Ruby 如何格式化嵌套哈希

Question

我有两个查询我正在运行并迭代这两个查询，我的最终哈希如下所示。 但是，我想对数据如何存储在我创建的哈希中进行格式化，或者在创建完成后对其进行格式化。 但我不确定如何实现所需的格式，其中names与下面显示的id相同

示例数据的所需格式：

[
    {
        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" },
        ]
    }
]

我的当前格式

[
    {
               :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
    }
]

创建哈希的逻辑

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

如果您确实需要过滤accepted为true或false导入，您可以执行以下操作，而不是手动构建单独的数组：

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

您没有指定所需格式和当前格式之间的确切对应关系。 但我假设

• 对于具有相同id的条目， accepted和trans的值是相同的。
• 乔在当前格式所需的量在以期望的量相应的量相同。 （在您的示例中，前者是6.0而后者是"$1,698.00" ，这是没有意义的。）

然后，以下将进行转换。 数组ahout所需的格式。

 # 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

如果您愿意，您可能想对ahout进行排序。

请注意，我假设您使用的是 Rails 5+。 否则，方法helper可能无法工作。 在这种情况下，您可以使用sprintf或任何格式化方法。