Downstream dependency listing or forced update

[xpcros]

Hi guys,

Just wondering if anyone has a solution for forcing an update of a downstream dependency.

Currently I am having an issue in the office whereby we deploy multiple stacks. The first sceptre template creates a secret with a random generated value, the second template creates a static EC2 database host and uses this generated value when initialising the host to set a SQL database 'sa' password. These are not nested, but the 2nd stack lists the 1st as a dependency. A 3rd template creates a web application that uses this password but it retrieves it each time it is needed.

So;
1st template 'secrets' - creates password
2nd template 'database' - uses password to set up database in userdata/init using bash script.
3rd template 'web' - grabs password every time it is needed to be used to talk to the database

This all worked well until I updated the 1st template to include some 'excluded characters' from the generated password.

After this update I ran Sceptre and;

• 1st template updated secret with the newly generated password.
• 2nd template did not see any change - so the static database did not terminate / restart and start to use the new value.
• 3rd stack web servers picked up new password value because it does this on the fly

Naturally, now the web application could not talk to the database because they had different passwords in use.

So my question is whether there is some functionality in Sceptre that would allow you to either force some update of a downstream template, or at the very least list them out so I could either script these to be recreated or reported on?

I can see upstream dependencies by running;

sceptre list resources database

Many thanks