I have had a to load a list of valid country and currency mappings for sharesight. It proved difficult to find a current correct list with the mapping between currency and country on the internet that is easily extractable.
wikipedia has a good source of current and obsolete codes – currency codes ISO 4217, country codes ISO 3166.
Here is what we came up with. If anyone knows of a reliable up to date source then please comment.
And to load into your rails app