MongoError:无法识别的管道阶段名称:'$ addFields'。
“ Mongoose ”:“^ 4.5.8”
我的源代码:
Post.aggregate(
[{
$addFields: {
userName: { $concat: [ "$author.firstName", " ", "$author.lastName" ] }
}
//$project: { userName: { $concat: [ "$author.firstName", " ", "$author.lastName" ] } } //this is ok!
}],
function (err, result) {
if (err) {
console.log(err);
return;
}
console.log(result);
}
)
帖子模型:
let schema = {
id: "post",
properties: {
content: {type: "string"},
author: {
type: "object",
id: {type: "string"},
avatar: {type: "string"},
firstName: {type: "string"},
lastName: {type: "string"},
status: {type: "string"}
},
category: {
type: "object",
id: {type: "string"},
name: {type: "string"}
},
images: {
type: "array",
items: {
type: "object",
properties: {
filePath: {type: "string"},
}
}
},
video: {
type: "object",
thumbnail: {type: "string"},
filePath: {type: "string"}
},
likes: {
type: "array",
items: {
type: "object",
properties: {
userId: {type: "string"},
status: {type: "string"},
_id : {type: "string", default: null}
}
}
},
shares: {
type: "array",
items: {
type: "object",
properties: {
userId: {type: "string"},
status: {type: "string"},
destination: {type: "string"}, //FACEBOOK|TWISTER|GOOGLE
_id : {type: "string", default: null}
}
}
},
favorites: {
type: "array",
items: {
type: "object",
properties: {
userId: {type: "string"},
status: {type: "string"},
_id : {type: "string", default: null}
}
}
},
comments: {
type: "array",
items: {
type: "object",
properties: {
commentId: {type: "string"},
_deleted: {type: "Date", default: ''},
_id : {type: "string", default: null}
}
}
},
_created: {type: "Date", default: Date.now},
_deleted: {type: "Date", default: ''},
_updated: {type: "Date", default: ''}
}
最佳答案
$addFields
在Mongo 3.4版本中引入。如您所评论的那样,您正在使用mongo 3.2.9,则上述查询将不起作用。
如果由于某种原因而无法更新mongo版本,则必须使用以下方法来遍历每个文档并设置新字段
Post.find({}).forEach(function(post){
post.findOneAndUpdate({_id: post._id},
{$set: {userName: post.author.firstName + " " + post.author.lastName }})
});