Feature/i18n (#174)

* feat: add i18n support

This feature includes the core functions added to /internal, English and Hebrew json files, removal of text strings from the html files, updates to the routes and model updates. Also included are tests. Please note, that this feature is waiting on user registration for final hooks.

* fix(i18n): correct flake8 line length errors

* fix(i18n): attempt to fix build crash at get_translations_dicts() and move foreignkey to last column as requested in CR.

Additional minor doc fixes.

* fix(i18n): simplify check of language file path between live and testing

This change hopefully adds this line to the code coverage.

* fix(i18n): replace glob with path.glob

This change reduces the amount of imports needed and also uses one dir path for both tests and live.

* fix(i18n): revert attempted code improvement

* fix(i18n): added missing language_id to placeholder user

* fix(i18n): added simple test for home

* fix(i18n): code review fixes

* fix(i18n): split the html result dict into two sub-dicts, "variables" and "localized" and the creation of the Jinja2TemplateResponse is now handled in internal/utilities.

* fix(i18n): fixed CR request to not use global state for translations

The translations are now handled with @lru_cache and the function is only re-handled when a new language code parameter is used. This should be the last edit (unless any crash) to this version of the translation feature.

Author: Gonzom

app/babel_mapping.ini

@@ -0,0 +1,8 @@
+# Extraction from Python source files
+
+[python: **.py]
+
+# Extraction from Jinja2 HTML and text templates
+
+[jinja2: **/templates/**.html]
+extensions=jinja2.ext.i18n,jinja2.ext.autoescape,jinja2.ext.with_

app/config.py.example

@@ -27,6 +27,10 @@ MEDIA_DIRECTORY = 'media'
 PICTURE_EXTENSION = '.png'
 AVATAR_SIZE = (120, 120)
 
+
+# DEFAULT WEBSITE LANGUAGE
+WEBSITE_LANGUAGE = "en"
+
 # API-KEYS
 # Get a free API KEY for Astronomy feature @ www.weatherapi.com/signup.aspx
 ASTRONOMY_API_KEY = os.getenv('ASTRONOMY_API_KEY')

app/database/models.py

@@ -42,7 +42,7 @@ class User(Base):
     avatar = Column(String, default="profile.png")
     telegram_id = Column(String, unique=True)
     is_active = Column(Boolean, default=False)
-
+    language_id = Column(Integer, ForeignKey("languages.id"))
     events = relationship("UserEvent", back_populates="participants")
 
     def __repr__(self):
@@ -79,6 +79,13 @@ def __repr__(self):
         return f'<Event {self.id}>'
 
 
+class Language(Base):
+    __tablename__ = "languages"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, unique=True, nullable=False)
+
+
 class Category(Base):
     __tablename__ = "categories"
 

app/dependencies.py

@@ -6,13 +6,13 @@
 from app import config
 from app.internal.logger_customizer import LoggerCustomizer
 
-
 APP_PATH = os.path.dirname(os.path.realpath(__file__))
 MEDIA_PATH = os.path.join(APP_PATH, config.MEDIA_DIRECTORY)
 STATIC_PATH = os.path.join(APP_PATH, "static")
 TEMPLATES_PATH = os.path.join(APP_PATH, "templates")
 
 templates = Jinja2Templates(directory=TEMPLATES_PATH)
+templates.env.add_extension('jinja2.ext.i18n')
 
 # Configure logger
 logger = LoggerCustomizer.make_logger(config.LOG_PATH,

app/internal/languages.py

@@ -0,0 +1,86 @@
+import gettext
+import os
+from pathlib import Path
+from typing import Any, Generator
+
+from app import config
+from app.dependencies import templates
+
+LANGUAGE_DIR = "app/locales"
+LANGUAGE_DIR_TEST = "../app/locales"
+TRANSLATION_FILE = "base"
+
+
+def set_ui_language(language: str = None) -> None:
+    """Set the gettext translations to a given language.
+    If the language requested is not supported, the translations default
+    to the value of config.WEBSITE_LANGUAGE.
+
+    Args:
+        language (str, optional): a valid language code that follows RFC 1766.
+            Defaults to None.
+            See also the Language Code Identifier (LCID) Reference for a list of
+            valid language codes.
+
+    .. _RFC 1766:
+        https://tools.ietf.org/html/rfc1766.html
+
+    .. _Language Code Identifier (LCID) Reference:
+        https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-lcid/a9eac961-e77d-41a6-90a5-ce1a8b0cdb9c # noqa: E501
+    """
+
+    # TODO: Connect when user registration is completed.
+    # if not language:
+    #     language = _get_display_language(user_id: int)
+
+    language_dir = _get_language_directory()
+
+    if language not in list(_get_supported_languages(language_dir)):
+        language = config.WEBSITE_LANGUAGE
+
+    translations = gettext.translation(TRANSLATION_FILE,
+                                       localedir=language_dir,
+                                       languages=[language])
+    translations.install()
+    templates.env.install_gettext_translations(translations, newstyle=True)
+
+
+# TODO: Waiting for user registration. Add doc.
+# def _get_display_language(user_id: int) -> str:
+#     # TODO: handle user language setting:
+#     #  If user is logged in, get language setting.
+#     #  If user is not logged in, get default site setting.
+#
+#     if db_user:
+#         return db_user.language
+#     return config.WEBSITE_LANGUAGE
+
+
+def _get_language_directory() -> str:
+    """Get and return the language directory relative path.
+
+    Returns:
+        str: the language directory relative path.
+    """
+    language_dir = LANGUAGE_DIR
+    if Path(LANGUAGE_DIR_TEST).is_dir():
+        # If running from test, change dir path.
+        language_dir = LANGUAGE_DIR_TEST
+    return language_dir
+
+
+def _get_supported_languages(language_dir: str = _get_language_directory()) \
+        -> Generator[str, Any, None]:
+    """Get and return a generator of supported translation languages codes.
+
+    Args:
+        language_dir (str, optional): the path of the language directory.
+            Defaults to the return value of _get_language_directory().
+
+    Returns:
+        Generator[str, Any, None]: a generator expression of supported
+            translation languages codes.
+    """
+
+    paths = [Path(f.path) for f in os.scandir(language_dir) if f.is_dir()]
+    return (language.name for language in paths)

app/locales/base.pot

@@ -0,0 +1,133 @@
+# Translations template for PROJECT.
+# Copyright (C) 2021 ORGANIZATION
+# This file is distributed under the same license as the PROJECT project.
+# FIRST AUTHOR <EMAIL@ADDRESS>, 2021.
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PROJECT VERSION\n"
+"Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
+"POT-Creation-Date: 2021-02-01 10:21+0200\n"
+"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+"Language-Team: LANGUAGE <LL@li.org>\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=utf-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Generated-By: Babel 2.9.0\n"
+
+#: app/routers/profile.py:19
+msgid "Not found"
+msgstr ""
+
+#: app/templates/agenda.html:11
+msgid "From"
+msgstr ""
+
+#: app/templates/agenda.html:13
+msgid "to"
+msgstr ""
+
+#: app/templates/agenda.html:15
+msgid "Get Agenda"
+msgstr ""
+
+#: app/templates/agenda.html:20
+msgid "Today"
+msgstr ""
+
+#: app/templates/agenda.html:23
+msgid "Next week"
+msgstr ""
+
+#: app/templates/agenda.html:26
+msgid "Next month"
+msgstr ""
+
+#: app/templates/agenda.html:33
+msgid "Start date is greater than end date"
+msgstr ""
+
+#: app/templates/agenda.html:35
+msgid "No events found..."
+msgstr ""
+
+#: app/templates/base.html:18
+msgid "Calendar"
+msgstr ""
+
+#: app/templates/base.html:26
+msgid "Home"
+msgstr ""
+
+#: app/templates/base.html:29
+msgid "Profile"
+msgstr ""
+
+#: app/templates/base.html:32
+msgid "Sign in"
+msgstr ""
+
+#: app/templates/base.html:35
+msgid "Sign up"
+msgstr ""
+
+#: app/templates/base.html:40
+msgid "Agenda"
+msgstr ""
+
+#: app/templates/profile.html:59
+msgid "Update name"
+msgstr ""
+
+#: app/templates/profile.html:66 app/templates/profile.html:88
+#: app/templates/profile.html:109 app/templates/profile.html:133
+msgid "Save changes"
+msgstr ""
+
+#: app/templates/profile.html:80
+msgid "Update email"
+msgstr ""
+
+#: app/templates/profile.html:101
+msgid "Update description"
+msgstr ""
+
+#: app/templates/profile.html:124
+msgid "Update photo"
+msgstr ""
+
+#: app/templates/profile.html:176
+msgid "Settings"
+msgstr ""
+
+#: app/templates/profile.html:207
+msgid "Your feature"
+msgstr ""
+
+#: app/templates/profile.html:228
+msgid "Upcoming event on (date)"
+msgstr ""
+
+#: app/templates/profile.html:239
+msgid "The Event (event)"
+msgstr ""
+
+#: app/templates/profile.html:242
+msgid "Last updated (time) ago"
+msgstr ""
+
+#: app/templates/profile.html:259
+msgid "Explore MeetUps near you"
+msgstr ""
+
+#: app/templates/profile.html:268 app/templates/profile.html:277
+msgid "Your Card"
+msgstr ""
+
+#. i18n: String used in testing. Do not change.
+#: tests/test_language.py:32
+msgid "test python translation"
+msgstr ""
+