[improvements][appimage] AppImage updater daemon replaced by a default Python thread to reduce memory usage

CHANGELOG.md

@@ -4,10 +4,12 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
-## [0.7.3]
+## [0.7.3] 2019-
 ### Improvements
 - Not breaking the application when a i18n (translation) key was not found
 - Adding all english (**en**) i18n keys to help people with the application translation
+- AppImage:
+    - AppImage updater daemon replaced by a default Python thread to reduce memory usage
 
 ## [0.7.2] 2019-11-01
 ### Improvements

README.md

@@ -99,7 +99,7 @@ will be pre-downloaded faster ( it does **NOT** modify your **pacman** settings
 - Installed applications are store at **~/.local/share/bauh/appimage/installed**
 - Desktop entries ( menu shortcuts ) of the installed applications are stored at **~/.local/share/applications**
 - Downloaded database files are stored at **~/.local/share/bauh/appimage** as **apps.db** and **releases.db**
-- Databases updater daemon running every 20 minutes. It can be disabled via the environment variable **BAUH_APPIMAGE_DB_UPDATER=0**.
+- Databases updater daemon running every 20 minutes ( the interval in SECONDS can be changed with the environment variable **BAUH_APPIMAGE_DB_UPDATER_TIME** ). It can be disabled via the environment variable **BAUH_APPIMAGE_DB_UPDATER=0**.
 - All supported application names can be found at: https://github.com/vinifmor/bauh-files/blob/master/appimage/apps.txt
 
 Obs: There are some crashes when **AppImageLauncher** is installed. It is advisable to uninstall it and reboot the system before trying to install an AppImage application.

bauh/gems/appimage/controller.py

@@ -7,6 +7,7 @@ import subprocess
 import traceback
 from datetime import datetime
 from pathlib import Path
+from threading import Lock
 from typing import Set, Type, List
 
 from bauh.api.abstract.context import ApplicationContext
@@ -18,7 +19,7 @@ from bauh.api.abstract.view import MessageType
 from bauh.api.constants import HOME_PATH
 from bauh.commons.html import bold
 from bauh.commons.system import SystemProcess, new_subprocess, ProcessHandler, run_cmd, SimpleProcess
-from bauh.gems.appimage import query, INSTALLATION_PATH, suggestions, db
+from bauh.gems.appimage import query, INSTALLATION_PATH, suggestions
 from bauh.gems.appimage.model import AppImage
 from bauh.gems.appimage.worker import DatabaseUpdater
 
@@ -43,18 +44,19 @@ class AppImageManager(SoftwareManager):
         self.http_client = context.http_client
         self.logger = context.logger
         self.file_downloader = context.file_downloader
-        self.dbs_updater = DatabaseUpdater(http_client=context.http_client, logger=context.logger)
+        self.db_locks = {DB_APPS_PATH: Lock(), DB_RELEASES_PATH: Lock()}
+        self.dbs_updater = DatabaseUpdater(http_client=context.http_client, logger=context.logger, db_locks=self.db_locks)
 
     def _get_db_connection(self, db_path: str) -> sqlite3.Connection:
         if os.path.exists(db_path):
-            db.acquire_lock(db_path)
+            self.db_locks[db_path].acquire()
             return sqlite3.connect(db_path)
         else:
             self.logger.warning("Could not get a database connection. File '{}' not found".format(db_path))
 
     def _close_connection(self, db_path: str, con: sqlite3.Connection):
         con.close()
-        db.release_lock(db_path)
+        self.db_locks[db_path].release()
 
     def _gen_app_key(self, app: AppImage):
         return '{}{}'.format(app.name.lower(), app.github.lower() if app.github else '')
@@ -380,9 +382,6 @@ class AppImageManager(SoftwareManager):
         return False
 
     def prepare(self):
-        for path in (DB_APPS_PATH, DB_RELEASES_PATH):
-            db.release_lock(path)
-
         self.dbs_updater.start()
 
     def list_updates(self, internet_available: bool) -> List[PackageUpdate]:

bauh/gems/appimage/db.py

@@ -1,18 +0,0 @@
-import os
-import time
-
-
-def acquire_lock(db_path: str):
-    lock_path = db_path + '.lock'
-    while True:
-        if not os.path.exists(lock_path):
-            open(lock_path, 'a').close()
-            break
-        else:
-            time.sleep(0.0001)
-
-
-def release_lock(db_path: str):
-    lock_path = db_path + '.lock'
-    if os.path.exists(lock_path):
-        os.remove(lock_path)

bauh/gems/appimage/worker.py

@@ -4,27 +4,27 @@ import os
 import tarfile
 import time
 import traceback
-from multiprocessing import Process
 from pathlib import Path
 from threading import Thread
 
 import requests
 
 from bauh.api.http import HttpClient
-from bauh.gems.appimage import LOCAL_PATH, db
+from bauh.gems.appimage import LOCAL_PATH
 
 
-class DatabaseUpdater(Thread if bool(int(os.getenv('BAUH_DEBUG', 0))) else Process):
+class DatabaseUpdater(Thread):
 
     URL_DB = 'https://raw.githubusercontent.com/vinifmor/bauh-files/master/appimage/dbs.tar.gz'
     COMPRESS_FILE_PATH = LOCAL_PATH + '/db.tar.gz'
 
-    def __init__(self, http_client: HttpClient, logger: logging.Logger):
+    def __init__(self, http_client: HttpClient, logger: logging.Logger, db_locks: dict):
         super(DatabaseUpdater, self).__init__(daemon=True)
         self.http_client = http_client
         self.logger = logger
         self.enabled = bool(int(os.getenv('BAUH_APPIMAGE_DB_UPDATER', 1)))
-        self.sleep = 60 * 20
+        self.db_locks = db_locks
+        self.sleep = int(os.getenv('BAUH_APPIMAGE_DB_UPDATER_TIME', 60 * 20))
 
     def _download_databases(self):
         self.logger.info('Retrieving AppImage databases')
@@ -44,9 +44,11 @@ class DatabaseUpdater(Thread if bool(int(os.getenv('BAUH_DEBUG', 0))) else Proce
             if old_db_files:
                 self.logger.info('Deleting old database files')
                 for f in old_db_files:
-                    db.acquire_lock(f)
-                    os.remove(f)
-                    db.release_lock(f)
+                    self.db_locks[f].acquire()
+                    try:
+                        os.remove(f)
+                    finally:
+                        self.db_locks[f].release()
 
                 self.logger.info('Old database files deleted')