Implement actual update function, lazy-load online_packages

usr/bin/lxcmgr

@@ -56,7 +56,6 @@ def print_apps(packages):
 
 def list_online():
     pm = PkgMgr()
-    pm.fetch_online_packages()
     apps = pm.online_packages['apps']
     if apps:
         print_apps(apps)

usr/lib/python3.6/lxcmgr/pkgmgr.py

@@ -15,6 +15,10 @@ from . import lxcmgr
 from . import svcmgr
 from .paths import LXC_STORAGE_DIR, REPO_CACHE_DIR, REPO_CONF_FILE, REPO_LOCAL_FILE, REPO_LOCK, REPO_SIG_FILE
 
+INSTALL_SCRIPT = 'install.sh'
+UPDATE_SCRIPT = 'update.sh'
+UNINSTALL_SCRIPT = 'uninstall.sh'
+
 class Stage(Enum):
     QUEUED = 1
     DOWNLOAD = 2
@@ -49,10 +53,20 @@ class PkgMgr:
     def __init__(self):
         self.repo_url = None
         self.repo_auth = None
-        self.online_packages = None
+        self._online_packages = None
         with open(REPO_LOCAL_FILE, 'r') as f:
             self.installed_packages = json.load(f)
 
+    @property
+    def online_packages(self):
+        if not self._online_packages:
+            # Fetches and verifies online packages. Can raise InvalidSignature
+            packages = self.get_repo_resource('packages').content
+            packages_sig = self.get_repo_resource('packages.sig').content
+            crypto.verify_signature(REPO_SIG_FILE, packages, packages_sig)
+            self._online_packages = json.loads(packages)
+        return self._online_packages
+
     def save_installed_packages(self):
         with open(REPO_LOCAL_FILE, 'w') as f:
             json.dump(self.installed_packages, f, sort_keys=True, indent=4)
@@ -79,21 +93,26 @@ class PkgMgr:
             raise RepoBadRequest(r.url)
         return r
 
-    def fetch_online_packages(self):
-        # Fetches and verifies online packages. Can raise InvalidSignature
-        packages = self.get_repo_resource('packages').content
-        packages_sig = self.get_repo_resource('packages.sig').content
-        crypto.verify_signature(REPO_SIG_FILE, packages, packages_sig)
-        self.online_packages = json.loads(packages)
-
     @flock.flock_ex(REPO_LOCK)
     def install_app(self, app):
         # Main installation function. Wrapper for download, registration and install script
         if app.name in self.installed_packages['apps']:
             app.stage = Stage.DONE
             return
-        if not self.online_packages:
+        self.download_and_unpack_deps(app)
-            self.fetch_online_packages()
+        # Run setup scripts
+        app.stage = Stage.INSTALL
+        # Run uninstall script to clean previous failed installation
+        self.run_script(app.name, UNINSTALL_SCRIPT)
+        # Build containers and services
+        self.create_containers(self.online_packages['apps'][app.name]['containers'])
+        # Run install script and register the app
+        self.run_script(app.name, INSTALL_SCRIPT)
+        self.register_app(app.name, self.online_packages['apps'][app.name])
+        app.stage = Stage.DONE
+
+    def download_and_unpack_deps(self, app):
+        # Common download and unpack function for install and update
         # Get all packages on which the app and its containers depend and which have not been installed yet
         images = []
         image_deps = [container['image'] for container in self.online_packages['apps'][app.name]['containers'].values()]
@@ -116,16 +135,6 @@ class PkgMgr:
             self.register_image(image, self.online_packages['images'][image])
         self.purge_scripts(app.name)
         self.unpack_scripts(app.name)
-        # Run setup scripts
-        app.stage = Stage.INSTALL
-        # Run uninstall script to clean previous failed installation
-        self.run_uninstall_script(app.name)
-        # Build containers and services
-        self.create_containers(self.online_packages['apps'][app.name]['containers'])
-        # Run install script and register the app
-        self.run_install_script(app.name)
-        self.register_app(app.name, self.online_packages['apps'][app.name])
-        app.stage = Stage.DONE
 
     def download_image(self, app, image):
         # Download image archive and verify hash
@@ -184,14 +193,6 @@ class PkgMgr:
         subprocess.run(['tar', 'xJf', tmp_archive], cwd=os.path.join(REPO_CACHE_DIR, 'apps'), check=True)
         os.unlink(tmp_archive)
 
-    def run_uninstall_script(self, app):
-        # Runs uninstall.sh for an app, if the script is present
-        self.run_script(app, 'uninstall.sh')
-
-    def run_install_script(self, app):
-        # Runs install.sh for a package, if the script is present
-        self.run_script(app, 'install.sh')
-
     def run_script(self, app, script):
         # Runs script for an app, if the script is present
         script_dir = os.path.join(REPO_CACHE_DIR, 'apps', app)
@@ -239,7 +240,7 @@ class PkgMgr:
             app.stage = Stage.DONE
             return
         app.stage = Stage.UNINSTALL
-        self.run_uninstall_script(app.name)
+        self.run_script(app.name, UNINSTALL_SCRIPT)
         self.destroy_containers(self.installed_packages['apps'][app.name]['containers'])
         self.purge_scripts(app.name)
         self.unregister_app(app.name)
@@ -259,17 +260,20 @@ class PkgMgr:
             self.purge_layer(layer)
 
     @flock.flock_ex(REPO_LOCK)
-    def update_app(self, app, item):
+    def update_app(self, app):
         # Main update function.
-        # TODO: Implement actual update
+        self.download_and_unpack_deps(app)
-        uninstall_app(app)
+        # Run setup scripts
-        install_app(app, item)
+        app.stage = Stage.UPDATE
+        # Build containers and services
+        self.create_containers(self.online_packages['apps'][app.name]['containers'])
+        # Run update script and register the app
+        self.run_script(app.name, UPDATE_SCRIPT)
+        self.register_app(app.name, self.online_packages['apps'][app.name])
         app.stage = Stage.DONE
 
     def has_update(self, app):
         # Check if online repository list a newer version of app
-        if not self.online_packages:
-            self.fetch_online_packages()
         if app not in self.online_packages['apps']:
             # Application has been removed from online repo
             return False

usr/lib/python3.6/vmmgr/wsgiapp.py

@@ -174,7 +174,7 @@ class WSGIApp:
         # Application manager view.
         repo_error = None
         try:
-            self.appmgr.pkgmgr.fetch_online_packages()
+            self.appmgr.pkgmgr.fetch_online_packages() # TODO: fetch is now automatic in @property
         except InvalidSignature:
             repo_error = request.session.lang.invalid_packages_signature()
         except Unauthorized: