Mongoose: Adding minlength and maxlength to Schema with String as type

[justin-john]

Add a new feature for minimum length and maximum length to Schema with String as type. This will validate minimum and maximum length to corresponding string in schema.

For example,

var s = new Schema({ name: { type: String, minlength: 5, maxlength: 15 }});

OR

var s = new Schema({ name: { type: String, min: 5, max: 15 }});

[aheckmann]

This belongs as a plugin.

[justin-john]

Can you please be more specific?

I can't find a plugin regarding this feature.

[aheckmann]

You could extend the string schematype similar to how match works.

The plugin would just require mongoose and add the function to mongoose.Schema.Types.String.prototype.

[justin-john]

I think, SchemaString.prototype.minlength and SchemaString.prototype.maxlength can be easily added similar to min and max methods implemented for number schema with slight change. IMO, I don't think it needs to be a plugin as it's similar feature like min and max methods of number schema. So it needs to come as feature provided by mongoose, not by additional plugin.

[aheckmann]

Not gonna happen. Mongoose is bloated enough and exposes the apis necessary to extend it.

[sandesh27]

Hi,

This can be handled using path function like this:

var Person = new Schema({
title : { type: String, required: true }
, age : { type: Number, min: 5, max: 20 }
, meta : {
likes : [String]
, birth : { type: Date, default: Date.now }
}
});

Person.path('title').validate(function (v) {
return v.length > 50;
});

[vedi]

looks like it's on its way to the next release: https://github.com/LearnBoost/mongoose/commit/b96d72440769a4fc038e3934b268b1ec648dd16d

[vedi]

@sandesh27, thank you for workaround

[vkarpov15]

Its in 4.0.0-rc2 :)

[jeremyml]

Here is the documentation for the new minlength validator http://mongoosejs.com/docs/api.html#schema_string_SchemaString-minlength

[tejasmanohar]

Just stumbled upon this. I personally think the ORM/ODM should include as few validations and whatnot built-in, as these are really application concerns, and there are plenty of libraries for this. Keep it lean :)

[gayan27]

how to present date type in schema

[vkarpov15]

See https://mongoosejs.com/docs/schematypes.html#string-validators