Migrate url 404 not found page after depvelop to new system with nop commerce source

Are there any way no touch to nop source code and create widget plugin to mapping old url to new url
I write one widget but I must to modify PageNotFound in CommonController and global.ascx

eg: my old link
http://badpaybad.info/blog-121/complex-redis-usage-with-c-the-chickchat-servcies
I will redirect to new link
http://badpaybad.info/redis-usage-with-c

This function will help your site keep google indexed with old link, the google bot will not marked as 404 page