repository·master·Indexed 23 days ago
https://github.com/openstack/horizonHorizon is a Django-based dashboard providing a web-based interface for OpenStack services. It serves as an extensible framework for building dashboards using reusable components. Documentation covers administrative tasks such as managing roles and compute flavors, customizing the visual appearance (logos, colors, and themes), and configuring the dashboard for HTTP and HTTPS deployments via local_settings.py and Apache.
The Essex release includes significant enhancements for managing Nova resources:
The Horizon core reviewer team manages the project's health, quality, and community. Their responsibilities include:
Horizon utilizes three main types of testing to ensure stability and quality:
You can configure the directory where integration test screenshots are saved via the horizon.conf file. The default value is ./integration_tests_screenshots.
Horizon settings are organized into four main categories:
Horizon provides a mechanism to programmatically hide, show, and rename form fields based on the selection in a trigger field. This is achieved using specific CSS classes and HTML data attributes.
To create a trigger, use a field with a select input widget that has:
switchable.data-slug attribute (e.g., data-slug='source').To create a field that reacts to the trigger, use a field that has:
switched.data-switch-on attribute that matches the trigger's data-slug (e.g., data-switch-on='source').data-<slug>-<value>="<desired label>" (e.g., data-source-cidr='CIDR').If the trigger's value does not match any defined state attribute for a switched field, that field is hidden.
Avoid having a single switched field listen to multiple triggers via data-switch-on. This behavior is unpredictable. Instead, create independent fields for each trigger and merge their results during the form's clean() or handle() phase.
source = forms.ChoiceField(
label=_('Source'),
choices=[
('cidr', _('CIDR')),
('sg', _('Security Group'))
],
widget=forms.ThemableSelectWidget(attrs={
'class': 'switchable',
'data-slug': 'source'
})
)
cidr = fields.IPField(
label=_("CIDR"),
required=False,
widget=forms.TextInput(attrs={
'class': 'switched',
'data-switch-on': 'source',
'data-source-cidr': _('CIDR')
})
)
security_group = forms.ChoiceField(
label=_('Security Group'),
required=False,
widget=forms.ThemableSelectWidget(attrs={
'class': 'switched',
'data-switch-on': 'source',
'data-source-sg': _('Security Group')
})
)To mitigate the performance overhead of database-backed sessions, you can use the cached_db back end. This hybrid approach uses both your database and your caching infrastructure (like Memcached or Redis) to perform write-through caching and efficient retrieval.
Requirement: You must have both a database and a cache configured in local_settings.py.
SESSION_ENGINE = "django.contrib.sessions.backends.cached_db"To prevent exposing sensitive or obscure data from OpenStack APIs to the end-user, do not propagate direct exception messages to the UI.
Horizon catches API exceptions and normalizes them using horizon.exceptions.handle. This ensures error messages are clean and potentially translatable (though API messages themselves are not translatable).
The openstack_dashboard/themes/default/bootstrap/ directory is used to customize Bootstrap components and variables.
_variables.scss: Define or alter Bootstrap variables to change the look and feel of the default theme.components/: Contains SCSS overrides for specific Bootstrap components (e.g., tables, navbars)._styles.scss: Imports the SCSS defined for each component in the components/ directory.During the migration to oslo.config, existing Django settings are mapped to specific INI sections and option names. Prefixes are typically dropped, and dictionary-based settings are broken down into individual options.
Mapping Rules:
OPENSTACK_KEYSTONE_DEFAULT_ROLE maps to [keystone] default_role.OPENSTACK_KEYSTONE_BACKEND is split into multiple options:OPENSTACK_KEYSTONE_BACKEND['name'] $\rightarrow$ [keystone] backend_nameOPENSTACK_KEYSTONE_BACKEND['can_edit_user'] $\rightarrow$ [keystone] backend_can_edit_user[default] section is reserved for common settings like DEBUG or LOGGING.Horizon provides a component-based system for building tabbed interfaces. The architecture relies on three main layers:
TableTab for data-heavy views.TabGroup in the dashboard.This system supports advanced features like dynamic AJAX loading and simplified templating/styling.
Horizon's horizon.tables module provides a reusable API for building data-driven interfaces using three core components:
DataTable to a web request and provides the data.When using a DataTableView, the request follows this lifecycle:
preempt=True) are checked.from horizon import tables
from .tables import MyTable
class MyTableView(tables.DataTableView):
table_class = MyTable
template_name = "my_app/my_table_view.html"
def get_data(self):
return my_api.objects.list()