app/controllers/canvas_lti_controller.rb
# If no query parameters are present, returns a URL corresponding to the app server.
# If 'app_host' is specified, then the URL points to the app_host server, which is assumed
# to be a shared server behind https.
# Example: https://calcentral.berkeley.edu/canvas/lti_roster_photos.xml?app_host=sometestsystem.berkeley.edu
If no query parameters are present, returns a URL corresponding to the app server.
If 'app_host' is specified, then the URL points to the app_host server, which is assumed
to be a shared server behind https.
If no query parameters are present returns a URL corresponding to the app server . If ' app_host ' is specified then the URL points to the app_host server which is assumed to be a shared server behind https .
def launch_url(app_name)
    if (app_host = params["app_host"])
      launch_url_for_host_and_code("https://#{app_host}", app_name)
    else
      url_for(only_path: false, action: 'embedded', url: app_name)
    end
  end
def launch_url ( app_name ) if ( app_host = params [ "app_host" ] ) launch_url_for_host_and_code ( "https://#{app_host}" , app_name ) else url_for ( only_path : false , action : 'embedded' , url : app_name ) end end
If no query parameters are present, returns a URL corresponding to the app server.
If no query parameters are present returns a URL corresponding to the app server .
app_name