在Firebase中构建聊天应用程序的数据 [英] Structuring data for chat app in Firebase

问题描述

按照Firebase指南，为结构化数据进行聊天应用程序。他们建议如下所示的结构。

  {
 //聊天只包含每个对话的元信息
 //存储在聊天记录的独特ID 
chats：{
one：{
title：Historical Tech Pioneers，
lastMessage：ghopper：发现继电器故障原因： ，
timestamp：1459361875666 
}，
two：{...}，
three：{...} 
 }，
 
 //对话成员很容易访问
 //并通过聊天对话存储ID 
members：{
 //我们将讨论索引像下面这样
one：{
ghopper：true，
alovelace：true，
eclarke：true 
}，
two：{...}，
three：{...} 
}，
 
 //消息与我们想要迭代的数据分开快速
 //但仍然很容易分页和查询，并通过聊天组织
 // converation ID 
messages：{
one：{
m1 ：{ 
name：eclarke，
message：继电器似乎有故障。，
timestamp：1459361875337 
}，
 m2：{...}，
m3：{...} 
}，
two：{...}，
three： {...} 
} 
} 
  

如何组织我的用户数据，以便我可以轻松地显示所有聊天的列表，并为每个聊天显示最后的消息和时间戳。如果我做了以下结构：

$ $ p $ users：{
ghopper：{
名称：Gary Hopper，
chats：{
one：true，
two：true
}
}，
alovelace{...}
}，


（swift）：

  ref.child（users ）.child（ghopper）。child（chats）。observeSingleEventOfType（.Value，withBlock：{（snapshot）in 
 // do something with data 
} 
  

然而，我不会在这个快照中使用lastMessage和timestamp，我需要做些什么来访问这些数据呢？ p>



• 为每个用户复制所有这些数据，即添加用户/ ghopper /聊天/一个/ {lastMessage：ghopper：发现中继故障。原因：飞蛾。，timestamp：1459361875666}


• 为每个查询chats / specificGroupId聊天，该用户是（添加多个列表）的一部分？


• 其他一些方法？
  
  

  解决方案

  
  

  如何构建我的用户数据，以便我可以轻松地显示
  列表中的所有聊天内容，并为每个聊天显示
  最后一条消息和时间戳。

  
  

  通过添加聊天节点中的用户来改变聊天结构。

   chats：{
  one：{
  title：Historical Tech Pioneers，
  lastMessage：ghopper ：
  timestamp：1459361875666 
   users 
   uid_1：true 
   uid_3：true 
  }，
  两个：{...}，
    

  然后您可以深入查询特定用户的所有聊天记录部分 - 这将返回聊天uid_3参与
  $ b $ pre $ chatsRef.queryOrderedByChild（users / uid_3）。queryEqualToValue（true ）
.observeSingle EventOfType（.Value，withBlock：{snapshot in

//.Value可以返回快照中的多个节点，以便迭代它们
在snapshot.children中的子节点{
let lastmsg = child.value [lastMessage]为！字符串
让timestamp = child.value [timestamp] as！字符串
print（lastmsg）
print（timestamp）
}
}）


  请注意，当用户通过auth.uid创建时，每个firebase用户都有一个谨慎的用户标识。这应该（通常）作为每个用户的关键。

  
  

  Im following Firebase guide to structuring data for a chat app. They suggest the structure as seen below.

  {
    // Chats contains only meta info about each conversation
    // stored under the chats's unique ID
    "chats": {
      "one": {
        "title": "Historical Tech Pioneers",
        "lastMessage": "ghopper: Relay malfunction found. Cause: moth.",
        "timestamp": 1459361875666
      },
      "two": { ... },
      "three": { ... }
    },
  
    // Conversation members are easily accessible
    // and stored by chat conversation ID
    "members": {
      // we'll talk about indices like this below
      "one": {
        "ghopper": true,
        "alovelace": true,
        "eclarke": true
      },
      "two": { ... },
      "three": { ... }
    },
  
    // Messages are separate from data we may want to iterate quickly
    // but still easily paginated and queried, and organized by chat
    // converation ID
    "messages": {
      "one": {
        "m1": {
          "name": "eclarke",
          "message": "The relay seems to be malfunctioning.",
          "timestamp": 1459361875337
        },
        "m2": { ... },
        "m3": { ... }
      },
      "two": { ... },
      "three": { ... }
    }
  }
  

  How do I structure my user data so that I can easily display a list of all of the chats they are part of and for each one of them display the last message and timestamp. If I do the following structure:

     "users": {
      "ghopper": {
        "name": "Gary Hopper",
        "chats": {
            "one: true",
            "two": true
        }
      },
      "alovelace" { ... }
    },
  

  I can easily get a list of each chat group for a specific user, for example ghopper, by doing (in swift):

  ref.child("users").child("ghopper").child("chats").observeSingleEventOfType(.Value, withBlock: { (snapshot) in
    //do something with data
  }
  

  However I won't have the lastMessage and timestamp in this snapshot. What do I need to do to access this data?

  • Duplicate all this data for each user? i.e adding users/ghopper/chats/one/ {"lastMessage": "ghopper: Relay malfunction found. Cause: moth.", "timestamp" : 1459361875666}
  • Make a query for "chats/specificGroupId" for each chat that the user is part of (adding multiple listners)?
  • Some other way?

  解决方案

  How do I structure my user data so that I can easily display a list of all of the chats they are part of and for each one of them display the last message and timestamp.

  Change the chats structure a tad by adding users who are in the chat node

  "chats": {
      "one": {
        "title": "Historical Tech Pioneers",
        "lastMessage": "ghopper: Relay malfunction found. Cause: moth.",
        "timestamp": 1459361875666
        users
         uid_1: true
         uid_3: true
      },
      "two": { ... },
  

  Then you can deep query for all chats a particular user is part of - this will return the chats uid_3 is involved in

  chatsRef.queryOrderedByChild("users/uid_3").queryEqualToValue(true)
       .observeSingleEventOfType(.Value, withBlock: { snapshot in
  
       //.Value can return multiple nodes within the snapshot so iterate over them
       for child in snapshot.children {
            let lastmsg = child.value["lastMessage"] as! String
            let timestamp = child.value["timestamp"] as! String
            print(lastmsg)
            print(timestamp)
       }     
  })
  

  Note that each firebase user has a discreet user id obtained when the user is created via auth.uid. This should (generally) be used as the key for each user.

  这篇关于在Firebase中构建聊天应用程序的数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！