Restore manifest is failing on rollback on multiple hosts

[mckomo]

I have an issue during rollback on multiple host setup with restoring assets manifest. Currently restoring manifest works like this. It checks manifest name in assets_manifest_backup dir on one host and then uses this name to check again (assets.rake#L93) on each host if this manifest exists before copying archived manifest to public/assets dir.
This strategy fails when each host have different manifest (I know it's very unusual) and throws Capistrano::FileNotFound error (assets.rake#L98).

I propose we should detect manifest name per host.

System configuration

Ruby 2.4.1
capistrano (3.8.2)
capistrano-bundler (1.2.0)
capistrano-passenger (0.2.0)
capistrano-rails (1.2.3)
rails (4.2.9)
rails-deprecated_sanitizer (1.0.3)
rails-dom-testing (1.0.8)
rails-html-sanitizer (1.0.3)
rake (12.0.0)
rspec-rails (3.6.0)
rvm1-capistrano3 (1.4.0)
sass-rails (5.0.6)
sequel-rails (0.9.17)
sprockets-rails (3.2.0)

[mattbrictson]

Hi! Thanks for the bug report. Is this still a problem for you?

I am looking at the source code you referenced (see below), and it seems to me that manifest detection happens inside the on block, and therefore it is executed per host. I am not seeing the place in the code where the name detected on one host is applied to other hosts. Can you clarify?

rails/lib/capistrano/tasks/assets.rake

Lines 88 to 102 in 0a65584

	task :restore_manifest do
	on release_roles(fetch(:assets_roles)) do
	within release_path do
	target = detect_manifest_path
	source = release_path.join('assets_manifest_backup', File.basename(target))
	if test "[[ -f #{source} && -f #{target} ]]"
	execute :cp, source, target
	else
	msg = 'Rails assets manifest file (or backup file) not found.'
	warn msg
	fail Capistrano::FileNotFound, msg
	end
	end
	end
	end

[AndreVolpi]

Probably this problem is similar to the one I just had, due to detect_manifest_path listing all manifests separated by space, if you have more than one (like we did here by mistake) the target variable becomes something like: path1 path2 and it breaks the test function (because it becomes [[ -f path1 && -f path2 path3]], imo the return from detect_manifest_path should be different in case there is more than one.