目前雲端運算技術上的優勢,使得將現有的Web應用程式遷移到雲端運算平台已成為一種趨勢。然而,在考量雲端服務的需求下(多租戶管理、租戶間資料隔離、租戶間差異管理)進行遷移時,若採用傳統的物件導向分析方法,會修改到很多既有模組,且難以驗證系統原有的需求及雲端服務的需求是否能正確地在雲端運算平台上運行,導致系統不易開發和維護。因此,本論文提供一套將Web應用程式遷移至雲端之方法,協助開發團隊將現有的Web應用程式有步驟地遷移至雲端平台,並用AOP技術將新加入的程式碼縫入系統中,使得團隊在維護同一套程式碼的情況下,讓Web應用程式的現行版本與遷移後的雲端版本之功能保持同步。本論文以一個Web應用程式-ezScrum作為案例探討。
With many advantages of cloud computing, it has become a trend to migrate web applications to the cloud platform. To meet the requirements of cloud service (multi-tenancy, tenant isolation, tenant variation management), many modules of system design need to be modified if a traditional OOAD method is adopted. Further, it is also hard to verify if both the original requirements and the additional cloud service requirements work correctly. This thesis proposes a method for migrating web applications to the cloud in systematic way. With the use of AOP technology, code of implementing cloud service requirements can be cleanly added to the existing code. As a result, the development team is able to maintain a common system code base for producing both the web and the multi-tenant cloud versions. The proposed method is demonstrated by making ezScrum both a web application and a multi-tenant cloud service.