Is there a way of caching the output of docker-php-ext-install in BitBucket Pipelines?

Question

We've just started using Pipelines for some of our PHP projects, and a major amount of the pipeline time is going on running docker-php-ext-install to install the required PHP extensions. I know I can define my own docker image that includes these extensions but I'd rather use the built in caching on Pipelines if possible. Is there any way to use Pipelines caching to save the results of docker-php-ext-install?

Grant Lucas · Answer

Do you have any more information on what might be needed for this. At this time I've tried the following but it doesn't seem to be working

definitions:
 caches:
    php-ext-source: /usr/src/php/ext
    php-ext: /usr/local/lib/php/extensions

And then these cache definitions were added to my pipelines. Am I correct in that I'd just need to add locations where stuff is installed to add a new cache?

Grant Lucas · Answer

Ah, looks like we're in the same boat then :)  I'll be sure to update here should I figure anything out.

alnorth · Answer

No, I didn't. I'd still be interested if anyone else works it out. However, I think the proper solution is just to bite the bullet and define your own custom Docker image. I'm not that familiar with Docker so I haven't taken the time to do it yet.