data tables, and then it searches from the bottom up to generate the corresponding code module decomposition scheme. Based on this method, this study implements a prototype tool MSDecomposer, which visualizes the decomposing process and supports feedback adjustment strategies of multiple dimensions. This study conducts case studies based on several open-source software systems, and the results show that the method proposed in this study can significantly speed up the decision-making of microservice decomposition, reduce the decision-making burden of developers and the final result is reasonable.