Selecting items from a hash based on sub-hash values - ruby

Question

I have the following JSON output from an API:
{
"Objects": [
{
"FieldValues": [
{
"Field": {
"Name": "Nuix Field"
},
"Value": "Primary Date"
},
{
"Field": {
"Name": "Field Type"
},
"Value": {
"Name": "Nuix"
}
},
{
"Field": {
"Name": "Field Category"
},
"Value": {
"Name": "Generic"
}
}
]
}
]
}
I want to be able to select all Objects where "Field" has a "Name" of "Field Type" and it's "Value" has a "Name" of "Nuix".
This is my attempt, but I feel like there is a better way to do it?
json = JSON.parse(response)
results = []
json["Objects"].each do |obj|
obj["FieldValues"].each do |fv|
if fv["Field"]["Name"] == "Field Type" && fv["Value"]["Name"] == "Nuix"
results << obj
end
end
end

Answer 1

One of the options is not to loop all FieldValues but only until expected one is found with the any? method.
Then you can simplify code with select method, which will create new array with only "satisfied" objects.
objects_with_required_fields = json.fetch("Objects", []).select do |obj|
obj.fetch("FieldValues", []).any? do |fv|
name = fv.dig("Field", "Name")
value = fv["Value"]
name == "Field Type" && value.is_a?(Hash) && value["Name"] == "Nuix"
end
end

Answer 2

Here's a more minimal Ruby solution:
json = JSON.parse(response, symbolize_names: true)
target = [ 'Field Type', 'Value' ]
# For each of the entries in Objects...
results = json[:Objects].flat_map do |obj|
# ...filter out those that...
obj[:FieldValues].select do |fv|
# ...match the target criteria.
[ fv.dig(:Field, :Name), fv[:Value] ] == target
end
end
Where that uses symbolized keys and just filters through an array of arrays looking for matching entries, then returns those in one (flat) array.