This code:
@countries.map { |l| [l.country_name, l.latitude, l.longitude, l.capital] }
returns
[["country_name_1", latitude, longitude, capital],["country_name_2", latitude, longitude, capital],...]
But I need to convert to JSON; something like this:
{
"country_name_1" : [latitude, longitude, "capital"],
"country_name_2" : [latitude, longitude, "capital"],
.
.
.
}
This should work:
Hash[@countries.map { |l| [l.country_name, [l.latitude, l.longitude, l.capital]] }]
Rails also provides index_by:
@countries.index_by(&:country_name)
# => {
# "country_name_1" => #<Country latitude:..., longitude:...>,
# "country_name_2" => #<Country latitude:..., longitude:...>,
# }
Objects might be more convenient than hashes.
Rails has built-in support for JSON: http://guides.rubyonrails.org/layouts_and_rendering.html#rendering-json
You can also call to_json manually:
hash = Hash[@countries.map { |l| [l.country_name, [l.latitude, l.longitude, l.capital]] }]
hash.to_json
Or use the JSON Builder gem.
