MongoEngine and WTForms

flask-mongoengine automatically generates WTForms from MongoEngine models:

from import model_form

class User(db.Document):
    email = db.StringField(required=True)
    first_name = db.StringField(max_length=50)
    last_name = db.StringField(max_length=50)

class Content(db.EmbeddedDocument):
    text = db.StringField()
    lang = db.StringField(max_length=3)

class Post(db.Document):
    title = db.StringField(max_length=120, required=True, validators=[validators.InputRequired(message='Missing title.'),])
    author = db.ReferenceField(User)
    tags = db.ListField(db.StringField(max_length=30))
    content = db.EmbeddedDocumentField(Content)

PostForm = model_form(Post)

def add_post(request):
    form = PostForm(request.POST)
    if request.method == 'POST' and form.validate():
        # do something
    return render_template('add_post.html', form=form)

For each MongoEngine field, the most appropriate WTForm field is used. Parameters allow the user to provide hints if the conversion is not implicit::

PostForm = model_form(Post, field_args={'title': {'textarea': True}})

Supported parameters:

For fields with choices:

  • multiple to use a SelectMultipleField

  • radio to use a RadioField

For StringField:

  • password to use a PasswordField

  • textarea to use a TextAreaField

For ListField:

  • min_entries to set the minimal number of entries

(By default, a StringField is converted into a TextAreaField if and only if it has no max_length.)

Supported fields

  • StringField

  • BinaryField

  • URLField

  • EmailField

  • IntField

  • FloatField

  • DecimalField

  • BooleanField

  • DateTimeField

  • ListField (using wtforms.fields.FieldList )

  • SortedListField (duplicate ListField)

  • EmbeddedDocumentField (using wtforms.fields.FormField and generating inline Form)

  • ReferenceField (using wtforms.fields.SelectFieldBase with options loaded from QuerySet or Document)

  • DictField

Not currently supported field types:

  • ObjectIdField

  • GeoLocationField

  • GenericReferenceField