disable unit caching specifically in rake tasks by davidsbailey · Pull Request #71582

disable unit caching specifically in rake tasks by davidsbailey · Pull Request #71582 · code-dot-org/code-dot-org

Follow-up from:

#71467 attempted to limit unit caching to running (puma) web servers, but this exposed an error in our existing logic in CDO.running_web_application? leading to performance issues in production.

A fix has been opened for the logic in CDO.running_web_application?, but I don't want this work to take a dependency on that work, so this PR offers a more scoped fix of just disabling caching within rake tasks.

Testing story

all rake tasks for building and testing have already been validated to some extent as part of shipping only cache units and courses within running web application #71467 -- we didn't notice any issues with that PR until we hit peak traffic the following morning.
manually verified this has the intended effect locally:

[10:42:13] Dave-M4:~/src/cdo/dashboard (skip-unit-cache-in-rake *)$ git diff
diff --git a/dashboard/config/environments/development.rb b/dashboard/config/environments/development.rb
-  config.cache_classes = false
-  config.cache_store = :null_store
+  config.cache_classes = true
diff --git a/dashboard/lib/services/script_seed.rb b/dashboard/lib/services/script_seed.rb
         seed_context.script = import_script(script_data, md5: md5)
+        puts "Unit.should_cache? #{Unit.should_cache?}"

[10:35:25] Dave-M4:~/src/cdo/dashboard (staging *)$ bundle exec rake seed:single_script SCRIPT_NAME=allthethings
Unit.should_cache? true
Finished seed:single_script (1 second)

[10:42:01] Dave-M4:~/src/cdo/dashboard (skip-unit-cache-in-rake *)$ bundle exec rake seed:single_script SCRIPT_NAME=allthethings
Unit.should_cache? false
Finished seed:single_script (1 second)