Advanced Configuration¶
Security¶
To block or set the allowed permissions on a view, just set the base_permissions property with the base permissions
class GroupModelView(ModelView):
datamodel = SQLAInterface(Group)
base_permissions = ['can_add','can_delete']
With this initial config, the framework will only create ‘can_add’ and ‘can_delete’ permissions on GroupModelView as the only allowed. So users and even the administrator of the application will not have the possibility to add list or show permissions on Group table view. Base available permission are: can_add, can_edit, can_delete, can_list, can_show. More detailed info on Security
Custom Fields¶
Custom Model properties can be used on lists. This is useful for formatting values like currencies, time or dates. or for custom HTML. This is very simple to do, first define your custom property on your Model and then use the @renders decorator to tell the framework to map you class method with a certain Model property:
from flask_appbuilder.models.decorators import renders
class MyModel(Model):
id = Column(Integer, primary_key=True)
name = Column(String(50), unique = True, nullable=False)
custom = Column(Integer(20))
@renders('custom')
def my_custom(self):
# will render this columns as bold on ListWidget
return Markup('<b>' + self.custom + '</b>')
On your view reference your method as a column on list:
class MyModelView(ModelView):
datamodel = SQLAInterface(MyTable)
list_columns = ['name', 'my_custom']
Base Filtering¶
To filter a views data, just set the base_filter property with your base filters. These will allways be applied first on any search.
It’s very flexible, you can apply multiple filters with static values, or values based on a function you define. On this next example we are filtering a view by the logged in user and with column name starting with “a”
base_filters is a list of lists with 3 values [[‘column name’,FilterClass,’filter value],…]:
from flask import g
from flask_appbuilder import ModelView
from flask_appbuilder.models.sqla.interface import SQLAInterface
from flask_appbuilder.models.sqla.filters import FilterEqualFunction, FilterStartsWith
# If you're using Mongo Engine you should import filters like this, everything else is exactly the same
# from flask_appbuilder.models.mongoengine.filters import FilterStartsWith, FilterEqualFunction
from .models import MyTable
def get_user():
return g.user
class MyView(ModelView):
datamodel = SQLAInterface(MyTable)
base_filters = [['created_by', FilterEqualFunction, get_user],
['name', FilterStartsWith, 'a']]
Since version 1.5.0 you can use base_filter with dotted notation, necessary joins will be handled for you on the background. Study the following example to see how:
https://github.com/dpgaspar/Flask-AppBuilder/tree/master/examples/extendsecurity
Default Order¶
Use a default order on your lists, this can be overridden by the user on the UI. Data structure (‘col_name’:’asc|desc’):
class MyView(ModelView):
datamodel = SQLAInterface(MyTable)
base_order = ('my_col_to_be_ordered','asc')
Template Extra Arguments¶
You can pass extra Jinja2 arguments to your custom template, using extra_args property:
class MyView(ModelView):
datamodel = SQLAInterface(MyTable)
extra_args = {'my_extra_arg':'SOMEVALUE'}
show_template = 'my_show_template.html'
Your overriding the ‘show’ template to handle your extra argument. You can still use F.A.B. show template using Jinja2 blocks, take a look at the Templates chapter
Forms - Override automatic form creation¶
Define your own Add, Edit forms using WTForms to override the automatic form creation:
class MyView(ModelView):
datamodel = SQLAInterface(MyModel)
add_form = AddFormWTF
Forms - Add or remove fields¶
Define what columns will be included on Add or Edit forms, for example if you have automatic fields like user or date, you can remove them from the Add Form:
class MyView(ModelView):
datamodel = SQLAInterface(MyModel)
add_columns = ['my_field1', 'my_field2']
edit_columns = ['my_field1']
To contribute with any additional fields that are not on a table/model, for example a confirmation field:
class ContactModelView(ModelView):
datamodel = SQLAInterface(Contact)
add_form_extra_fields = {
'extra': TextField(gettext('Extra Field'),
description=gettext('Extra Field description'),
widget=BS3TextFieldWidget())
}
Forms - Readonly fields¶
Define/override readonly fields like this, first define a new Readonly field:
from flask_appbuilder.fieldwidgets import BS3TextFieldWidget
class BS3TextFieldROWidget(BS3TextFieldWidget):
def __call__(self, field, **kwargs):
kwargs['readonly'] = 'true'
return super(BS3TextFieldROWidget, self).__call__(field, **kwargs)
Next override your field using your new widget:
class ExampleView(ModelView):
datamodel = SQLAInterface(ExampleModel)
edit_form_extra_fields = {
'field2': TextField('field2', widget=BS3TextFieldROWidget())
}
Readonly select fields are a special case, but it’s solved in a simpler way:
# Define the field query
def department_query():
return db.session.query(Department)
class EmployeeView(ModelView):
datamodel = SQLAInterface(Employee)
list_columns = ['employee_number', 'full_name', 'department']
# override the 'department' field, to make it readonly on edit form
edit_form_extra_fields = {
'department': QuerySelectField(
'Department',
query_factory=department_query,
widget=Select2Widget(extra_classes="readonly")
)
}
Forms - Custom validation rules¶
Contribute with your own additional form validations rules. Remember FAB will automatically validate any field that is defined on the database with Not Null (Required) or Unique constraints:
class MyView(ModelView):
datamodel = SQLAInterface(MyModel)
validators_columns = {
'my_field1':[EqualTo('my_field2', message=gettext('fields must match'))]
}