Multitier Debugging of Web Applications.

Debugging Web applications is difficult because of their distributed nature and because the server-side and the client-side of the application are generally treated separately. The multitier approach, which reunifies the two ends of the application inside a unique execution environment, helps the debugging process because it lets the debugger access more runtime informations. We have built a multitier debugger for an extension of JavaScript. Its advantage over most debuggers for the Web is that it reports the full stack trace containing all the server-side and client-side frames that have conducted to an error. Errors are reported on their actual position on the source code, wherever they occur on the server or on the client. This paper presents this debugger and sketches its implementation.