Question

I’m attempting to convert MySQL timestamps in an ActiveRecord object to another timestamp format. My method takes an array of ActiveRecord records and returns an array of hashes with the timestamped fields with the formatted timestamp:

def convert_mysql_timestamps(records)
    ary = []
    hash = {}
    records.each_with_index do |record, i|
      record.attributes.each do |field, value|
        if time_columns.include?(field) and value then
          hash[field] = value.strftime("%Y-%m-%dT%H:%M:%S%z")
        else
          hash[field] = value
        end
      end
      ary[i] = {}
      ary[i] = hash
    end
    ary
  end

However, when in the ary[i] = hash assignment, all ary elements get set to hash.

Is there a better way to convert a record’s timestamp fields? (I don’t need to save the records back to the database.) Also, how can I get the array to capture each individual hash representation of the record?

Input:

[#<Vehicle id: 15001, approved_at: "2011-03-28 10:16:31", entry_date: "2011-03-28 10:16:31">, #<Vehicle id: 15002, approved_at: "2011-03-28 10:16:31", entry_date: "2011-03-28 10:16:31">]

Desired output:

[{"id"=>15001, "approved_at"=>"2011-03-28T10:16:31-0700", "entry_date"=>"2011-03-28T10:16:31-0700"}, {"id"=>15002, "approved_at"=>"2011-03-28T10:16:31-0700", "entry_date"=>"2011-03-28T10:16:31-0700"}]

Answer 1

The problem is that you’re creating one Hash:

def convert_mysql_timestamps(records)
  ary = []
  hash = {}
  #...

and then trying to re-use for each record. You probably want a fresh Hash for each each_with_index iteration:

  def convert_mysql_timestamps(records)
    ary = []
    records.each_with_index do |record, i|
      hash = { }
      record.attributes.each do |field, value|
        #...
      end
      ary[i] = hash
    end
  end