chore: delay some third-party imports

These are not used frequently and delaying makes positive impact on
startup performance and memory usage.

weblate/checks/utils.py

@@ -4,9 +4,6 @@
 
 from operator import itemgetter
 
-from pygments.lexers.markup import RstLexer
-from pygments.token import Token
-
 from weblate.checks.models import CHECKS
 
 
@@ -17,6 +14,9 @@ def highlight_pygments(source: str, unit):
     This is not really a full syntax highlighting, we're only interested in
     non-translatable strings.
     """
+    from pygments.lexers.markup import RstLexer
+    from pygments.token import Token
+
     if "rst-text" in unit.all_flags:
         lexer = RstLexer(stripnl=False)
         start = 0

weblate/fonts/utils.py

@@ -16,7 +16,6 @@
 import gi
 from django.conf import settings
 from django.core.cache import cache as django_cache
-from PIL import ImageFont
 
 from weblate.utils.data import data_dir
 
@@ -259,6 +258,8 @@ def check_render_size(
 
 def get_font_name(filelike):
     """Return tuple of font family and style, for example ('Ubuntu', 'Regular')."""
+    from PIL import ImageFont
+
     if not hasattr(filelike, "loaded_font"):
         # The tempfile creation is workaround for Pillow crashing on invalid font
         # see https://github.com/python-pillow/Pillow/issues/3853

weblate/formats/external.py

@@ -12,9 +12,6 @@
 from zipfile import BadZipFile
 
 from django.utils.translation import gettext_lazy
-from openpyxl import Workbook, load_workbook
-from openpyxl.cell.cell import TYPE_STRING
-from openpyxl.workbook.child import INVALID_TITLE_REGEX
 from translate.storage.csvl10n import csv
 
 from weblate.formats.helpers import CONTROLCHARS_TRANS, NamedBytesIO
@@ -30,13 +27,17 @@ class XlsxFormat(CSVFormat):
     autoload = ("*.xlsx",)
 
     def write_cell(self, worksheet, column: int, row: int, value: str):
+        from openpyxl.cell.cell import TYPE_STRING
+
         cell = worksheet.cell(column=column, row=row)
         cell.value = value
         # Set the data_type after value to override function auto-detection
         cell.data_type = TYPE_STRING
         return cell
 
     def get_title(self, fallback: str = "Weblate"):
+        from openpyxl.workbook.child import INVALID_TITLE_REGEX
+
         title = self.store.targetlanguage
         if title is None:
             return fallback
@@ -47,6 +48,8 @@ def get_title(self, fallback: str = "Weblate"):
         return title
 
     def save_content(self, handle) -> None:
+        from openpyxl import Workbook
+
         workbook = Workbook()
         worksheet = workbook.active
         worksheet.title = self.get_title()
@@ -77,6 +80,8 @@ def serialize(store):
         return output.getvalue()
 
     def parse_store(self, storefile):
+        from openpyxl import load_workbook
+
         # try to load the given file via openpyxl
         # catch at least the BadZipFile exception if an unsupported
         # file has been given

weblate/machinery/aws.py

@@ -2,7 +2,6 @@
 #
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-import boto3
 from django.utils.functional import cached_property
 
 from .base import DownloadTranslations, MachineTranslation
@@ -26,6 +25,8 @@ def get_identifier(cls) -> str:
 
     @cached_property
     def client(self):
+        import boto3
+
         return boto3.client(
             service_name="translate",
             region_name=self.settings["region"],

weblate/machinery/openai.py

@@ -8,11 +8,6 @@
 from typing import TYPE_CHECKING, Literal
 
 from django.core.cache import cache
-from openai import OpenAI
-from openai.types.chat import (
-    ChatCompletionSystemMessageParam,
-    ChatCompletionUserMessageParam,
-)
 
 from weblate.glossary.models import (
     get_glossary_terms,
@@ -66,6 +61,8 @@ class OpenAITranslation(BatchMachineTranslation):
     settings_form = OpenAIMachineryForm
 
     def __init__(self, settings=None) -> None:
+        from openai import OpenAI
+
         super().__init__(settings)
         self.client = OpenAI(api_key=self.settings["key"], timeout=self.request_timeout)
         self._models: None | set[str] = None
@@ -135,6 +132,11 @@ def download_multiple_translations(
         user=None,
         threshold: int = 75,
     ) -> DownloadMultipleTranslations:
+        from openai.types.chat import (
+            ChatCompletionSystemMessageParam,
+            ChatCompletionUserMessageParam,
+        )
+
         texts = [text for text, _unit in sources]
         units = [unit for _text, unit in sources]
         prompt = self.get_prompt(source, language, texts, units)

weblate/screenshots/views.py

@@ -18,8 +18,6 @@
 from django.utils.translation import gettext
 from django.views.decorators.http import require_POST
 from django.views.generic import DetailView, ListView
-from PIL import Image
-from tesserocr import OEM, PSM, RIL, PyTessBaseAPI, iterate_level
 
 from weblate.logger import LOGGER
 from weblate.screenshots.forms import ScreenshotEditForm, ScreenshotForm, SearchForm
@@ -33,6 +31,8 @@
 from weblate.utils.views import PathViewMixin
 
 if TYPE_CHECKING:
+    from tesserocr import PyTessBaseAPI
+
     from weblate.auth.models import AuthenticatedHttpRequest
     from weblate.lang.models import Language
 
@@ -371,6 +371,8 @@ def search_source(request, pk):
 
 
 def ocr_get_strings(api, image: str, resolution: int = 72):
+    from tesserocr import RIL, iterate_level
+
     try:
         api.SetImageFile(image)
     except RuntimeError:
@@ -404,6 +406,8 @@ def ocr_extract(api, image: str, strings, resolution: int):
 
 @contextmanager
 def get_tesseract(language: Language) -> PyTessBaseAPI:
+    from tesserocr import OEM, PSM, PyTessBaseAPI
+
     # Get matching language
     try:
         tess_language = TESSERACT_LANGUAGES[language.code]
@@ -427,6 +431,8 @@ def get_tesseract(language: Language) -> PyTessBaseAPI:
 @login_required
 @require_POST
 def ocr_search(request, pk):
+    from PIL import Image
+
     obj = get_screenshot(request, pk)
     translation = obj.translation
 

weblate/utils/validators.py

@@ -18,7 +18,6 @@
 from django.core.validators import EmailValidator as EmailValidatorDjango
 from django.core.validators import URLValidator, validate_ipv46_address
 from django.utils.translation import gettext, gettext_lazy
-from PIL import Image
 
 from weblate.trans.util import cleanup_path
 from weblate.utils.data import data_dir
@@ -80,6 +79,8 @@ def validate_re_nonempty(value):
 
 def validate_bitmap(value) -> None:
     """Validate bitmap, based on django.forms.fields.ImageField."""
+    from PIL import Image
+
     if value is None:
         return