Group an array of hashes by two conditions with Ruby

Question

I have an array of hashes like so, I have removed some of the records for presentation purposes.

[
  {
    "id"=>425343308605714432, 
    "text"=>"Hello", 
    "sender"=> {
      "id"=>1375480994, 
      "name"=>"Rocket"
    }, 
    "sender_id"=>1375480994, 
    "recipient"=> {
      "id"=>24766510,
      "name"=>"Max Rose-Collins"
    }, 
    "recipient_id"=>24766510, 
    "recipient_id_str"=>"24766510", 
    "recipient_screen_name"=>"maxrosecollins", 
    "created_at"=>"Mon Jan 20 19:05:21 +0000 2014" 
  },
  {
    "id"=>413305410666639361,  
    "text"=>"How are you", 
    "sender"=> {
      "id"=>24766510,  
      "name"=>"Max Rose-Collins"
    }, 
    "sender_id"=>24766510, 
    "sender_screen_name"=>"maxrosecollins", 
    "recipient"=> {
      "id"=>1375480994, 
      "name"=>"Rocket"
    }, 
    "recipient_id"=>1375480994, 
    "recipient_id_str"=>"1375480994", 
    "recipient_screen_name"=>"Rocket", 
    "created_at"=>"Wed Dec 18 13:51:03 +0000 2013"
  }
]

This array of hashes also contains other messages between other users. I want to arrange this into conversations which contain the sent and received messages between two users. I have tried using

.group_by { |r| [r['recipient_id'], r['sender_id']] }

but this doesn't group them how I would have thought. It makes two groups one sent and the other received.

{
  [1375480994, 24766510]=>[removed for presentation], 
  [24766510, 1375480994]=>[removed for presentation],
  [24766510, 146385359]=>[removed for presentation],
  [146385359, 24766510]=>[removed for presentation],
}

How can I merge these two hashes into one so I have the whole of the conversation in one place, like a threaded conversation?

Answer 1

为了通过对话对它们进行分组，您可以将sort方法添加到group_by函数中：

.group_by{ |r| r.values_at('recipient_id', 'sender_id').sort }