Source maps are available on most environments we support.
To enable sourcemaps in the Sprockets processor you need to turn on the relative flag:
Opal::Config.source_map_enabled = true # default
The source maps only work with Sprockets in debug mode - this is a limitation of Sprockets.
Rails has debug mode already enabled in development environment with the following line from
# Debug mode disables concatenation and preprocessing of assets. # This option may cause significant delays in view rendering with a large # number of complex assets. config.assets.debug = true
opal-rails also enables sourcemaps in development so with the standard setup you ready to go.
You can add
Opal::Server as in the official example: sinatra/config.ru.
Opal::Server (which is based on Sprockets) implements sourcemaps and can be used alone or with
Rack::Cascade in conjunction with other apps.
Opal::SimpleServer (which isn't based on Sprockets) implements sourcemaps properly.
Opal::Builder is a bit lower level and doesn't support source maps by itself. It requires you to call in a specific method to generate them yourself.