如何在不删除/取消部署旧应用程序的情况下在tomcat中重新部署war文件？

Question

I already have a working Tomcat Server with Web Manager where I can deploy my WAR file.

The WAR file contains my web application and this web application has a feature where user can upload images into one of it's folder.

The problem is when I need to update the web application using a new WAR file.

When I upload it through Tomcat manager. It says WAR file already exist. I have to UNDEPLOY it first before I can upload the updated WAR.

I don't want to do this UNDEPLOY process because it will delete the application along with all the images that user already uploaded.

So, how can I update my web application without deleting those uploaded files? Or maybe I was using the wrong approach with my application?

Answer 1

Since I need a quick fix. Here is what I did to make it work:

1. Create a temporary folder anywhere on the server lets say "/var/tmp/war_images". This will be used to temporarily store uploaded images when deploying a new war
2. Create a folder to put new WAR file. lets say "/var/tmp/war"
3. Create a shell script that do these things:
   • Copy all images from folder where user upload their images to the temp folder above
   • Delete application folder in tomcat
   • Delete WAR file in tomcat
   • Copy new WAR file from point 2 to tomcat8 folder
   • Restart tomcat (to trigger the deployment)
   • Copy back all images from point no.1 back to app folder newly created by the deployment process

So when I want to deploy a new WAR. I put the new WAR file on step no.2 and then execute the shell script.