確保數組中只有一個元素具有給定屬性

Question

我想在包含數組的集合上設置布爾標誌。隨着數據的一個例子：

{ 
    _id: "12341234", 
    name: { 
    first: 'Jeff', 
    last: 'Jefferson' 
    }, 
    emails: [{ 
    address: 'fake@fake.org', 
    verified: true, 
    primary: true 
    }, { 
    address: 'fake@fake.net', 
    verified: true, 
    primary: false 
    }] 
} 

在此表中的每個條目，我需要的電子郵件的陣列永遠只能有一個條目是primary: true。

與表的鍵，你可以這樣做如下，以確保其唯一性：

Meteor._ensureIndex({ 'name.last': 1 }, { unique: 1 }); 

會不會有一種方法可以做到這一點的一個條目的陣列上？

Answer 1

看看添加自定義的驗證與aldeed：簡單模式，連接到您的收藏與aldeed：collections2

customUsers = new Mongo.Collection('customUsers'); 
customUsers.attachSchema(new SimpleSchema({ 

    name: { 
    type: new SimpleSchema({ 
     first: { type: String}, 
     last: { type: String}, 
    }), 
    }, 

    emails: { 
    type: Array, 
    custom: function() { 
     if (_.compact(_.pluck(this.value, 'primary')).length !== 1) { 
     return 'NotOnePrimaryEmail'; 
     } 
    }, 
    }, 
    'emails.$': { 
    type: Object, 
    }, 
    'emails.$.address': { 
    type: String, 
    regEx: SimpleSchema.RegEx.Email, 
    }, 
    'emails.$.verified': { 
    type: Boolean, 
    }, 
    'emails.$.primary': { 
    type: Boolean, 
    }, 

})); 

SimpleSchema.messages({ 
    NotOnePrimaryEmail: 'You must have one, and only one, email marked as primary', 
}); 

if (Meteor.isServer) { 
    Meteor.startup(function() { 

    objValid = { 
     name: { 
     first: 'Jeff', 
     last: 'Jefferson', 
     }, 
     emails: [{ 
     address: 'fake@fake.org', 
     verified: true, 
     primary: true, 
     }, { 
     address: 'fake@fake.net', 
     verified: true, 
     primary: false, 
     },], 
    }; 

    objNoPrimary = { 
     name: { 
     first: 'Jeff', 
     last: 'Jefferson', 
     }, 
     emails: [{ 
     address: 'fake@fake.org', 
     verified: true, 
     primary: false, 
     }, { 
     address: 'fake@fake.net', 
     verified: true, 
     primary: false, 
     },], 
    }; 

    objMultiplePrimary = { 
     name: { 
     first: 'Jeff', 
     last: 'Jefferson', 
     }, 
     emails: [{ 
     address: 'fake@fake.org', 
     verified: true, 
     primary: true, 
     }, { 
     address: 'fake@fake.net', 
     verified: true, 
     primary: true, 
     },], 
    }; 

    [objValid, objNoPrimary, objMultiplePrimary].forEach(
     function(obj) { 
     try { 
      customUsers.insert(obj); 
      console.log('Object was valid, inserted into collection'); 
     } catch (err) { 
      console.log('Error: ' + err.sanitizedError.reason); 
     } 
     } 
    ); 
    }); 
} 

從服務器控制檯輸出：

~/test/schema$ meteor 
[[[[[ ~/test/schema ]]]]]      

=> Started proxy.        
=> Started MongoDB.       
=> Started your app.       

=> App running at: http://localhost:3000/ 
I20151008-15:04:15.280(13)? Object was valid, inserted into collection 
I20151008-15:04:15.281(13)? Error: You must have one, and only one, email marked as primary 
I20151008-15:04:15.281(13)? Error: You must have one, and only one, email marked as primary