Application models

These are object model for data dumps to define behaviors for data collection during dump creation.

class diskette.core.applications.ApplicationConfig(name, models=[], excludes=None, natural_foreign=False, natural_primary=False, comments=None, filename=None, is_drain=None, allow_drain=False, dump_command=None)

Application model to validate and store application details.

TODO: Another name would better to avoid mental clash with Django “AppConfig”. ApplicationModel (+2) ? ApplicationDataDef (0)? ApplicationDefinition (+3) ? DataDefinition (+3) ?

Parameters:

• name (string) – Application name, almost anything but it may be slugified for internal usages so avoid too much longer text and special characters.

• models (list) – List of labels. A label is either an application label like auth or a full model label like auth.user. Labels are validated, they must exists in Django application registry.

Keyword Arguments:

• filename (string) – The filename to use if application dump is to be written in a file. The filename also determine the format used to dump data. If you want another format that the default one you will have to define it from the filename even you don’t plan to write dump to a file. Finally if not given, the filename will be automatically defined with slugified name with default format.

• excludes (list) – The list of excluded model labels that won’t be collected into the application dump. Currently, the excluded labels are not validated.

• natural_foreign (boolean) – Enable usage of natural foreign key.

• natural_primary (boolean) – Enable usage of natural primary key.

• comments (string) – Free text not used internally.

• allow_drain (boolean) – Define if application allows its excluded models to be drained. Default is False to avoid implicit draining of data that may not be wanted.

• dump_command (string) – Custom dump command to use for this specific application instead of default dumpdata. If you have models that use django-polymorphic you should give value polymorphic_dumpdata here.

is_drain

Declare application as a special drain application. This should always be False for a common application, True value is reserved to DrainApplicationConfig.

Type:

boolean

property models

List all fully qualified model labels to include, either implicitely and explicitely from given models argument.

NOTE: models, excludes and retention attributes may be cached since they have no reason to change.

Returns:

Fully qualified model labels.

Return type:

list

property excludes

List all fully qualified model labels to exclude, either implicitely and explicitely from given _excludes argument.

Returns:

Fully qualified model labels.

Return type:

list

property retention

List all fully qualified model labels that are not allowed to be drained from this application.

Included models are never allowed to be drained and exclusions models may be allowed if allow_drain is enabled.

Returns:

Fully qualified model labels that won’t be allowed to be drained. This means labels from models on defaut and possibly the excludes one also if application allows for drainage.

Return type:

list

get_filename(format_extension=None)

Automatically determine filename from Application name and with a format extension name.

Keyword Arguments:

format_extension (string) – Custom extension to use if given.

Returns

string: Filename.

as_config()

Returns Application configuration suitable for dump history.

Keyword Arguments:

• name (boolean) – To include or not the name into the dict.

• commented (boolean) – To include or not the comments into the dict.

Returns

dict: Application data.

as_options()

Returns Application options suitable to pass to dumpdata command.

Keyword Arguments:

• name (boolean) – To include or not the name into the dict.

• commented (boolean) – To include or not the comments into the dict.

Returns

dict: Application data.

validate_includes()

Validate include labels from _models attribute.

validate_excludes()

Validate exclude labels from excludes attribute.

validate()

Validate Application options.

Raises:

ApplicationConfigError – In case of invalid values from options.

class diskette.core.applications.DjangoAppLookupStore(registry=None)

Django application store collects applications and store them with their useful parameters.

This is registry built on top of Django apps to implement methods to easily perform queries alike with Django ORM. It helps to find detailed inclusions and exclusions with application models.

registry

The store registry built as a datalookup.Dataset.

Type:

Dataset

Keyword Arguments:

registry (list) – List of dictionnaries, each dictionnary is an application item with its parameters. If not given, it will be filled automatically from enabled applications using django.apps.

as_dict()

Return the store items with their parameters as a dictionnary.

Returns:

Store items as a dictionnary.

Return type:

dict

as_json()

Return the store items with their parameters as JSON.

Returns:

Store items as JSON.

Return type:

string

classmethod normalize_label(model, app=None)

Return normalized name for a model or FQM label.

Parameters:

model (string or object) – Model name as a string or an object that inherits from django.db.models.base.ModelBase.

Keyword Arguments:

app (string or object) – Either a model object, AppConfig object or a string for an application label.

Returns:

A fully qualified model name composed from app name and model name.

Return type:

string

classmethod is_fully_qualified_labels(labels)

Validate given labels are fully qualified model labels.

Parameters:

labels (list) – List of label to validate.

Returns:

A list of invalid labels.

Return type:

list

get_registry_app_models(app_id, app)

Return model labels for given application.

Internally used to build appstore registry.

Parameters:

• app_id (integer) – An unique id to represent related application.

• app (AppConfig) – The application object from Django apps.

Returns:

A list of dictionnaries for models. Model dictionnary will contains the following items:

id

A simple integer built from the loop, since it is only done internally it should be ensured to be unique.

app_id

Given application id.

unique_id

A special field to help for ordering on models since datalookup does not provide a way to do this. This is a join of app id and model id, both formatted on 4 digits filled by zero.

app

Application label.

name

Model class name.

object

Model class.

label

Fully qualified model label.

Return type:

list

get_registry()

Store all model labels from enabled applications into a registry.

Returns:

A list of dictionnaries for applications. Application dictionnary will contains the following items:

id

A simple integer built from the loop, since it is only done internally it should be ensured to be unique.

verbose_name

Application verbose name.

label

Application label.

pythonpath

Python path to the application itself.

models

A list of application models as returned from method DjangoAppLookupStore.get_registry_app_models.

Return type:

list

get_app(label)

Getter to retrieve a single application from a label.

Parameters:

label (string) – Application label.

Raises:

• MultipleObjectExistsFromAppstore – If there is more than one application object with the same label. This is something that should never happen because of how Django manage applications.

• DoesNotExistsFromAppstore – If there is not any application with the given label.

Returns:

Datalookup node for retrieved application.

Return type:

node

get_model(label)

Getter to retrieve a single application model from a label.

Parameters:

label (string) – Fully qualified model label.

Raises:

• MultipleObjectExistsFromAppstore – If there is more than one application object with the same label. This is something that should never happen because of how Django manage applications.

• DoesNotExistsFromAppstore – If there is not any application with the given label.

Returns:

Datalookup node for retrieved application.

Return type:

node

get_app_model_labels(app)

Return model labels for given application.

Parameters:

app (sring) – Application label.

Returns:

Fully qualified model labels.

Return type:

list

get_all_model_labels()

Return all model labels from all enabled applications.

Returns:

Fully qualified model labels.

Return type:

list

check_unexisting_labels(labels)

Check if given labels exists as app or models in store.

Parameters:

labels (list) – A list of application or FQM label (string) to check.

Returns:

Respectively a list of not found apps and a list of not found models.

Return type:

Tuple

get_models_inclusions(labels, excludes=None)

Returns model nodes for inclusions.

Parameters:

labels (string or list) – A list of App label (string), fully qualified model labels (string) or AppConfig.

Keyword Arguments:

excludes (list) – List of fully qualified model labels to exclude.

Returns:

List of Datalookup nodes.

Return type:

list

get_models_exclusions(labels, excludes=None)

Returns model nodes for exclusions.

Exclusion gather the explicit exclude labels and the intersection between inclusions and missing models related to implied app from inclusion labels.

Parameters:

labels (string or list) – App label or fully qualified model labels.

Keyword Arguments:

excludes (list) – List of fully qualified model labels.

Returns:

List of Datalookup nodes.

Return type:

list

class diskette.core.applications.DrainApplicationConfig(*args, **kwargs)

Special application to drain remaining models from apps.

On default a drain will dump anything that have not been defined from apps. Its base goal is to dump data from undefined applications.

drain_excluded

If enabled, the drain will accept to drain exclusion from applications which allow it. Else the drain will exclude also the application exclusion. Default is disabled.

Type:

boolean

property excludes

Just returns exclude labels as given since drain excludes are meaningful enough.

Returns:

Fully qualified model labels.

Return type:

list