node.js – 使用mongoose hook重试保存重复键错误

pagescheR_933_11845@a.pre('save',function(next){
    var page = this;

    page.createdDT = new Date();
    page.updatedDT = new Date();

    page.slug = page.title.slug(); // create slug from title

    var re = new RegExp(page.slug,'i');

    mongoose.models["page"].find({slug: { $regex: rE}},function(err,pages){
        // slug doesn't exist,good to go
        if(!err && !pages) return next();

        var slugs = [];

        // let's get all slugs
        pages.forEach(function(pagE){
            slugs.push(page.slug);
        });

        // keep increasing `i` until slug is unique
        // set i to 1 to avoid Hello-0 
        var i = 1;
        var tempSlug = page.slug;
        while(slugs.indexOf(tempSlug) >= 0){
            tempSlug = page.slug + '-' + i;
            i++;
        }

        //unique slug for example "Hello-2"
        page.slug = tempSlug;
        next();
    }); 
});