I'm totally new to this site monitoring thing, so please bear with me.
I'm looking for a good monitoring service for my website. What I'm trying do is make sure the site is running and working not just running (ie. responsive and working, not just responsive). For example, the database could be down, so the site is responsive but not working, this means with every request you will get an error page instead of the page you want. How do you normally handle this?
In my app, I have something like a fatal error mode, if something goes wrong that the app can't recover from (like when the database is down for example), then the app is set to fatal error mode and will always transfer to a page that says something like 'We're having some technical problem and will be back online soon' (this is done to avoid returning errors with every request, which is not pleasant for the user experience, and also to avoid logging tons of errors which are all basically the same).
I'm thinking about writing a webservice that the monitoring service should call. The webservice should return a boolean value, so, if it returns true then the site is working but if it returns false, then this means that something is wrong. Is it possible to find a monitoring service that can check the value returned from the webservice and notify me if it's not the expected value?
Sorry for the long question and thanks for any suggestions