Merge pull request #670 from YunoHost/check-service-up-before-app-scripts

[enh] Check that required services are up before running app install and upgrade

locales/en.json

@@ -4,6 +4,7 @@
     "admin_password": "Administration password",
     "admin_password_change_failed": "Unable to change password",
     "admin_password_changed": "The administration password has been changed",
+    "app_action_cannot_be_ran_because_required_services_down": "This app requires some services which are currently down. Before continuing, you should try to restart the following services (and possibly investigate why they are down) : {services}",
     "admin_password_too_long": "Please choose a password shorter than 127 characters",
     "app_already_installed": "{app:s} is already installed",
     "app_already_installed_cant_change_url": "This app is already installed. The url cannot be changed just by this function. Look into `app changeurl` if it's available.",

src/yunohost/app.py

@@ -42,7 +42,7 @@ from yunohost.utils.error import YunohostError
 from moulinette.utils.log import getActionLogger
 from moulinette.utils.filesystem import read_json
 
-from yunohost.service import service_log, _run_service_command
+from yunohost.service import service_log, service_status, _run_service_command
 from yunohost.utils import packages
 from yunohost.log import is_unit_operation, OperationLogger
 
@@ -623,6 +623,7 @@ def app_upgrade(auth, app=[], url=None, file=None):
 
         # Check requirements
         _check_manifest_requirements(manifest, app_instance_name=app_instance_name)
+        _check_services_status_for_app(manifest.get("services", []))
 
         app_setting_path = APPS_SETTING_PATH + '/' + app_instance_name
 
@@ -778,6 +779,7 @@ def app_install(operation_logger, auth, app, label=None, args=None, no_remove_on
 
     # Check requirements
     _check_manifest_requirements(manifest, app_id)
+    _check_services_status_for_app(manifest.get("services", []))
 
     # Check if app can be forked
     instance_number = _installed_instance_number(app_id, last=True) + 1
@@ -2586,6 +2588,31 @@ def unstable_apps():
     return output
 
 
+def _check_services_status_for_app(services):
+
+    logger.debug("Checking that required services are up and running...")
+
+    # Some apps use php-fpm or php5-fpm which is now php7.0-fpm
+    def replace_alias(service):
+        if service in ["php-fpm", "php5-fpm"]:
+            return "php7.0-fpm"
+        else:
+            return service
+    services = [replace_alias(s) for s in services]
+
+    # We only check those, mostly to ignore "custom" services
+    # (added by apps) and because those are the most popular
+    # services
+    service_filter = ["nginx", "php7.0-fpm", "mysql", "postfix"]
+    services = [s for s in services if s in service_filter]
+
+    # List services currently down and raise an exception if any are found
+    faulty_services = [s for s, infos in service_status(services).items() if infos["active"] != "active"]
+    if faulty_services:
+        raise YunohostError('app_action_cannot_be_ran_because_required_services_down',
+                            services=', '.join(faulty_services))
+
+
 def _patch_php5(app_folder):
 
     files_to_patch = []