Yii2-substitution module development

The goal is to implement an extension for Yii2 framework which should allow users to specify substitutions (out of office). A substitution is simply a record which states that a certain user X is replaced by user Z starting from date-time S until date-time E. For each inserted substitution the user should be able to specify: • a note • if notifications directed to him (user X) should be sent only to user Z or also to him. This option should have a default value configurable at extension level It should be possible to place the button for inserting a new substitution in every view by the mean of a widget . When this button is pressed user is taken to the insert action of the substitution controller. You can style the button as a ‘normal’ ‘default’ button: [login to view URL] The extension should implement (via migration) and check the following RBAC permissions: • “manage_own_substitutions”: one stating that the user can insert substitutions for himself • “manage_all_substitutions”: one stating that the user can manage (see, insert, update, delete) all the substitutions presents in the system The extension should respect the following requirements: • a user should not be able to edit his own substitutions which has the end date in the past unless he has the “manage_all_substitutions” permission • provide a full CRUD for managing the substitutions, and display records according to user permissions. You can start generating the base code with Gii • implement delete actions as “soft deletes” (a flag indicating the record is deleted) • implement translation system for multiple languages: [login to view URL] . Its ok to implement it in english but it should be available a working translation file where we can insert italian translation. Time estimation: 5h