Ruby how to format nested hash - ruby-on-rails

Question

I have two queries I am running and iterating over both and my final hash is seen below. But, I want to have format on how the data is being stored in the hash that I'm creating or format it after I'm done creating it. But I am not sure how to achieve the desired format where the names fall under the same id as show below
desired format of example data:
[
{
id: 1,
accepted: false,
trans: 10234
names: [
{ name: "Joe", amount: "$1,698.00" },
{ name: "Smith", amount: "$674.24" },
]
},
{
id: 2,
accepted: true,
trans: 10234,
names: [
{ name: "Joe", amount: "$1,698.00" },
{ name: "Smith", amount: "$674.24" },
]
}
]
current format I have
[
{
:id => 1,
:accepted => false,
:trans => 8,
:name => "Smith",
:amount => 36.0
},
{
:id => 1,
:amount => false,
:trans => 8,
:name => "Joe",
:amount => 6.0
},
{
:id => 3,
:accepted => false,
:trans => 8,
:name => "Tom",
:amount => 34.0
},
{
:id => 3,
:accepted => false,
:trans=> 8,
:name => "Martha",
:amount => 4.0
}
],
[
{
:id => 2,
:accepted => true,
:trans => 7,
:name => "Bob",
:amount => 35.0
},
{
:id => 2,
:accepted => true,
:trans => 7,
:name => "John",
:amount => 5.0
}
]
logic for creating hash
imports = ListImports.limit(20).order(created_at: :DESC)
groups = imports.map{|import| ListImportGroup.where(list_import_id: import.id)}
pub_hash_true = []
pub_hash_false = []
hash = []
imports.map do |import|
hash << {
id: import.id,
trans: import.trans,
accepted: import.amount
}
end
hash.each do |import|
groups.flatten.each do |group|
accepted = import[:accepted]
num_transactions = import[:trans]
if accepted == false
pub_hash_false << {id: import[:id], accepted: accepted, trans: num_transactions, name: group.name, amount: group.amount}
else
pub_hash_true << {id: import[:id], accepted: accepted, trans: num_transactions, name: group.name, amount: group.amount}
end
end
end

Answer 1

# Note: You didn't specify what is the association between `ListImport` and `ListImportGroup`.
# However, I'm fairly sure you could be fetching this data via a JOIN query like below,
# rather than making up to 20 additional database calls to fetch the associated records.
imports = ListImports.limit(20).order(created_at: :DESC).includes(:list_import_group)
result = imports.map do |import|
{
id: import.id,
trans: import.trans,
accepted: import.amount,
names: import.list_import_groups.pluck(:name, :amount)
}
end
And if you do actually need to filter for imports where accepted is true or false, you could do something like this instead of building separate arrays manually:
accepted_imports = result.select { |import| import[:accepted] }
# and
rejected_imports = result.reject { |import| import[:accepted] }
# or even:
accepted_imports, rejected_imports = result.partition { |import| import[:accepted] }

Answer 2

You didn't specify the exact correspondence between the desired and current formats.
But I assume
For the entries with the same id, the values of accepted and trans are identical.
the desired amount for Joe in the current format is identical in the corresponding amount in the desired amount. (In your example, the former is 6.0 whereas the latter is "$1,698.00", which does not make sense.)
Then, the following would do the conversion. The array ahout is in the desired format.
# Let us assume "a1" is the original array in the "current format"
hout = {}
a1.flatten.map{|h|
h.slice(*(%i(id trans name amount accepted))).values
}.each{ |a|
hout[a[0]] = {id: a[0], accepted: a[4], trans: a[1], names: []} if !hout.key? a[0]
hout[a[0]][:names].push(
{name: a[2], amount: "$"+helper.number_with_precision(a[3], precision: 2, delimiter: ',')}
)
}
ahout = hout.values
You may want to sort ahout, if you like.
Note that I am assuming you are using Rails 5+. Otherwise, the method helper may not work. In that case, you can use sprintf or whatever formatting method.