feat: add multi-language support

README.md

@@ -24,8 +24,9 @@
 **kleinanzeigen-bot** is a console based application to ease publishing of ads to [kleinanzeigen.de](https://kleinanzeigen.de).
 
 It is the spiritual successor to [Second-Hand-Friends/ebayKleinanzeigen](https://github.com/Second-Hand-Friends/ebayKleinanzeigen) with the following advantages:
+- multi-language support (DE/EN)
 - supports Microsoft Edge browser (Chromium based)
-- does not require selenium and chromedrivers
+- does not require Selenium and chromedrivers
 - better captcha handling
 - config:
   - use YAML or JSON for config files

pyproject.toml

@@ -200,6 +200,7 @@ disable= [
     "broad-except",
     "consider-using-assignment-expr",
     "docstring-first-line-empty",
+    "global-statement",
     "missing-docstring",
     "multiple-imports",
     "multiple-statements",
@@ -215,11 +216,13 @@ notes = [ "FIXME", "XXX", "TODO" ] # list of note tags to take in consideration
 [tool.pylint.design]
 # https://pylint.pycqa.org/en/latest/user_guide/configuration/all-options.html#design-checker
 # https://pylint.pycqa.org/en/latest/user_guide/checkers/features.html#design-checker-messages
+max-args       = 6  # maximum number of arguments for function / method (R0913)
 max-attributes = 15 # maximum number of instance attributes for a class (R0902)
 max-branches   = 40 # maximum number of branch for function / method body (R0912)
 max-locals     = 30 # maximum number of local variables for function / method body (R0914)
-max-returns    = 10 # maximum number of return / yield for function / method body (R0911)
+max-returns    = 15 # maximum number of return / yield for function / method body (R0911)
 max-statements = 150 # maximum number of statements in function / method body (R0915)
+max-positional-arguments = 6 # maximum number of positional arguments for function / method (R0917)
 max-public-methods = 30 # maximum number of public methods for a class (R0904)
 
 

src/kleinanzeigen_bot/__init__.py

@@ -9,6 +9,7 @@ import urllib.parse as urllib_parse
 import urllib.request as urllib_request
 from collections.abc import Iterable
 from datetime import datetime
+from gettext import gettext as _
 from logging.handlers import RotatingFileHandler
 from typing import Any, Final
 
@@ -17,14 +18,15 @@ from ruamel.yaml import YAML
 from wcmatch import glob
 
 from . import utils, resources, extract
-from .utils import abspath, ainput, apply_defaults, ensure, is_frozen, pluralize, safe_get, parse_datetime
+from .i18n import Locale, get_current_locale, set_current_locale, get_translating_logger, pluralize
+from .utils import abspath, ainput, apply_defaults, ensure, is_frozen, safe_get, parse_datetime
 from .web_scraping_mixin import By, Element, Page, Is, WebScrapingMixin
 from ._version import __version__
 
 # W0406: possibly a bug, see https://github.com/PyCQA/pylint/issues/3933
 
 LOG_ROOT:Final[logging.Logger] = logging.getLogger()
-LOG:Final[logging.Logger] = logging.getLogger("kleinanzeigen_bot")
+LOG:Final[logging.Logger] = get_translating_logger(__name__)
 LOG.setLevel(logging.INFO)
 
 colorama.init()
@@ -130,7 +132,40 @@ class KleinanzeigenBot(WebScrapingMixin):
         else:
             exe = "python -m kleinanzeigen_bot"
 
-        print(textwrap.dedent(f"""\
+        if get_current_locale().language == "de":
+            print(textwrap.dedent(f"""\
+            Verwendung: {colorama.Fore.LIGHTMAGENTA_EX}{exe} BEFEHL [OPTIONEN]{colorama.Style.RESET_ALL}
+
+            Befehle:
+              publish  - (erneutes) Veröffentlichen von Anzeigen
+              verify   - Überprüft der Konfigurationsdateien
+              delete   - Löscht Anzeigen
+              download - Lädt eine oder mehrere Anzeigen herunter
+              --
+              help     - Zeigt diese Hilfe an (Standardbefehl)
+              version  - Zeigt die Version der Anwendung an
+
+            Optionen:
+              --ads=all|due|new|<id(s)> (publish) - Gibt an, welche Anzeigen (erneut) veröffentlicht werden sollen (STANDARD: due)
+                    Mögliche Werte:
+                    * all: Veröffentlicht alle Anzeigen erneut, ignoriert republication_interval
+                    * due: Veröffentlicht alle neuen Anzeigen und erneut entsprechend dem republication_interval
+                    * new: Veröffentlicht nur neue Anzeigen (d.h. Anzeigen ohne ID in der Konfigurationsdatei)
+                    * <id(s)>: Gibt eine oder mehrere Anzeigen-IDs an, die veröffentlicht werden sollen, z. B. "--ads=1,2,3", ignoriert republication_interval
+              --ads=all|new|<id(s)> (download) - Gibt an, welche Anzeigen heruntergeladen werden sollen (STANDARD: new)
+                    Mögliche Werte:
+                    * all: Lädt alle Anzeigen aus Ihrem Profil herunter
+                    * new: Lädt Anzeigen aus Ihrem Profil herunter, die lokal noch nicht gespeichert sind
+                    * <id(s)>: Gibt eine oder mehrere Anzeigen-IDs zum Herunterladen an, z. B. "--ads=1,2,3"
+              --force           - Alias für '--ads=all'
+              --keep-old        - Verhindert das Löschen alter Anzeigen bei erneuter Veröffentlichung
+              --config=<PATH>   - Pfad zur YAML- oder JSON-Konfigurationsdatei (STANDARD: ./config.yaml)
+              --lang=en|de      - Anzeigesprache (STANDARD: Systemsprache, wenn unterstützt, sonst Englisch)
+              --logfile=<PATH>  - Pfad zur Protokolldatei (STANDARD: ./kleinanzeigen-bot.log)
+              -v, --verbose     - Aktiviert detaillierte Ausgabe – nur nützlich zur Fehlerbehebung
+            """))
+        else:
+            print(textwrap.dedent(f"""\
             Usage: {colorama.Fore.LIGHTMAGENTA_EX}{exe} COMMAND [OPTIONS]{colorama.Style.RESET_ALL}
 
             Commands:
@@ -158,8 +193,9 @@ class KleinanzeigenBot(WebScrapingMixin):
               --keep-old        - don't delete old ads on republication
               --config=<PATH>   - path to the config YAML or JSON file (DEFAULT: ./config.yaml)
               --logfile=<PATH>  - path to the logfile (DEFAULT: ./kleinanzeigen-bot.log)
+              --lang=en|de      - Displaylanguage (STANDARD: Systemlangauge if supported, otherwise English)
               -v, --verbose     - enables verbose output - only useful when troubleshooting issues
-        """))
+            """))
 
     def parse_args(self, args:list[str]) -> None:
         try:
@@ -170,11 +206,12 @@ class KleinanzeigenBot(WebScrapingMixin):
                 "help",
                 "keep-old",
                 "logfile=",
+                "lang=",
                 "verbose"
             ])
         except getopt.error as ex:
             LOG.error(ex.msg)
-            LOG.error("Use --help to display available options")
+            LOG.error("Use --help to display available options.")
             sys.exit(2)
 
         for option, value in options:
@@ -195,6 +232,8 @@ class KleinanzeigenBot(WebScrapingMixin):
                     self.ads_selector = "all"
                 case "--keep-old":
                     self.keep_old_ads = True
+                case "--lang":
+                    set_current_locale(Locale.of(value))
                 case "-v" | "--verbose":
                     LOG.setLevel(logging.DEBUG)
                     logging.getLogger("nodriver").setLevel(logging.INFO)
@@ -244,7 +283,7 @@ class KleinanzeigenBot(WebScrapingMixin):
         if re.compile(r'\d+[,\d+]*').search(self.ads_selector):
             ids = [int(n) for n in self.ads_selector.split(',')]
             use_specific_ads = True
-            LOG.info('Start fetch task for the ad(s) with the id(s):')
+            LOG.info('Start fetch task for the ad(s) with id(s):')
             LOG.info(' | '.join([str(id_) for id_ in ids]))
 
         ad_fields = utils.load_dict_from_module(resources, "ad_fields.yaml")
@@ -261,7 +300,7 @@ class KleinanzeigenBot(WebScrapingMixin):
                 continue
 
             if use_specific_ads:
-                if not ad_cfg["id"] in ids:
+                if ad_cfg["id"] not in ids:
                     LOG.info(" -> SKIPPED: ad [%s] is not in list of given ids.", ad_file)
                     continue
             else:
@@ -362,7 +401,7 @@ class KleinanzeigenBot(WebScrapingMixin):
 
     def load_config(self) -> None:
         config_defaults = utils.load_dict_from_module(resources, "config_defaults.yaml")
-        config = utils.load_dict_if_exists(self.config_file_path, "config")
+        config = utils.load_dict_if_exists(self.config_file_path, _("config"))
 
         if config is None:
             LOG.warning("Config file %s does not exist. Creating it with default values...", self.config_file_path)
@@ -427,7 +466,7 @@ class KleinanzeigenBot(WebScrapingMixin):
         try:
             await self.web_find(By.TEXT, "Wir haben dir gerade einen 6-stelligen Code für die Telefonnummer", timeout = 4)
             LOG.warning("############################################")
-            LOG.warning("# Device verification message detected. Please handle it.")
+            LOG.warning("# Device verification message detected. Please follow the instruction displayed in the Browser.")
             LOG.warning("############################################")
             await ainput("Press ENTER when done...")
         except TimeoutError:
@@ -460,7 +499,7 @@ class KleinanzeigenBot(WebScrapingMixin):
             await self.web_sleep()
 
         LOG.info("############################################")
-        LOG.info("DONE: Deleting %s", pluralize("ad", count))
+        LOG.info("DONE: Deleted %s", pluralize("ad", count))
         LOG.info("############################################")
 
     async def delete_ad(self, ad_cfg: dict[str, Any], delete_old_ads_by_title: bool) -> bool:
@@ -469,8 +508,7 @@ class KleinanzeigenBot(WebScrapingMixin):
         await self.web_open(f"{self.root_url}/m-meine-anzeigen.html")
         csrf_token_elem = await self.web_find(By.CSS_SELECTOR, "meta[name=_csrf]")
         csrf_token = csrf_token_elem.attrs["content"]
-        if csrf_token is None:
+        ensure(csrf_token is not None, "Expected CSRF Token not found in HTML content!")
-            raise AssertionError("Expected CSRF Token not found in HTML content!")
 
         if delete_old_ads_by_title:
             published_ads = json.loads((await self.web_request(f"{self.root_url}/m-meine-anzeigen-verwalten.json?sort=DEFAULT"))["content"])["ads"]
@@ -666,7 +704,7 @@ class KleinanzeigenBot(WebScrapingMixin):
             LOG.warning("# Captcha present! Please solve the captcha.")
             LOG.warning("############################################")
             await self.web_scroll_page_down()
-            input("Press a key to continue...")
+            input(_("Press a key to continue..."))
         except TimeoutError:
             pass
 
@@ -722,7 +760,7 @@ class KleinanzeigenBot(WebScrapingMixin):
             # Click continue button
             await self.web_click(By.XPATH, '//*[contains(@class, "ModalDialog--Actions")]//button[.//*[text()[contains(.,"Bestätigen")]]]')
         except TimeoutError as ex:
-            raise TimeoutError("Unable to close condition dialog") from ex
+            raise TimeoutError(_("Unable to close condition dialog!")) from ex
 
     async def __set_category(self, category: str | None, ad_file:str) -> None:
         # click on something to trigger automatic category detection
@@ -867,10 +905,10 @@ class KleinanzeigenBot(WebScrapingMixin):
         if self.ads_selector in {'all', 'new'}:  # explore ads overview for these two modes
             LOG.info('Scanning your ad overview...')
             own_ad_urls = await ad_extractor.extract_own_ads_urls()
-            LOG.info('%d ads were found!', len(own_ad_urls))
+            LOG.info('%s found.', pluralize("ad", len(own_ad_urls)))
 
             if self.ads_selector == 'all':  # download all of your adds
-                LOG.info('Start fetch task for all your ads!')
+                LOG.info('Starting download of all ads...')
 
                 success_count = 0
                 # call download function for each ad page
@@ -892,7 +930,7 @@ class KleinanzeigenBot(WebScrapingMixin):
                 # determine ad IDs from links
                 ad_id_by_url = {url:ad_extractor.extract_ad_id_from_ad_url(url) for url in own_ad_urls}
 
-                LOG.info('Start fetch task for your unsaved ads!')
+                LOG.info("Starting download of not yet downloaded ads...")
                 new_count = 0
                 for ad_url, ad_id in ad_id_by_url.items():
                     # check if ad with ID already saved
@@ -903,11 +941,11 @@ class KleinanzeigenBot(WebScrapingMixin):
                     if await ad_extractor.naviagte_to_ad_page(ad_url):
                         await ad_extractor.download_ad(ad_id)
                         new_count += 1
-                LOG.info('%d new ad(s) were downloaded from your profile.', new_count)
+                LOG.info('%s were downloaded from your profile.', pluralize("new ad", new_count))
 
         elif re.compile(r'\d+[,\d+]*').search(self.ads_selector):  # download ad(s) with specific id(s)
             ids = [int(n) for n in self.ads_selector.split(',')]
-            LOG.info('Start fetch task for the ad(s) with the id(s):')
+            LOG.info('Starting download of ad(s) with the id(s):')
             LOG.info(' | '.join([str(ad_id) for ad_id in ids]))
 
             for ad_id in ids:  # call download routine for every id
@@ -932,7 +970,7 @@ def main(args:list[str]) -> None:
         |_|\_\_|\___|_|_| |_|\__,_|_| |_/___\___|_|\__, |\___|_| |_|    |_.__/ \___/ \__|
                                                    |___/
                                  https://github.com/Second-Hand-Friends/kleinanzeigen-bot
-        """), flush = True)
+        """)[1:], flush = True)  # [1:] removes the first empty blank line
 
     utils.configure_console_logging()
 

src/kleinanzeigen_bot/extract.py

@@ -9,10 +9,15 @@ import mimetypes
 from datetime import datetime
 from typing import Any, Final
 
+from .i18n import get_translating_logger, pluralize
 from .utils import is_integer, parse_decimal, save_dict
 from .web_scraping_mixin import Browser, By, Element, Is, WebScrapingMixin
 
-LOG:Final[logging.Logger] = logging.getLogger("kleinanzeigen_bot.AdExtractor")
+__all__ = [
+    "AdExtractor",
+]
+
+LOG:Final[logging.Logger] = get_translating_logger(__name__)
 
 
 class AdExtractor(WebScrapingMixin):
@@ -42,7 +47,7 @@ class AdExtractor(WebScrapingMixin):
 
         new_base_dir = os.path.join(relative_directory, f'ad_{ad_id}')
         if os.path.exists(new_base_dir):
-            LOG.info('Deleting current folder of ad...')
+            LOG.info('Deleting current folder of ad %s...', ad_id)
             shutil.rmtree(new_base_dir)
         os.mkdir(new_base_dir)
         LOG.info('New directory for ad created at %s.', new_base_dir)
@@ -68,7 +73,7 @@ class AdExtractor(WebScrapingMixin):
             image_box = await self.web_find(By.CLASS_NAME, 'galleryimage-large')
 
             n_images = len(await self.web_find_all(By.CSS_SELECTOR, '.galleryimage-element[data-ix]', parent = image_box))
-            LOG.info('Found %d images.', n_images)
+            LOG.info('Found %s.', pluralize("image", n_images))
 
             img_element:Element = await self.web_find(By.CSS_SELECTOR, 'div:nth-child(1) > img', parent = image_box)
             img_fn_prefix = 'ad_' + str(ad_id) + '__img'
@@ -97,13 +102,13 @@ class AdExtractor(WebScrapingMixin):
                         new_div = await self.web_find(By.CSS_SELECTOR, f'div.galleryimage-element:nth-child({img_nr + 1})')
                         img_element = await self.web_find(By.TAG_NAME, 'img', parent = new_div)
                     except TimeoutError:
-                        LOG.error('NEXT button in image gallery somehow missing, abort image fetching.')
+                        LOG.error('NEXT button in image gallery somehow missing, aborting image fetching.')
                         break
                 img_nr += 1
-            LOG.info('Downloaded %d image(s).', dl_counter)
+            LOG.info('Downloaded %s.', pluralize("image", dl_counter))
 
         except TimeoutError:  # some ads do not require images
-            LOG.warning('No image area found. Continue without downloading images.')
+            LOG.warning('No image area found. Continuing without downloading images.')
 
         return img_paths
 
@@ -153,10 +158,10 @@ class AdExtractor(WebScrapingMixin):
                 parent = await self.web_find(By.CSS_SELECTOR, 'div:nth-of-type(1)', parent = pagination)))
         if n_buttons > 1:
             multi_page = True
-            LOG.info('It seems like you have many ads!')
+            LOG.info('It looks like you have many ads!')
         else:
             multi_page = False
-            LOG.info('It seems like all your ads fit on one overview page.')
+            LOG.info('It looks like all your ads fit on one overview page.')
 
         refs:list[str] = []
         while True:  # loop reference extraction until no more forward page
@@ -208,7 +213,7 @@ class AdExtractor(WebScrapingMixin):
         # close (warning) popup, if given
         try:
             await self.web_find(By.ID, 'vap-ovrly-secure')
-            LOG.warning('A popup appeared.')
+            LOG.warning('A popup appeared!')
             await self.web_click(By.CLASS_NAME, 'mfp-close')
             await self.web_sleep()
         except TimeoutError:

src/kleinanzeigen_bot/i18n.py

@@ -0,0 +1,206 @@
+"""
+SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
+SPDX-License-Identifier: AGPL-3.0-or-later
+SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
+"""
+import ctypes, gettext, inspect, locale, logging, os, sys
+from collections.abc import Sized
+from typing import Any, Final, NamedTuple
+
+from . import resources, utils  # pylint: disable=cyclic-import
+
+__all__ = [
+    "Locale",
+    "get_translating_logger",
+]
+
+LOG_ROOT:Final[logging.Logger] = logging.getLogger()
+LOG:Final[logging.Logger] = logging.getLogger(__name__)
+
+
+class Locale(NamedTuple):
+
+    language:str  # Language code (e.g., "en", "de")
+    region:str | None = None  # Region code (e.g., "US", "DE")
+    encoding:str = "UTF-8"  # Encoding format (e.g., "UTF-8")
+
+    def __str__(self) -> str:
+        """
+        >>> str(Locale("en", "US", "UTF-8"))
+        'en_US.UTF-8'
+        >>> str(Locale("en", "US"))
+        'en_US.UTF-8'
+        >>> str(Locale("en"))
+        'en.UTF-8'
+        >>> str(Locale("de", None, "UTF-8"))
+        'de.UTF-8'
+        """
+        region_part = f"_{self.region}" if self.region else ""
+        encoding_part = f".{self.encoding}" if self.encoding else ""
+        return f"{self.language}{region_part}{encoding_part}"
+
+    @staticmethod
+    def of(locale_string: str) -> 'Locale':
+        """
+        >>> Locale.of("en_US.UTF-8")
+        Locale(language='en', region='US', encoding='UTF-8')
+        >>> Locale.of("de.UTF-8")
+        Locale(language='de', region=None, encoding='UTF-8')
+        >>> Locale.of("de_DE")
+        Locale(language='de', region='DE', encoding='UTF-8')
+        >>> Locale.of("en")
+        Locale(language='en', region=None, encoding='UTF-8')
+        >>> Locale.of("en.UTF-8")
+        Locale(language='en', region=None, encoding='UTF-8')
+        """
+        parts = locale_string.split(".")
+        language_and_region = parts[0]
+        encoding = parts[1].upper() if len(parts) > 1 else "UTF-8"
+
+        parts = language_and_region.split("_")
+        language = parts[0]
+        region = parts[1].upper() if len(parts) > 1 else None
+
+        return Locale(language = language, region = region, encoding = encoding)
+
+
+def _detect_locale() -> Locale:
+    """
+    Detects the system language, returning a tuple of (language, region, encoding).
+    - On macOS/Linux, it uses the LANG environment variable.
+    - On Windows, it uses the Windows API via ctypes to get the default UI language.
+
+    Returns:
+        (language, region, encoding): e.g. ("en", "US", "UTF-8")
+    """
+    lang = os.environ.get("LANG", None)
+
+    if not lang and os.name == "nt":  # Windows
+        try:
+            lang = locale.windows_locale.get(ctypes.windll.kernel32.GetUserDefaultUILanguage(), "en_US")  # type: ignore[attr-defined,unused-ignore] # mypy
+        except Exception:
+            LOG.warning("Error detecting language on Windows", exc_info = True)
+
+    return Locale.of(lang) if lang else Locale("en", "US", "UTF-8")
+
+
+_CURRENT_LOCALE: Locale = _detect_locale()
+_TRANSLATIONS: dict[str, Any] | None = None
+
+
+def translate(text:object, caller: inspect.FrameInfo | None) -> str:
+    text = str(text)
+    if not caller:
+        return text
+
+    global _TRANSLATIONS
+    if _TRANSLATIONS is None:
+        try:
+            _TRANSLATIONS = utils.load_dict_from_module(resources, f"translations.{_CURRENT_LOCALE[0]}.yaml")
+        except FileNotFoundError:
+            _TRANSLATIONS = {}
+
+    if not _TRANSLATIONS:
+        return text
+
+    module_name = caller.frame.f_globals.get('__name__')  # pylint: disable=redefined-outer-name
+    file_basename = os.path.splitext(os.path.basename(caller.filename))[0]
+    if module_name and module_name.endswith(f".{file_basename}"):
+        module_name = module_name[:-(len(file_basename) + 1)]
+    file_key = f"{file_basename}.py" if module_name == file_basename else f"{module_name}/{file_basename}.py"
+    translation = utils.safe_get(_TRANSLATIONS,
+        file_key,
+        caller.function,
+        text
+    )
+    return translation if translation else text
+
+
+_original_gettext = gettext.gettext
+gettext.gettext = lambda message: translate(_original_gettext(message), utils.get_caller())
+for module_name, module in sys.modules.items():
+    if module is None or module_name in sys.builtin_module_names:
+        continue
+    if hasattr(module, '_') and getattr(module, '_') is _original_gettext:
+        setattr(module, '_', gettext.gettext)
+    if hasattr(module, 'gettext') and getattr(module, 'gettext') is _original_gettext:
+        setattr(module, 'gettext', gettext.gettext)
+
+
+def get_translating_logger(name: str | None = None) -> logging.Logger:
+
+    class TranslatingLogger(logging.Logger):
+
+        def _log(self, level: int, msg: object, *args: Any, **kwargs: Any) -> None:
+            if level != logging.DEBUG:  # debug messages should not be translated
+                msg = translate(msg, utils.get_caller(2))
+            super()._log(level, msg, *args, **kwargs)
+
+    logging.setLoggerClass(TranslatingLogger)
+    return logging.getLogger(name)
+
+
+def get_current_locale() -> Locale:
+    return _CURRENT_LOCALE
+
+
+def set_current_locale(new_locale:Locale) -> None:
+    global _CURRENT_LOCALE, _TRANSLATIONS
+    if new_locale.language != _CURRENT_LOCALE.language:
+        _TRANSLATIONS = None
+    _CURRENT_LOCALE = new_locale
+
+
+def pluralize(noun:str, count:int | Sized, prefix_with_count:bool = True) -> str:
+    """
+    >>> pluralize("field", 1)
+    '1 field'
+    >>> pluralize("field", 2)
+    '2 fields'
+    >>> pluralize("field", 2, prefix_with_count = False)
+    'fields'
+    """
+    noun = translate(noun, utils.get_caller())
+
+    if isinstance(count, Sized):
+        count = len(count)
+
+    prefix = f"{count} " if prefix_with_count else ""
+
+    if count == 1:
+        return f"{prefix}{noun}"
+
+    # German
+    if _CURRENT_LOCALE.language == "de":
+        # Special cases
+        irregular_plurals = {
+            "Attribute": "Attribute",
+            "Bild": "Bilder",
+            "Feld": "Felder",
+        }
+        if noun in irregular_plurals:
+            return f"{prefix}{irregular_plurals[noun]}"
+        for singular_suffix, plural_suffix in irregular_plurals.items():
+            if noun.lower().endswith(singular_suffix):
+                pluralized = noun[:-len(singular_suffix)] + plural_suffix.lower()
+                return f"{prefix}{pluralized}"
+
+        # Very simplified German rules
+        if noun.endswith("ei"):
+            return f"{prefix}{noun}en"  # Datei -> Dateien
+        if noun.endswith("e"):
+            return f"{prefix}{noun}n"  # Blume -> Blumen
+        if noun.endswith(("el", "er", "en")):
+            return f"{prefix}{noun}"  # Keller -> Keller
+        if noun[-1] in "aeiou":
+            return f"{prefix}{noun}s"  # Auto -> Autos
+        return f"{prefix}{noun}e"  # Hund -> Hunde
+
+    # English
+    if len(noun) < 2:
+        return f"{prefix}{noun}s"
+    if noun.endswith(('s', 'sh', 'ch', 'x', 'z')):
+        return f"{prefix}{noun}es"
+    if noun.endswith('y') and noun[-2].lower() not in "aeiou":
+        return f"{prefix}{noun[:-1]}ies"
+    return f"{prefix}{noun}s"

src/kleinanzeigen_bot/resources/translations.de.yaml

@@ -0,0 +1,201 @@
+#################################################
+getopt.py:
+#################################################
+  do_longs:
+    "option --%s requires argument": "Option --%s benötigt ein Argument"
+    "option --%s must not have an argument": "Option --%s darf kein Argument haben"
+  long_has_args:
+    "option --%s not recognized": "Option --%s unbekannt"
+    "option --%s not a unique prefix": "Option --%s ist kein eindeutiger Prefix"
+  do_shorts:
+    "option -%s requires argument": "Option -%s benötigt ein Argument"
+  short_has_arg:
+    "option -%s not recognized": "Option -%s unbekannt"
+
+
+#################################################
+kleinanzeigen_bot/__init__.py:
+#################################################
+  run:
+    "DONE: No configuration errors found.": "FERTIG: Keine Konfigurationsfehler gefunden."
+    'You provided no ads selector. Defaulting to "due".': 'Es wurden keine Anzeigen-Selektor angegeben. Es wird "due" verwendet.'
+    "DONE: No new/outdated ads found.": "FERTIG: Keine neuen/veralteten Anzeigen gefunden."
+    "DONE: No ads to delete found.": "FERTIG: Keine zu löschnenden Anzeigen gefunden."
+    'You provided no ads selector. Defaulting to "new".': 'Es wurden keine Anzeigen-Selektor angegeben. Es wird "new" verwendet.'
+    "Unknown command: %s" : "Unbekannter Befehl: %s"
+
+  show_help:
+    "Usage:": "Verwendung:"
+    "COMMAND [OPTIONS]" : "BEFEHL [OPTIONEN]"
+    "Commands:": "Befehle"
+
+  parse_args:
+    "Use --help to display available options.": "Mit --help können die verfügbaren Optionen angezeigt werden."
+    "More than one command given: %s": "Mehr als ein Befehl angegeben: %s"
+
+  configure_file_logging:
+    "Logging to [%s]...": "Protokollierung in [%s]..."
+    "App version: %s": "App Version: %s"
+    "Python version: %s": "Python Version: %s"
+
+  load_ads:
+    "Searching for ad config files...": "Suche nach Anzeigendateien..."
+    " -> found %s": "-> %s gefunden"
+    "ad config file": "Anzeigendatei"
+    "Start fetch task for the ad(s) with id(s):": "Starte Abrufaufgabe für die Anzeige(n) mit ID(s):"
+    " -> SKIPPED: inactive ad [%s]": " -> ÜBERSPRUNGEN: inaktive Anzeige [%s]"
+    " -> SKIPPED: ad [%s] is not in list of given ids.": " -> ÜBERSPRUNGEN: Anzeige [%s] ist nicht in der Liste der angegebenen IDs."
+    " -> SKIPPED: ad [%s] is not new. already has an id assigned.":
+      " -> ÜBERSPRUNGEN: Anzeige [%s] ist nicht neu. Eine ID wurde bereits zugewiesen."
+    " -> SKIPPED: ad [%s] was last published %d days ago. republication is only required every %s days":
+      " -> ÜBERSPRUNGEN: Anzeige [%s] wurde zuletzt vor %d Tagen veröffentlicht. Eine erneute Veröffentlichung ist nur alle %s Tage erforderlich."
+    "Loaded %s": "%s geladen"
+    "ad": "Anzeige"
+
+  load_config:
+    " -> found %s": "-> %s gefunden"
+    "category": "Kategorie"
+    "config": "Konfiguration"
+
+  login:
+    "Checking if already logged in...": "Überprüfe, ob bereits eingeloggt..."
+    "Already logged in as [%s]. Skipping login.": "Bereits eingeloggt als [%s]. Überspringe Anmeldung."
+    "Opening login page...": "Öffne Anmeldeseite..."
+    "Captcha present! Please solve the captcha.": "Captcha vorhanden! Bitte lösen Sie das Captcha."
+
+  handle_after_login_logic:
+    "# Device verification message detected. Please follow the instruction displayed in the Browser.":
+      "# Nachricht zur Geräteverifizierung erkannt. Bitte den Anweisungen im Browser folgen."
+    "Press ENTER when done...": "EINGABETASTE drücken, wenn erledigt..."
+    "Handling GDPR disclaimer...": "Verarbeite DSGVO-Hinweis..."
+
+  delete_ads:
+    "Processing %s/%s: '%s' from [%s]...": "Verarbeite %s/%s: '%s' von [%s]..."
+    "DONE: Deleted %s": "FERTIG: %s gelöscht"
+    "ad": "Anzeige"
+
+  delete_ad:
+    "Deleting ad '%s' if already present...": "Lösche Anzeige '%s', falls bereits vorhanden..."
+    "Expected CSRF Token not found in HTML content!": "Erwartetes CSRF-Token wurde im HTML-Inhalt nicht gefunden!"
+
+  publish_ads:
+    "Processing %s/%s: '%s' from [%s]...": "Verarbeite %s/%s: '%s' von [%s]..."
+    "DONE: (Re-)published %s": "FERTIG: %s (erneut) veröffentlicht"
+    "ad": "Anzeige"
+
+  publish_ad:
+    "Publishing ad '%s'...": "Veröffentliche Anzeige '%s'..."
+    "Failed to set shipping attribute for type '%s'!": "Fehler beim setzen des Versandattributs für den Typ '%s'!"
+    "# Captcha present! Please solve the captcha.": "# Captcha vorhanden! Bitte lösen Sie das Captcha."
+    "Press a key to continue...": "Eine Taste drücken, um fortzufahren..."
+    " -> SUCCESS: ad published with ID %s": " -> ERFOLG: Anzeige mit ID %s veröffentlicht"
+
+  __set_condition:
+    "Unable to close condition dialog!": "Kann den Dialog für Artikelzustand nicht schließen!"
+
+  __upload_images:
+    " -> found %s": "-> %s gefunden"
+    "image": "Bild"
+    " -> uploading image [%s]": " -> Lade Bild [%s] hoch"
+
+  download_ads:
+    "Scanning your ad overview...": "Scanne Anzeigenübersicht..."
+    '%s found!': '%s gefunden.'
+    "ad": "Anzeige"
+    "Starting download of all ads...": "Starte den Download aller Anzeigen..."
+    '%d of %d ads were downloaded from your profile.': '%d von %d Anzeigen wurden aus Ihrem Profil heruntergeladen.'
+    "Starting download of not yet downloaded ads...": "Starte den Download noch nicht heruntergeladener Anzeigen..."
+    'The ad with id %d has already been saved.': 'Die Anzeige mit der ID %d wurde bereits gespeichert.'
+    '%s were downloaded from your profile.': '%s wurden aus Ihrem Profil heruntergeladen.'
+    "new ad": "neue Anzeige"
+    'Starting download of ad(s) with the id(s):': 'Starte Download der Anzeige(n) mit den ID(s):'
+    'Downloaded ad with id %d': 'Anzeige mit der ID %d heruntergeladen'
+    'The page with the id %d does not exist!': 'Die Seite mit der ID %d existiert nicht!'
+
+
+#################################################
+kleinanzeigen_bot/extract.py:
+#################################################
+  download_ad:
+    "Created ads directory at ./%s.": "Verzeichnis für Anzeigen erstellt unter ./%s."
+    "Deleting current folder of ad %s...": "Lösche aktuellen Ordner der Anzeige %s..."
+    "New directory for ad created at %s.": "Neues Verzeichnis für Anzeige erstellt unter %s."
+
+  _download_images_from_ad_page:
+    "Found %s.": "%s gefunden."
+    "NEXT button in image gallery is missing, aborting image fetching.":
+       "NEXT-Schaltfläche in der Bildergalerie fehlt, Bildabruf abgebrochen."
+    "Downloaded %s.": "%s heruntergeladen."
+    "No image area found. Continue without downloading images.":
+      "Kein Bildbereich gefunden. Fahre fort ohne Bilder herunterzuladen."
+
+  extract_ad_id_from_ad_url:
+    "The ad ID could not be extracted from the given URL %s":
+      "Die Anzeigen-ID konnte nicht aus der angegebenen URL extrahiert werden: %s"
+
+  extract_own_ads_urls:
+    "There are currently no ads on your profile!": "Derzeit gibt es keine Anzeigen auf deinem Profil!"
+    "It looks like you have many ads!": "Es scheint viele Anzeigen zu geben!"
+    "It looks like all your ads fit on one overview page.": "Alle Anzeigen scheinen auf eine Übersichtsseite zu passen."
+    "Last ad overview page explored.": "Letzte Anzeigenübersichtsseite gesichtet."
+
+  naviagte_to_ad_page:
+    "There is no ad under the given ID.": "Es gibt keine Anzeige unter der angegebenen ID."
+    "A popup appeared!": "Ein Popup ist erschienen!"
+
+  _extract_ad_page_info:
+    'Extracting information from ad with title \"%s\"': 'Extrahiere Informationen aus der Anzeige mit dem Titel "%s"'
+
+  _extract_contact_from_ad_page:
+    'No street given in the contact.': 'Keine Straße in den Kontaktdaten angegeben.'
+
+#################################################
+kleinanzeigen_bot/utils.py:
+#################################################
+  format:
+    "ERROR": "FEHLER"
+    "WARNING": "WARNUNG"
+    "CRITICAL": "KRITISCH"
+
+  load_dict_if_exists:
+    "Loading %s[%s]...": "Lade %s[%s]..."
+    " from ": " aus "
+    'Unsupported file type. The file name "%s" must end with *.json, *.yaml, or *.yml':
+      'Nicht unterstützter Dateityp. Der Dateiname "%s" muss mit *.json, *.yaml oder *.yml enden.'
+
+  save_dict:
+    "Saving [%s]...": "Speichere [%s]..."
+
+  on_sigint:
+    "Aborted on user request.": "Auf Benutzerwunsch abgebrochen."
+
+
+#################################################
+kleinanzeigen_bot/web_scraping_mixin.py:
+#################################################
+  create_browser_session:
+    "Creating Browser session...": "Erstelle Browsersitzung..."
+    " -> Browser binary location: %s": " -> Speicherort der Browser-Binärdatei: %s"
+    "Using existing browser process at %s:%s": "Verwende bestehenden Browser-Prozess unter %s:%s"
+    "New Browser session is %s": "Neue Browsersitzung ist %s"
+    " -> Browser profile name: %s": " -> Browser-Profilname: %s"
+    " -> Custom Browser argument: %s": " -> Benutzerdefiniertes Browser-Argument: %s"
+    " -> Browser user data dir: %s": " -> Benutzerdatenverzeichnis des Browsers: %s"
+    " -> Setting chrome prefs [%s]...": " -> Setze Chrome-Einstellungen [%s]..."
+    " -> Adding Browser extension: [%s]": " -> Füge Browser-Erweiterung hinzu: [%s]"
+
+  get_compatible_browser:
+    "Installed browser for OS %s could not be detected": "Installierter Browser für OS %s konnte nicht erkannt werden"
+    "Installed browser could not be detected": "Installierter Browser konnte nicht erkannt werden"
+
+  web_check:
+    "Unsupported attribute: %s": "Nicht unterstütztes Attribut: %s"
+
+  web_find:
+    "Unsupported selector type: %s": "Nicht unterstützter Selektortyp: %s"
+
+  web_find_all:
+    "Unsupported selector type: %s": "Nicht unterstützter Selektortyp: %s"
+
+  web_sleep:
+    " ... pausing for %d ms ...": " ... pausiere für %d ms ..."

src/kleinanzeigen_bot/utils.py

@@ -3,18 +3,20 @@ SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
 SPDX-License-Identifier: AGPL-3.0-or-later
 SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
 """
-import asyncio, copy, decimal, json, logging, os, re, socket, sys, traceback, time
+import asyncio, copy, decimal, inspect, json, logging, os, re, socket, sys, traceback, time
 from importlib.resources import read_text as get_resource_as_string
-from collections.abc import Callable, Sized
+from collections.abc import Callable
 from datetime import datetime
+from gettext import gettext as _
 from types import FrameType, ModuleType, TracebackType
 from typing import Any, Final, TypeVar
 
 import coloredlogs
 from ruamel.yaml import YAML
+from .i18n import get_translating_logger
 
 LOG_ROOT:Final[logging.Logger] = logging.getLogger()
-LOG:Final[logging.Logger] = logging.getLogger("kleinanzeigen_bot.utils")
+LOG:Final[logging.Logger] = get_translating_logger(__name__)
 
 # https://mypy.readthedocs.io/en/stable/generics.html#generic-functions
 T = TypeVar('T')
@@ -45,7 +47,7 @@ def ensure(condition:Any | bool | Callable[[], bool], error_message:str, timeout
     if not isinstance(condition, Callable):  # type: ignore[arg-type] # https://github.com/python/mypy/issues/6864
         if condition:
             return
-        raise AssertionError(error_message)
+        raise AssertionError(_(error_message))
 
     if timeout < 0:
         raise AssertionError("[timeout] must be >= 0")
@@ -56,10 +58,21 @@ def ensure(condition:Any | bool | Callable[[], bool], error_message:str, timeout
     while not condition():  # type: ignore[operator]
         elapsed = time.time() - start_at
         if elapsed >= timeout:
-            raise AssertionError(error_message)
+            raise AssertionError(_(error_message))
         time.sleep(poll_requency)
 
 
+def get_caller(depth: int = 1) -> inspect.FrameInfo | None:
+    stack = inspect.stack()
+    try:
+        for frame in stack[depth + 1:]:
+            if frame.function and frame.function != "<lambda>":
+                return frame
+        return None
+    finally:
+        del stack  # Clean up the stack to avoid reference cycles
+
+
 def is_frozen() -> bool:
     """
     >>> is_frozen()
@@ -140,17 +153,30 @@ def safe_get(a_map:dict[Any, Any], *keys:str) -> Any:
 
 
 def configure_console_logging() -> None:
+
+    class LevelTranslatingFormatter(coloredlogs.ColoredFormatter):  # type: ignore
+
+        def format(self, record:logging.LogRecord) -> str:
+            msg:str = super().format(record)
+            if record.levelno > logging.DEBUG:
+                levelname = _(record.levelname)
+                if levelname != record.levelname:
+                    msg = msg.replace(record.levelname, levelname, 1)
+            return msg
+
+    formatter = LevelTranslatingFormatter("[%(levelname)s] %(message)s")
+
     stdout_log = logging.StreamHandler(sys.stderr)
     stdout_log.setLevel(logging.DEBUG)
-    stdout_log.setFormatter(coloredlogs.ColoredFormatter("[%(levelname)s] %(message)s"))
+    stdout_log.addFilter(type("", (logging.Filter,), {
-    stdout_log.addFilter(type("", (logging.Filter,), {  # pyright: ignore
         "filter": lambda rec: rec.levelno <= logging.INFO
     }))
+    stdout_log.setFormatter(formatter)
     LOG_ROOT.addHandler(stdout_log)
 
     stderr_log = logging.StreamHandler(sys.stderr)
     stderr_log.setLevel(logging.WARNING)
-    stderr_log.setFormatter(coloredlogs.ColoredFormatter("[%(levelname)s] %(message)s"))
+    stderr_log.setFormatter(formatter)
     LOG_ROOT.addHandler(stderr_log)
 
 
@@ -175,29 +201,6 @@ def on_sigint(_sig:int, _frame:FrameType | None) -> None:
     sys.exit(0)
 
 
-def pluralize(noun:str, count:int | Sized, prefix_with_count:bool = True) -> str:
-    """
-    >>> pluralize("field", 1)
-    '1 field'
-    >>> pluralize("field", 2)
-    '2 fields'
-    >>> pluralize("field", 2, prefix_with_count = False)
-    'fields'
-    """
-    if isinstance(count, Sized):
-        count = len(count)
-
-    prefix = f"{count} " if prefix_with_count else ""
-
-    if count == 1:
-        return f"{prefix}{noun}"
-    if noun.endswith('s') or noun.endswith('sh') or noun.endswith('ch') or noun.endswith('x') or noun.endswith('z'):
-        return f"{prefix}{noun}es"
-    if noun.endswith('y'):
-        return f"{prefix}{noun[:-1]}ies"
-    return f"{prefix}{noun}s"
-
-
 def load_dict(filepath:str, content_label:str = "") -> dict[str, Any]:
     """
     :raises FileNotFoundError
@@ -209,12 +212,12 @@ def load_dict(filepath:str, content_label:str = "") -> dict[str, Any]:
 
 
 def load_dict_if_exists(filepath:str, content_label:str = "") -> dict[str, Any] | None:
-    filepath = os.path.abspath(filepath)
+    abs_filepath = os.path.abspath(filepath)
-    LOG.info("Loading %s[%s]...", content_label and content_label + " from " or "", filepath)
+    LOG.info("Loading %s[%s]...", content_label and content_label + _(" from ") or "", abs_filepath)
 
-    _, file_ext = os.path.splitext(filepath)
+    __, file_ext = os.path.splitext(filepath)
-    if file_ext not in [".json", ".yaml", ".yml"]:
+    if file_ext not in (".json", ".yaml", ".yml"):
-        raise ValueError(f'Unsupported file type. The file name "{filepath}" must end with *.json, *.yaml, or *.yml')
+        raise ValueError(_('Unsupported file type. The filename "%s" must end with *.json, *.yaml, or *.yml') % filepath)
 
     if not os.path.exists(filepath):
         return None
@@ -229,9 +232,9 @@ def load_dict_from_module(module:ModuleType, filename:str, content_label:str = "
     """
     LOG.debug("Loading %s[%s.%s]...", content_label and content_label + " from " or "", module.__name__, filename)
 
-    _, file_ext = os.path.splitext(filename)
+    __, file_ext = os.path.splitext(filename)
     if file_ext not in (".json", ".yaml", ".yml"):
-        raise ValueError(f'Unsupported file type. The file name "{filename}" must end with *.json, *.yaml, or *.yml')
+        raise ValueError(f'Unsupported file type. The filename "{filename}" must end with *.json, *.yaml, or *.yml')
 
     content = get_resource_as_string(module, filename)  # pylint: disable=deprecated-method
     return json.loads(content) if filename.endswith(".json") else YAML().load(content)  # type: ignore[no-any-return] # mypy

src/kleinanzeigen_bot/web_scraping_mixin.py

@@ -5,6 +5,7 @@ SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanze
 """
 import asyncio, enum, inspect, json, logging, os, platform, secrets, shutil, time
 from collections.abc import Callable, Coroutine, Iterable
+from gettext import gettext as _
 from typing import cast, Any, Final
 
 try:
@@ -18,12 +19,9 @@ from nodriver.core.config import Config
 from nodriver.core.element import Element
 from nodriver.core.tab import Tab as Page
 
+from .i18n import get_translating_logger
 from .utils import ensure, is_port_open, T
 
-
-LOG:Final[logging.Logger] = logging.getLogger("kleinanzeigen_bot.selenium_mixin")
-
-
 __all__ = [
     "Browser",
     "BrowserConfig",
@@ -31,9 +29,11 @@ __all__ = [
     "Element",
     "Page",
     "Is",
-    "WebScrapingMixin"
+    "WebScrapingMixin",
 ]
 
+LOG:Final[logging.Logger] = get_translating_logger(__name__)
+
 
 class By(enum.Enum):
     ID = enum.auto()
@@ -77,7 +77,7 @@ class WebScrapingMixin:
             ensure(os.path.exists(self.browser_config.binary_location), f"Specified browser binary [{self.browser_config.binary_location}] does not exist.")
         else:
             self.browser_config.binary_location = self.get_compatible_browser()
-        LOG.info(" -> Chrome binary location: %s", self.browser_config.binary_location)
+        LOG.info(" -> Browser binary location: %s", self.browser_config.binary_location)
 
         ########################################################
         # check if an existing browser instance shall be used...
@@ -92,9 +92,9 @@ class WebScrapingMixin:
 
         if remote_port > 0:
             LOG.info("Using existing browser process at %s:%s", remote_host, remote_port)
-            if not is_port_open(remote_host, remote_port):
+            ensure(is_port_open(remote_host, remote_port),
-                raise AssertionError(f"Browser process not reachable at {remote_host}:{remote_port}. "
+                f"Browser process not reachable at {remote_host}:{remote_port}. " +
-                        + f"Start the browser with --remote-debugging-port={remote_port} or remove this port from your config.yaml")
+                f"Start the browser with --remote-debugging-port={remote_port} or remove this port from your config.yaml")
             cfg = Config(
                 browser_executable_path = self.browser_config.binary_location  # actually not necessary but nodriver fails without
             )
@@ -140,7 +140,7 @@ class WebScrapingMixin:
             browser_args.append(f"--profile-directory={self.browser_config.profile_name}")
 
         for browser_arg in self.browser_config.arguments:
-            LOG.info(" -> Custom Chrome argument: %s", browser_arg)
+            LOG.info(" -> Custom Browser argument: %s", browser_arg)
             browser_args.append(browser_arg)
 
         if not LOG.isEnabledFor(logging.DEBUG):
@@ -163,8 +163,8 @@ class WebScrapingMixin:
         os.makedirs(profile_dir, exist_ok = True)
         prefs_file = os.path.join(profile_dir, "Preferences")
         if not os.path.exists(prefs_file):
-            LOG.info("-> Setting chrome prefs [%s]...", prefs_file)
+            LOG.info(" -> Setting chrome prefs [%s]...", prefs_file)
-            with open(prefs_file, "w", encoding='UTF-8') as fd:
+            with open(prefs_file, "w", encoding = 'UTF-8') as fd:
                 json.dump({
                     "credentials_enable_service": False,
                     "enable_do_not_track": True,
@@ -195,7 +195,7 @@ class WebScrapingMixin:
 
         # load extensions
         for crx_extension in self.browser_config.extensions:
-            LOG.info(" -> Adding extension: [%s]", crx_extension)
+            LOG.info(" -> Adding Browser extension: [%s]", crx_extension)
             ensure(os.path.exists(crx_extension), f"Configured extension-file [{crx_extension}] does not exist.")
             cfg.add_extension(crx_extension)
 
@@ -250,15 +250,15 @@ class WebScrapingMixin:
                 ]
 
             case _ as os_name:
-                raise AssertionError(f"Installed browser for OS [{os_name}] could not be detected")
+                raise AssertionError(_("Installed browser for OS %s could not be detected") % os_name)
 
         for browser_path in browser_paths:
             if browser_path and os.path.isfile(browser_path):
                 return browser_path
 
-        raise AssertionError("Installed browser could not be detected")
+        raise AssertionError(_("Installed browser could not be detected"))
 
-    async def web_await(self, condition: Callable[[], T | Never | Coroutine[Any,Any,T | Never]], *,
+    async def web_await(self, condition: Callable[[], T | Never | Coroutine[Any, Any, T | Never]], *,
             timeout:int | float = 5, timeout_error_message: str = "") -> T:
         """
         Blocks/waits until the given condition is met.
@@ -307,6 +307,7 @@ class WebScrapingMixin:
                         && element.offsetHeight > 0
                 }
             """))
+
         elem:Element = await self.web_find(selector_type, selector_value, timeout = timeout)
 
         match attr:
@@ -329,7 +330,7 @@ class WebScrapingMixin:
                         return false
                     }
                 """))
-        raise AssertionError(f"Unsupported attribute: {attr}")
+        raise AssertionError(_("Unsupported attribute: %s") % attr)
 
     async def web_click(self, selector_type:By, selector_value:str, *, timeout:int | float = 5) -> Element:
         """
@@ -380,21 +381,19 @@ class WebScrapingMixin:
                     timeout = timeout,
                     timeout_error_message = f"No HTML element found using CSS selector '{selector_value}' within {timeout} seconds.")
             case By.TEXT:
-                if parent:
+                ensure(not parent, f"Specifying a parent element currently not supported with selector type: {selector_type}")
-                    raise AssertionError(f"Specifying a parent element currently not supported with selector type: {selector_type}")
                 return await self.web_await(
                     lambda: self.page.find_element_by_text(selector_value, True),
                     timeout = timeout,
                     timeout_error_message = f"No HTML element found containing text '{selector_value}' within {timeout} seconds.")
             case By.XPATH:
-                if parent:
+                ensure(not parent, f"Specifying a parent element currently not supported with selector type: {selector_type}")
-                    raise AssertionError(f"Specifying a parent element currently not supported with selector type: {selector_type}")
                 return await self.web_await(
                     lambda: self.page.find_element_by_text(selector_value, True),
                     timeout = timeout,
                     timeout_error_message = f"No HTML element found using XPath '{selector_value}' within {timeout} seconds.")
 
-        raise AssertionError(f"Unsupported selector type: {selector_type}")
+        raise AssertionError(_("Unsupported selector type: %s") % selector_type)
 
     async def web_find_all(self, selector_type:By, selector_value:str, *, parent:Element = None, timeout:int | float = 5) -> list[Element]:
         """
@@ -420,21 +419,19 @@ class WebScrapingMixin:
                     timeout = timeout,
                     timeout_error_message = f"No HTML elements found of tag <{selector_value}> within {timeout} seconds.")
             case By.TEXT:
-                if parent:
+                ensure(not parent, f"Specifying a parent element currently not supported with selector type: {selector_type}")
-                    raise AssertionError(f"Specifying a parent element currently not supported with selector type: {selector_type}")
                 return await self.web_await(
                     lambda: self.page.find_elements_by_text(selector_value),
                     timeout = timeout,
                     timeout_error_message = f"No HTML elements found containing text '{selector_value}' within {timeout} seconds.")
             case By.XPATH:
-                if parent:
+                ensure(not parent, f"Specifying a parent element currently not supported with selector type: {selector_type}")
-                    raise AssertionError(f"Specifying a parent element currently not supported with selector type: {selector_type}")
                 return await self.web_await(
                     lambda: self.page.find_elements_by_text(selector_value),
                     timeout = timeout,
                     timeout_error_message = f"No HTML elements found using XPath '{selector_value}' within {timeout} seconds.")
 
-        raise AssertionError(f"Unsupported selector type: {selector_type}")
+        raise AssertionError(_("Unsupported selector type: %s") % selector_type)
 
     async def web_input(self, selector_type:By, selector_value:str, text:str | int, *, timeout:int | float = 5) -> Element:
         """
@@ -503,7 +500,7 @@ class WebScrapingMixin:
                     content: responseText
                 }}
             }}))
-        """, await_promise=True))
+        """, await_promise = True))
         if isinstance(valid_response_codes, int):
             valid_response_codes = [valid_response_codes]
         ensure(

tests/test_i18n.py

@@ -0,0 +1,58 @@
+"""
+SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
+SPDX-License-Identifier: AGPL-3.0-or-later
+SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
+"""
+import pytest
+from _pytest.monkeypatch import MonkeyPatch  # pylint: disable=import-private-name
+from kleinanzeigen_bot import i18n
+
+
+@pytest.mark.parametrize("lang, expected", [
+    (None, ("en", "US", "UTF-8")),  # Test with no LANG variable (should default to ("en", "US", "UTF-8"))
+    ("fr", ("fr", None, "UTF-8")),  # Test with just a language code
+    ("fr_CA", ("fr", "CA", "UTF-8")),  # Test with language + region, no encoding
+    ("pt_BR.iso8859-1", ("pt", "BR", "ISO8859-1")),  # Test with language + region + encoding
+])
+def test_detect_locale(monkeypatch: MonkeyPatch, lang: str | None, expected: i18n.Locale) -> None:
+    """
+    Pytest test case to verify detect_system_language() behavior under various LANG values.
+    """
+    # Clear or set the LANG environment variable as needed.
+    if lang is None:
+        monkeypatch.delenv("LANG", raising = False)
+    else:
+        monkeypatch.setenv("LANG", lang)
+
+    # Call the function and compare the result to the expected output.
+    result = i18n._detect_locale()  # pylint: disable=protected-access
+    assert result == expected, f"For LANG={lang}, expected {expected} but got {result}"
+
+
+@pytest.mark.parametrize("lang, noun, count, prefix_with_count, expected", [
+    ("en", "field", 1, True, "1 field"),
+    ("en", "field", 2, True, "2 fields"),
+    ("en", "field", 2, False, "fields"),
+    ("en", "attribute", 2, False, "attributes"),
+    ("en", "bus", 2, False, "buses"),
+    ("en", "city", 2, False, "cities"),
+    ("de", "Feld", 1, True, "1 Feld"),
+    ("de", "Feld", 2, True, "2 Felder"),
+    ("de", "Feld", 2, False, "Felder"),
+    ("de", "Anzeige", 2, False, "Anzeigen"),
+    ("de", "Attribute", 2, False, "Attribute"),
+    ("de", "Bild", 2, False, "Bilder"),
+    ("de", "Datei", 2, False, "Dateien"),
+    ("de", "Kategorie", 2, False, "Kategorien")
+])
+def test_pluralize(
+    lang:str,
+    noun:str,
+    count:int,
+    prefix_with_count:bool,
+    expected: str
+) -> None:
+    i18n.set_current_locale(i18n.Locale(lang, "US", "UTF_8"))
+
+    result = i18n.pluralize(noun, count, prefix_with_count)
+    assert result == expected, f"For LANG={lang}, expected {expected} but got {result}"

tests/test_web_scraping_mixin.py

@@ -8,12 +8,13 @@ from typing import cast
 
 import nodriver, pytest
 
-from kleinanzeigen_bot.web_scraping_mixin import WebScrapingMixin
 from kleinanzeigen_bot.utils import ensure
+from kleinanzeigen_bot.i18n import get_translating_logger
+from kleinanzeigen_bot.web_scraping_mixin import WebScrapingMixin
 
 if os.environ.get("CI"):
-    logging.getLogger("kleinanzeigen_bot").setLevel(logging.DEBUG)
+    get_translating_logger("kleinanzeigen_bot").setLevel(logging.DEBUG)
-    logging.getLogger("nodriver").setLevel(logging.DEBUG)
+    get_translating_logger("nodriver").setLevel(logging.DEBUG)
 
 
 async def atest_init() -> None: