Module decorators

A decorator to return a property that returns the first value of list attribute corresponding to the provided list property name.

For example, if the list property is top_albums, then the decorator returns a property that returns the first (top most) album.

Parameters:

• list_property_name (str) - the name of the list property. Like 'top_albums'.

Returns: property

a property that returns the first value of list attribute corresponding to the provided list property name

A decorator to cache the atrribute of the object. When called for the first time, the value of the attribute is retrived and saved in an instance variable. Later calls return the copy of the cached value, so that the original cached value cannot be modified.

Parameters:

• func (function) - the getter function of the attribute

Returns: property

a property that wraps the getter function of the attribute

A decorator to check if the current user is authenticated or not. Used only on the functions that need authentication. If not authenticated then an exception is raised.

Parameters:

• func (function) - a function that needs to be authentication, for being called

Returns: function

a function that wraps the original function

Raises:

• AuthenticationFailedError - If the user is not authenticated, then an exception is raised.