Improve application management-related logic

core/Errors.py

@@ -22,6 +22,10 @@ class UnsupportedApplicationVersionError(Exception):
     pass
 
 
+class ApplicationAlreadyInstalledError(Exception):
+    pass
+
+
 class MissingSubscriptionError(Exception):
     pass
 

core/controllers/ApplicationVersionController.py

@@ -1,5 +1,6 @@
-from core.Errors import FileIntegrityError, UnsupportedApplicationVersionError
+from core.Errors import FileIntegrityError, UnsupportedApplicationVersionError, ApplicationAlreadyInstalledError
 from core.controllers.ApplicationController import ApplicationController
+from core.models.session.Application import Application
 from core.models.session.ApplicationVersion import ApplicationVersion
 from core.observers.ApplicationVersionObserver import ApplicationVersionObserver
 from core.observers.ConnectionObserver import ConnectionObserver
@@ -19,11 +20,21 @@ class ApplicationVersionController:
         return ApplicationVersion.find(application_code, version_number)
 
     @staticmethod
-    def install(application_version: ApplicationVersion, application_version_observer: Optional[ApplicationVersionObserver] = None, connection_observer: Optional[ConnectionObserver] = None):
+    def get_all(application: Optional[Application] = None):
+        return ApplicationVersion.all(application)
+
+    @staticmethod
+    def install(application_version: ApplicationVersion, reinstall: bool = False, application_version_observer: Optional[ApplicationVersionObserver] = None, connection_observer: Optional[ConnectionObserver] = None):
 
         if not application_version.is_supported():
             raise UnsupportedApplicationVersionError('The application version in question is not supported.')
 
+        if reinstall is True:
+            ApplicationVersionController.uninstall(application_version)
+
+        if application_version.is_installed():
+            raise ApplicationAlreadyInstalledError('The application in question is already installed.')
+
         from core.controllers.ConnectionController import ConnectionController
         ConnectionController.with_preferred_connection(application_version, task=ApplicationVersionController.__install, application_version_observer=application_version_observer, connection_observer=connection_observer)
 

core/models/session/Application.py

@@ -39,6 +39,11 @@ class Application(Model):
         Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition)
         return Model._query_all('SELECT * FROM applications', Application.factory)
 
+    @staticmethod
+    def exists(code: str):
+        Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition)
+        return Model._query_exists('SELECT * FROM applications WHERE code = ?', [code])
+
     @staticmethod
     def truncate():
         Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition, drop_existing=True)

core/models/session/ApplicationVersion.py

@@ -1,5 +1,6 @@
 from core.Constants import Constants
 from core.models.Model import Model
+from core.models.session.Application import Application
 from dataclasses import dataclass, field
 from dataclasses_json import config, Exclude
 from datetime import datetime
@@ -81,6 +82,17 @@ class ApplicationVersion(Model):
         Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition)
         return Model._query_one('SELECT * FROM application_versions WHERE application_code = ? AND version_number = ? LIMIT 1', ApplicationVersion.factory, [application_code, version_number])
 
+    @staticmethod
+    def all(application: Optional[Application] = None):
+
+        Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition)
+
+        if application is None:
+            return Model._query_all('SELECT * FROM application_versions', ApplicationVersion.factory)
+
+        else:
+            return Model._query_all('SELECT * FROM application_versions WHERE application_code = ?', ApplicationVersion.factory, [application.code])
+
     @staticmethod
     def exists(application_code: str, version_number: str):
         Model._create_table_if_not_exists(table_name=_table_name, table_definition=_table_definition)