为任何更新查询增加Mongoose文档版本的简便方法？ [英] Easy way to increment Mongoose document versions for any update queries?

问题描述

我想开始利用Mongooses文档版本控制（__v key）。我实际上在增加版本值时遇到了问题，然后我发现在执行查询时你必须添加 this.increment（）。

I want to start taking advantage of Mongooses document versioning (__v key). I was having an issue actually incrementing the version value, then I found that you have to add this.increment() when executing a query.

有没有办法自动增加？目前，我刚刚将其添加到 pre 中间件以获取更新类型查询：

Is there a way to have automatically incremented? For now, I just added it to the pre middleware for a update-type queries:

module.exports = Mongoose => {
    const Schema = Mongoose.Schema

    const modelSchema = new Schema( {
        name: Schema.Types.String,
        description: Schema.Types.String
    } )

    // Any middleware that needs to be fired off for any/all update-type queries
    _.forEach( [ 'save', 'update', 'findOneAndUpdate' ], query => {
        // Increment the Mongoose (__v)ersion for any updates
        modelSchema.pre( query, function( next ) {
            this.increment()
            next()
        } )
    } )
}

哪个似乎有用..但我觉得在Mongoose中已经有办法做到这一点..我错了吗？

Which seems to work.. But I kinda thought there would already be a way to do this within Mongoose.. am I wrong?

推荐答案

我会说这是要走的路。 预中间件完全适合这种需求，我不知道其他任何方式。事实上，这就是我在所有模式中所做的事情。

I'd say this is the way to go. pre middleware fits exactly this need, and I don't know any other way. In fact this is what I'm doing in all my schemas.

你需要注意的是， document 之间的区别和查询中间件。
文档中间件执行 init ，验证，保存和删除操作。在那里，这个指的是文件：

What you need to be aware of though, is the difference between document and query middleware. Document middleware are executed for init, validate, save and remove operations. There, this refers to the document:

schema.pre('save', function(next) {
  this.increment();
  return next();
});

查询中间件执行 count ，查找， findOne ， findOneAndRemove ， findOneAndUpdate 和更新操作。在那里，这个指的是查询对象。更新此类操作的版本字段如下所示：

Query middleware are executed for count, find, findOne, findOneAndRemove, findOneAndUpdate and update operations. There, this refers to the query object. Updating the version field for such operations would look like this:

schema.pre('update', function( next ) {
  this.update({}, { $inc: { __v: 1 } }, next );
});

资料来源： mongoose文档。

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