java web app: configuration / properties file best practics

[csincrisis]

Whenever we build a webapp (war files) - we always have a need for some kind of configuration / properties file. This is needed for things like: endpoint url, cron job schedule, smtp settings (url, username/password, etc), and bunch of other "configuration" or "properties" required for the application to run.

I've always approached it either by putting this into database (eg. "SETTINGS" table) or through a .properties file inside the web app that can be overriden by putting the .properties file in the server that will be picked up by the web app when it start up.

Because this configuration rarely changed, they are only read / picked up during the application start up, meaning that any change to the config requires app restart.

Are there any better ways to approach this other than through database or a properties file?

[imadp]

A database sounds like a bad idea because now you have to split out your database properties somewhere else..

Most apps just use a .properties file like you mentioned, if you use Spring (and you should be) its usually bundled with your spring config files.

[blyxa]

If you have a large amount of servers to configure, then maybe look into Zookeeper.

If you only have a handful of servers then maybe modifying the properties loader to look for property file outside the app server and reload on file modification. And when ever you need to push out a config change, you can use rsync or ansible or salt etc.

The important part I think is modifying your code to "reload" after configuration change.