Login message - move to login render, dont duplicate

changedetectionio/blueprint/backups/__init__.py

@@ -3,6 +3,7 @@ import glob
 import threading
 
 from flask import Blueprint, render_template, send_from_directory, flash, url_for, redirect, abort
+from flask_babel import gettext
 import os
 
 from changedetectionio.store import ChangeDetectionStore
@@ -82,11 +83,11 @@ def construct_blueprint(datastore: ChangeDetectionStore):
     @backups_blueprint.route("/request-backup", methods=['GET'])
     def request_backup():
         if any(thread.is_alive() for thread in backup_threads):
-            flash("A backup is already running, check back in a few minutes", "error")
+            flash(gettext("A backup is already running, check back in a few minutes"), "error")
             return redirect(url_for('backups.index'))
 
         if len(find_backups()) > int(os.getenv("MAX_NUMBER_BACKUPS", 100)):
-            flash("Maximum number of backups reached, please remove some", "error")
+            flash(gettext("Maximum number of backups reached, please remove some"), "error")
             return redirect(url_for('backups.index'))
 
         # Be sure we're written fresh
@@ -94,7 +95,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         zip_thread = threading.Thread(target=create_backup, args=(datastore.datastore_path, datastore.data.get("watching")))
         zip_thread.start()
         backup_threads.append(zip_thread)
-        flash("Backup building in background, check back in a few minutes.")
+        flash(gettext("Backup building in background, check back in a few minutes."))
 
         return redirect(url_for('backups.index'))
 
@@ -157,7 +158,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         for backup in backups:
             os.unlink(backup)
 
-        flash("Backups were deleted.")
+        flash(gettext("Backups were deleted."))
 
         return redirect(url_for('backups.index'))
 

changedetectionio/blueprint/imports/importer.py

@@ -2,6 +2,7 @@ from abc import abstractmethod
 import time
 from wtforms import ValidationError
 from loguru import logger
+from flask_babel import gettext
 
 from changedetectionio.forms import validate_url
 
@@ -41,7 +42,7 @@ class import_url_list(Importer):
         now = time.time()
 
         if (len(urls) > 5000):
-            flash("Importing 5,000 of the first URLs from your list, the rest can be imported again.")
+            flash(gettext("Importing 5,000 of the first URLs from your list, the rest can be imported again."))
 
         for url in urls:
             url = url.strip()
@@ -74,7 +75,7 @@ class import_url_list(Importer):
                 self.remaining_data = []
             self.remaining_data.append(url)
 
-        flash("{} Imported from list in {:.2f}s, {} Skipped.".format(good, time.time() - now, len(self.remaining_data)))
+        flash(gettext("{} Imported from list in {:.2f}s, {} Skipped.").format(good, time.time() - now, len(self.remaining_data)))
 
 
 class import_distill_io_json(Importer):
@@ -94,11 +95,11 @@ class import_distill_io_json(Importer):
         try:
             data = json.loads(data.strip())
         except json.decoder.JSONDecodeError:
-            flash("Unable to read JSON file, was it broken?", 'error')
+            flash(gettext("Unable to read JSON file, was it broken?"), 'error')
             return
 
         if not data.get('data'):
-            flash("JSON structure looks invalid, was it broken?", 'error')
+            flash(gettext("JSON structure looks invalid, was it broken?"), 'error')
             return
 
         for d in data.get('data'):
@@ -135,7 +136,7 @@ class import_distill_io_json(Importer):
                     self.new_uuids.append(new_uuid)
                     good += 1
 
-        flash("{} Imported from Distill.io in {:.2f}s, {} Skipped.".format(len(self.new_uuids), time.time() - now, len(self.remaining_data)))
+        flash(gettext("{} Imported from Distill.io in {:.2f}s, {} Skipped.").format(len(self.new_uuids), time.time() - now, len(self.remaining_data)))
 
 
 class import_xlsx_wachete(Importer):
@@ -156,7 +157,7 @@ class import_xlsx_wachete(Importer):
             wb = load_workbook(data)
         except Exception as e:
             # @todo correct except
-            flash("Unable to read export XLSX file, something wrong with the file?", 'error')
+            flash(gettext("Unable to read export XLSX file, something wrong with the file?"), 'error')
             return
 
         row_id = 2
@@ -196,7 +197,7 @@ class import_xlsx_wachete(Importer):
                         validate_url(data.get('url'))
                     except ValidationError as e:
                         logger.error(f">> Import URL error {data.get('url')} {str(e)}")
-                        flash(f"Error processing row number {row_id}, URL value was incorrect, row was skipped.", 'error')
+                        flash(gettext("Error processing row number {}, URL value was incorrect, row was skipped.").format(row_id), 'error')
                         # Don't bother processing anything else on this row
                         continue
 
@@ -210,12 +211,11 @@ class import_xlsx_wachete(Importer):
                         good += 1
             except Exception as e:
                 logger.error(e)
-                flash(f"Error processing row number {row_id}, check all cell data types are correct, row was skipped.", 'error')
+                flash(gettext("Error processing row number {}, check all cell data types are correct, row was skipped.").format(row_id), 'error')
             else:
                 row_id += 1
 
-        flash(
-            "{} imported from Wachete .xlsx in {:.2f}s".format(len(self.new_uuids), time.time() - now))
+        flash(gettext("{} imported from Wachete .xlsx in {:.2f}s").format(len(self.new_uuids), time.time() - now))
 
 
 class import_xlsx_custom(Importer):
@@ -236,7 +236,7 @@ class import_xlsx_custom(Importer):
             wb = load_workbook(data)
         except Exception as e:
             # @todo correct except
-            flash("Unable to read export XLSX file, something wrong with the file?", 'error')
+            flash(gettext("Unable to read export XLSX file, something wrong with the file?"), 'error')
             return
 
         # @todo cehck atleast 2 rows, same in other method
@@ -265,7 +265,7 @@ class import_xlsx_custom(Importer):
                             validate_url(url)
                         except ValidationError as e:
                             logger.error(f">> Import URL error {url} {str(e)}")
-                            flash(f"Error processing row number {row_i}, URL value was incorrect, row was skipped.", 'error')
+                            flash(gettext("Error processing row number {}, URL value was incorrect, row was skipped.").format(row_i), 'error')
                             # Don't bother processing anything else on this row
                             url = None
                             break
@@ -294,9 +294,8 @@ class import_xlsx_custom(Importer):
                         good += 1
         except Exception as e:
             logger.error(e)
-            flash(f"Error processing row number {row_i}, check all cell data types are correct, row was skipped.", 'error')
+            flash(gettext("Error processing row number {}, check all cell data types are correct, row was skipped.").format(row_i), 'error')
         else:
             row_i += 1
 
-        flash(
-            "{} imported from custom .xlsx in {:.2f}s".format(len(self.new_uuids), time.time() - now))
+        flash(gettext("{} imported from custom .xlsx in {:.2f}s").format(len(self.new_uuids), time.time() - now))

changedetectionio/blueprint/settings/__init__.py

@@ -5,6 +5,7 @@ from zoneinfo import ZoneInfo, available_timezones
 import secrets
 import flask_login
 from flask import Blueprint, render_template, request, redirect, url_for, flash
+from flask_babel import gettext
 
 from changedetectionio.store import ChangeDetectionStore
 from changedetectionio.auth_decorator import login_optionally_required
@@ -60,7 +61,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
                 # SALTED_PASS means the password is "locked" to what we set in the Env var
                 if not os.getenv("SALTED_PASS", False):
                     datastore.remove_password()
-                    flash("Password protection removed.", 'notice')
+                    flash(gettext("Password protection removed."), 'notice')
                     flask_login.logout_user()
                     return redirect(url_for('settings.settings_page'))
 
@@ -94,16 +95,16 @@ def construct_blueprint(datastore: ChangeDetectionStore):
                     )
                     
                     if result['status'] == 'success':
-                        flash(f"Worker count adjusted: {result['message']}", 'notice')
+                        flash(gettext("Worker count adjusted: {}").format(result['message']), 'notice')
                     elif result['status'] == 'not_supported':
-                        flash("Dynamic worker adjustment not supported for sync workers", 'warning')
+                        flash(gettext("Dynamic worker adjustment not supported for sync workers"), 'warning')
                     elif result['status'] == 'error':
-                        flash(f"Error adjusting workers: {result['message']}", 'error')
+                        flash(gettext("Error adjusting workers: {}").format(result['message']), 'error')
 
                 if not os.getenv("SALTED_PASS", False) and len(form.application.form.password.encrypted_password):
                     datastore.data['settings']['application']['password'] = form.application.form.password.encrypted_password
                     datastore.needs_write_urgent = True
-                    flash("Password protection enabled.", 'notice')
+                    flash(gettext("Password protection enabled."), 'notice')
                     flask_login.logout_user()
                     return redirect(url_for('watchlist.index'))
 
@@ -122,10 +123,10 @@ def construct_blueprint(datastore: ChangeDetectionStore):
                     if plugin_form.data:
                         save_plugin_settings(datastore.datastore_path, plugin_id, plugin_form.data)
 
-                flash("Settings updated.")
+                flash(gettext("Settings updated."))
 
             else:
-                flash("An error occurred, please see below.", "error")
+                flash(gettext("An error occurred, please see below."), "error")
 
         # Convert to ISO 8601 format, all date/time relative events stored as UTC time
         utc_time = datetime.now(ZoneInfo("UTC")).isoformat()
@@ -175,7 +176,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         secret = secrets.token_hex(16)
         datastore.data['settings']['application']['api_access_token'] = secret
         datastore.needs_write_urgent = True
-        flash("API Key was regenerated.")
+        flash(gettext("API Key was regenerated."))
         return redirect(url_for('settings.settings_page')+'#api')
         
     @settings_blueprint.route("/notification-logs", methods=['GET'])

changedetectionio/blueprint/tags/__init__.py

@@ -1,5 +1,5 @@
 from flask import Blueprint, request, render_template, flash, url_for, redirect
-
+from flask_babel import gettext
 
 from changedetectionio.store import ChangeDetectionStore
 from changedetectionio.flask_app import login_optionally_required
@@ -43,11 +43,11 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         title = request.form.get('name').strip()
 
         if datastore.tag_exists_by_name(title):
-            flash(f'The tag "{title}" already exists', "error")
+            flash(gettext('The tag "{}" already exists').format(title), "error")
             return redirect(url_for('tags.tags_overview_page'))
 
         datastore.add_tag(title)
-        flash("Tag added")
+        flash(gettext("Tag added"))
 
 
         return redirect(url_for('tags.tags_overview_page'))
@@ -72,7 +72,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
                 removed += 1
                 watch['tags'].remove(uuid)
 
-        flash(f"Tag deleted and removed from {removed} watches")
+        flash(gettext("Tag deleted and removed from {} watches").format(removed))
         return redirect(url_for('tags.tags_overview_page'))
 
     @tags_blueprint.route("/unlink/<string:uuid>", methods=['GET'])
@@ -84,7 +84,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
                 unlinked += 1
                 watch['tags'].remove(uuid)
 
-        flash(f"Tag unlinked removed from {unlinked} watches")
+        flash(gettext("Tag unlinked removed from {} watches").format(unlinked))
         return redirect(url_for('tags.tags_overview_page'))
 
     @tags_blueprint.route("/delete_all", methods=['GET'])
@@ -94,7 +94,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
             watch['tags'] = []
         datastore.data['settings']['application']['tags'] = {}
 
-        flash(f"All tags deleted")
+        flash(gettext("All tags deleted"))
         return redirect(url_for('tags.tags_overview_page'))
 
     @tags_blueprint.route("/edit/<string:uuid>", methods=['GET'])
@@ -106,7 +106,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
 
         default = datastore.data['settings']['application']['tags'].get(uuid)
         if not default:
-            flash("Tag not found", "error")
+            flash(gettext("Tag not found"), "error")
             return redirect(url_for('watchlist.index'))
 
         form = group_restock_settings_form(
@@ -181,7 +181,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         datastore.data['settings']['application']['tags'][uuid].update(form.data)
         datastore.data['settings']['application']['tags'][uuid]['processor'] = 'restock_diff'
         datastore.needs_write_urgent = True
-        flash("Updated")
+        flash(gettext("Updated"))
 
         return redirect(url_for('tags.tags_overview_page'))
 

changedetectionio/blueprint/ui/__init__.py

@@ -1,5 +1,6 @@
 import time
 from flask import Blueprint, request, redirect, url_for, flash, render_template, session
+from flask_babel import gettext
 from loguru import logger
 
 from changedetectionio.store import ChangeDetectionStore
@@ -16,42 +17,42 @@ def _handle_operations(op, uuids, datastore, worker_handler, update_q, queuedWat
             if datastore.data['watching'].get(uuid):
                 datastore.delete(uuid)
         if emit_flash:
-            flash(f"{len(uuids)} watches deleted")
+            flash(gettext("{} watches deleted").format(len(uuids)))
 
     elif op == 'pause':
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.data['watching'][uuid]['paused'] = True
         if emit_flash:
-            flash(f"{len(uuids)} watches paused")
+            flash(gettext("{} watches paused").format(len(uuids)))
 
     elif op == 'unpause':
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.data['watching'][uuid.strip()]['paused'] = False
         if emit_flash:
-            flash(f"{len(uuids)} watches unpaused")
+            flash(gettext("{} watches unpaused").format(len(uuids)))
 
     elif (op == 'mark-viewed'):
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.set_last_viewed(uuid, int(time.time()))
         if emit_flash:
-            flash(f"{len(uuids)} watches updated")
+            flash(gettext("{} watches updated").format(len(uuids)))
 
     elif (op == 'mute'):
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.data['watching'][uuid]['notification_muted'] = True
         if emit_flash:
-            flash(f"{len(uuids)} watches muted")
+            flash(gettext("{} watches muted").format(len(uuids)))
 
     elif (op == 'unmute'):
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.data['watching'][uuid]['notification_muted'] = False
         if emit_flash:
-            flash(f"{len(uuids)} watches un-muted")
+            flash(gettext("{} watches un-muted").format(len(uuids)))
 
     elif (op == 'recheck'):
         for uuid in uuids:
@@ -59,21 +60,21 @@ def _handle_operations(op, uuids, datastore, worker_handler, update_q, queuedWat
                 # Recheck and require a full reprocessing
                 worker_handler.queue_item_async_safe(update_q, queuedWatchMetaData.PrioritizedItem(priority=1, item={'uuid': uuid}))
         if emit_flash:
-            flash(f"{len(uuids)} watches queued for rechecking")
+            flash(gettext("{} watches queued for rechecking").format(len(uuids)))
 
     elif (op == 'clear-errors'):
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.data['watching'][uuid]["last_error"] = False
         if emit_flash:
-            flash(f"{len(uuids)} watches errors cleared")
+            flash(gettext("{} watches errors cleared").format(len(uuids)))
 
     elif (op == 'clear-history'):
         for uuid in uuids:
             if datastore.data['watching'].get(uuid):
                 datastore.clear_watch_history(uuid)
         if emit_flash:
-            flash(f"{len(uuids)} watches cleared/reset.")
+            flash(gettext("{} watches cleared/reset.").format(len(uuids)))
 
     elif (op == 'notification-default'):
         from changedetectionio.notification import (
@@ -86,7 +87,7 @@ def _handle_operations(op, uuids, datastore, worker_handler, update_q, queuedWat
                 datastore.data['watching'][uuid]['notification_urls'] = []
                 datastore.data['watching'][uuid]['notification_format'] = USE_SYSTEM_DEFAULT_NOTIFICATION_FORMAT_FOR_WATCH
         if emit_flash:
-            flash(f"{len(uuids)} watches set to use default notification settings")
+            flash(gettext("{} watches set to use default notification settings").format(len(uuids)))
 
     elif (op == 'assign-tag'):
         op_extradata = extra_data
@@ -101,7 +102,7 @@ def _handle_operations(op, uuids, datastore, worker_handler, update_q, queuedWat
 
                         datastore.data['watching'][uuid]['tags'].append(tag_uuid)
         if emit_flash:
-            flash(f"{len(uuids)} watches were tagged")
+            flash(gettext("{} watches were tagged").format(len(uuids)))
 
     if uuids:
         for uuid in uuids:
@@ -138,9 +139,9 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
         try:
             datastore.clear_watch_history(uuid)
         except KeyError:
-            flash('Watch not found', 'error')
+            flash(gettext('Watch not found'), 'error')
         else:
-            flash("Cleared snapshot history for watch {}".format(uuid))
+            flash(gettext("Cleared snapshot history for watch {}").format(uuid))
         return redirect(url_for('watchlist.index'))
 
     @ui_blueprint.route("/clear_history", methods=['GET', 'POST'])
@@ -152,9 +153,9 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
             if confirmtext == 'clear':
                 for uuid in datastore.data['watching'].keys():
                     datastore.clear_watch_history(uuid)
-                flash("Cleared snapshot history for all watches")
+                flash(gettext("Cleared snapshot history for all watches"))
             else:
-                flash('Incorrect confirmation text.', 'error')
+                flash(gettext('Incorrect confirmation text.'), 'error')
 
             return redirect(url_for('watchlist.index'))
 
@@ -188,14 +189,14 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
         uuid = request.args.get('uuid')
 
         if uuid != 'all' and not uuid in datastore.data['watching'].keys():
-            flash('The watch by UUID {} does not exist.'.format(uuid), 'error')
+            flash(gettext('The watch by UUID {} does not exist.').format(uuid), 'error')
             return redirect(url_for('watchlist.index'))
 
         # More for testing, possible to return the first/only
         if uuid == 'first':
             uuid = list(datastore.data['watching'].keys()).pop()
         datastore.delete(uuid)
-        flash('Deleted.')
+        flash(gettext('Deleted.'))
 
         return redirect(url_for('watchlist.index'))
 
@@ -212,7 +213,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
         if not datastore.data['watching'].get(uuid).get('paused'):
             worker_handler.queue_item_async_safe(update_q, queuedWatchMetaData.PrioritizedItem(priority=5, item={'uuid': new_uuid}))
 
-        flash('Cloned, you are editing the new watch.')
+        flash(gettext('Cloned, you are editing the new watch.'))
 
         return redirect(url_for("ui.ui_edit.edit_page", uuid=new_uuid))
 
@@ -251,11 +252,11 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
                         i += 1
 
         if i == 1:
-            flash("Queued 1 watch for rechecking.")
+            flash(gettext("Queued 1 watch for rechecking."))
         if i > 1:
-            flash(f"Queued {i} watches for rechecking.")
+            flash(gettext("Queued {} watches for rechecking.").format(i))
         if i == 0:
-            flash("No watches available to recheck.")
+            flash(gettext("No watches available to recheck."))
 
         return redirect(url_for('watchlist.index', **({'tag': tag} if tag else {})))
 
@@ -326,7 +327,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, worker_handle
 
         except Exception as e:
             logger.error(f"Error sharing -{str(e)}")
-            flash(f"Could not share, something went wrong while communicating with the share server - {str(e)}", 'error')
+            flash(gettext("Could not share, something went wrong while communicating with the share server - {}").format(str(e)), 'error')
 
         return redirect(url_for('watchlist.index'))
 

changedetectionio/blueprint/ui/diff.py

@@ -1,4 +1,5 @@
 from flask import Blueprint, request, redirect, url_for, flash, render_template, make_response, send_from_directory
+from flask_babel import gettext
 
 import re
 import importlib
@@ -89,12 +90,12 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         dates = list(watch.history.keys())
         if not dates or len(dates) < 2:
-            flash("Not enough history (2 snapshots required) to show difference page for this watch.", "error")
+            flash(gettext("Not enough history (2 snapshots required) to show difference page for this watch."), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch
@@ -150,7 +151,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch
@@ -206,7 +207,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch
@@ -273,7 +274,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch

changedetectionio/blueprint/ui/edit.py

@@ -2,6 +2,7 @@ from copy import deepcopy
 import os
 import importlib.resources
 from flask import Blueprint, request, redirect, url_for, flash, render_template, abort
+from flask_babel import gettext
 from loguru import logger
 from jinja2 import Environment, FileSystemLoader
 
@@ -31,14 +32,14 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
 
         # More for testing, possible to return the first/only
         if not datastore.data['watching'].keys():
-            flash("No watches to edit", "error")
+            flash(gettext("No watches to edit"), "error")
             return redirect(url_for('watchlist.index'))
 
         if uuid == 'first':
             uuid = list(datastore.data['watching'].keys()).pop()
 
         if not uuid in datastore.data['watching']:
-            flash("No watch with the UUID %s found." % (uuid), "error")
+            flash(gettext("No watch with the UUID {} found.").format(uuid), "error")
             return redirect(url_for('watchlist.index'))
 
         switch_processor = request.args.get('switch_processor')
@@ -46,7 +47,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
             for p in processors.available_processors():
                 if p[0] == switch_processor:
                     datastore.data['watching'][uuid]['processor'] = switch_processor
-                    flash(f"Switched to mode - {p[1]}.")
+                    flash(gettext("Switched to mode - {}.").format(p[1]))
                     datastore.clear_watch_history(uuid)
                     redirect(url_for('ui_edit.edit_page', uuid=uuid))
 
@@ -65,7 +66,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
         processor_name = datastore.data['watching'][uuid].get('processor', '')
         processor_classes = next((tpl for tpl in processors.find_processors() if tpl[1] == processor_name), None)
         if not processor_classes:
-            flash(f"Cannot load the edit form for processor/plugin '{processor_classes[1]}', plugin missing?", 'error')
+            flash(gettext("Cannot load the edit form for processor/plugin '{}', plugin missing?").format(processor_classes[1]), 'error')
             return redirect(url_for('watchlist.index'))
 
         parent_module = processors.get_parent_module(processor_classes[0])
@@ -235,7 +236,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
             # Recast it if need be to right data Watch handler
             watch_class = processors.get_custom_watch_obj_for_processor(form.data.get('processor'))
             datastore.data['watching'][uuid] = watch_class(datastore_path=datastore.datastore_path, default=datastore.data['watching'][uuid])
-            flash("Updated watch - unpaused!" if request.args.get('unpause_on_save') else "Updated watch.")
+            flash(gettext("Updated watch - unpaused!") if request.args.get('unpause_on_save') else gettext("Updated watch."))
 
             # Re #286 - We wait for syncing new data to disk in another thread every 60 seconds
             # But in the case something is added we should save straight away
@@ -279,7 +280,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
 
         else:
             if request.method == 'POST' and not form.validate():
-                flash("An error occurred, please see below.", "error")
+                flash(gettext("An error occurred, please see below."), "error")
 
             # JQ is difficult to install on windows and must be manually added (outside requirements.txt)
             jq_support = True

changedetectionio/blueprint/ui/preview.py

@@ -1,4 +1,5 @@
 from flask import Blueprint, request, url_for, flash, render_template, redirect
+from flask_babel import gettext
 import time
 from loguru import logger
 
@@ -32,7 +33,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch
@@ -74,7 +75,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         blocked_line_numbers = []
 
         if datastore.data['watching'][uuid].history_n == 0 and (watch.get_error_text() or watch.get_error_snapshot()):
-            flash("Preview unavailable - No fetch/check completed or triggers not reached", "error")
+            flash(gettext("Preview unavailable - No fetch/check completed or triggers not reached"), "error")
         else:
             # So prepare the latest preview or not
             preferred_version = request.args.get('version')
@@ -156,7 +157,7 @@ def construct_blueprint(datastore: ChangeDetectionStore):
         try:
             watch = datastore.data['watching'][uuid]
         except KeyError:
-            flash("No history found for the specified link, bad link?", "error")
+            flash(gettext("No history found for the specified link, bad link?"), "error")
             return redirect(url_for('watchlist.index'))
 
         # Get the processor type for this watch

changedetectionio/blueprint/ui/views.py

@@ -1,4 +1,5 @@
 from flask import Blueprint, request, redirect, url_for, flash
+from flask_babel import gettext
 from changedetectionio.store import ChangeDetectionStore
 from changedetectionio.auth_decorator import login_optionally_required
 from changedetectionio import worker_handler
@@ -20,7 +21,7 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
 
         url = request.form.get('url').strip()
         if datastore.url_exists(url):
-            flash(f'Warning, URL {url} already exists', "notice")
+            flash(gettext('Warning, URL {} already exists').format(url), "notice")
 
         add_paused = request.form.get('edit_and_watch_submit_button') != None
         processor = request.form.get('processor', 'text_json_diff')
@@ -28,12 +29,12 @@ def construct_blueprint(datastore: ChangeDetectionStore, update_q, queuedWatchMe
 
         if new_uuid:
             if add_paused:
-                flash('Watch added in Paused state, saving will unpause.')
+                flash(gettext('Watch added in Paused state, saving will unpause.'))
                 return redirect(url_for('ui.ui_edit.edit_page', uuid=new_uuid, unpause_on_save=1, tag=request.args.get('tag')))
             else:
                 # Straight into the queue.
                 worker_handler.queue_item_async_safe(update_q, queuedWatchMetaData.PrioritizedItem(priority=1, item={'uuid': new_uuid}))
-                flash("Watch added.")
+                flash(gettext("Watch added."))
 
         return redirect(url_for('watchlist.index', tag=request.args.get('tag','')))
 

changedetectionio/flask_app.py

@@ -369,11 +369,11 @@ def changedetection_app(config=None, datastore_o=None):
         # 1. Try to get locale from session (user explicitly selected)
         if 'locale' in session:
             locale = session['locale']
-            print(f"DEBUG: get_locale() returning from session: {locale}")
+            logger.trace(f"DEBUG: get_locale() returning from session: {locale}")
             return locale
         # 2. Fall back to Accept-Language header
         locale = request.accept_languages.best_match(language_codes)
-        print(f"DEBUG: get_locale() returning from Accept-Language: {locale}")
+        logger.trace(f"DEBUG: get_locale() returning from Accept-Language: {locale}")
         return locale
 
     # Initialize Babel with locale selector
@@ -397,6 +397,12 @@ def changedetection_app(config=None, datastore_o=None):
             if request.endpoint and request.endpoint == 'static_content' and request.view_args:
                 # Handled by static_content handler
                 return None
+            # Permitted - static flag icons need to load on login page
+            elif request.endpoint and request.endpoint == 'static_flags':
+                return None
+            # Permitted - language selection should work on login page
+            elif request.endpoint and request.endpoint == 'set_language':
+                return None
             # Permitted
             elif request.endpoint and 'login' in request.endpoint:
                 return None
@@ -465,7 +471,6 @@ def changedetection_app(config=None, datastore_o=None):
 
     @login_manager.unauthorized_handler
     def unauthorized_handler():
-        flash("You must be logged in, please log in.", 'error')
         return redirect(url_for('login', next=url_for('watchlist.index')))
 
     @app.route('/logout')
@@ -492,9 +497,9 @@ def changedetection_app(config=None, datastore_o=None):
 
         if request.method == 'GET':
             if flask_login.current_user.is_authenticated:
-                flash("Already logged in")
+                flash(gettext("Already logged in"))
                 return redirect(url_for("watchlist.index"))
-
+            flash(gettext("You must be logged in, please log in."), 'error')
             output = render_template("login.html")
             return output
 
@@ -519,7 +524,7 @@ def changedetection_app(config=None, datastore_o=None):
             return redirect(url_for('watchlist.index'))
 
         else:
-            flash('Incorrect password', 'error')
+            flash(gettext('Incorrect password'), 'error')
 
         return redirect(url_for('login'))
 

changedetectionio/processors/extract.py

@@ -7,6 +7,7 @@ and exporting to CSV format. This is the default extractor that all processors
 """
 
 import os
+from flask_babel import gettext
 from loguru import logger
 
 
@@ -101,7 +102,7 @@ def process_extraction(watch, datastore, request, url_for, make_response, send_f
         )
 
     if not extract_form.validate():
-        flash("An error occurred, please see below.", "error")
+        flash(gettext("An error occurred, please see below."), "error")
         # render_template needs to be imported from Flask for this to work
         from flask import render_template as flask_render_template
         return render_form(
@@ -127,5 +128,5 @@ def process_extraction(watch, datastore, request, url_for, make_response, send_f
         response.headers['Expires'] = "0"
         return response
 
-    flash('No matches found while scanning all of the watch history for that RegEx.', 'error')
+    flash(gettext('No matches found while scanning all of the watch history for that RegEx.'), 'error')
     return redirect(url_for('ui.ui_diff.diff_history_page_extract_GET', uuid=uuid))

changedetectionio/processors/image_ssim_diff/difference.py

@@ -8,6 +8,7 @@ of concerns and easy backend swapping (LibVIPS, OpenCV, PIL, etc.).
 import os
 import json
 import time
+from flask_babel import gettext
 from loguru import logger
 
 from changedetectionio.processors.image_ssim_diff import SCREENSHOT_COMPARISON_THRESHOLD_OPTIONS_DEFAULT, PROCESSOR_CONFIG_NAME, \
@@ -324,7 +325,7 @@ def render(watch, datastore, request, url_for, render_template, flash, redirect)
     versions = list(watch.history.keys())
 
     if len(versions) < 2:
-        flash("Not enough history to compare. Need at least 2 snapshots.", "error")
+        flash(gettext("Not enough history to compare. Need at least 2 snapshots."), "error")
         return redirect(url_for('watchlist.index'))
 
     # Default: compare latest two versions
@@ -359,7 +360,7 @@ def render(watch, datastore, request, url_for, render_template, flash, redirect)
 
     except Exception as e:
         logger.error(f"Failed to load screenshots: {e}")
-        flash(f"Failed to load screenshots: {e}", "error")
+        flash(gettext("Failed to load screenshots: {}").format(e), "error")
         return redirect(url_for('watchlist.index'))
 
     # Calculate change percentage using isolated subprocess to prevent memory leaks (async-safe)
@@ -408,7 +409,7 @@ def render(watch, datastore, request, url_for, render_template, flash, redirect)
         logger.error(f"Failed to calculate change percentage: {e}")
         import traceback
         logger.error(traceback.format_exc())
-        flash(f"Failed to calculate diff: {e}", "error")
+        flash(gettext("Failed to calculate diff: {}").format(e), "error")
         return redirect(url_for('watchlist.index'))
 
     # Load historical data if available (for charts/visualization)

changedetectionio/processors/image_ssim_diff/preview.py

@@ -4,6 +4,7 @@ Preview rendering for SSIM screenshot processor.
 Renders images properly in the browser instead of showing raw bytes.
 """
 
+from flask_babel import gettext
 from loguru import logger
 
 
@@ -87,7 +88,7 @@ def render(watch, datastore, request, url_for, render_template, flash, redirect)
     versions = list(watch.history.keys())
 
     if len(versions) == 0:
-        flash("Preview unavailable - No snapshots captured yet", "error")
+        flash(gettext("Preview unavailable - No snapshots captured yet"), "error")
         return redirect(url_for('watchlist.index'))
 
     # Get the version to display (default: latest)

changedetectionio/processors/image_ssim_diff/processor.py

@@ -16,8 +16,11 @@ from ..base import difference_detection_processor, SCREENSHOT_FORMAT_PNG
 # All image operations now use OpenCV via isolated_opencv subprocess handler
 # Template matching temporarily disabled pending OpenCV implementation
 
-name = 'Visual / Image screenshot change detection'
-description = 'Compares screenshots using fast OpenCV algorithm, 10-100x faster than SSIM'
+# Translation marker for extraction
+def _(x): return x
+name = _('Visual / Image screenshot change detection')
+description = _('Compares screenshots using fast OpenCV algorithm, 10-100x faster than SSIM')
+del _
 processor_weight = 2
 list_badge_text = "Visual"
 

changedetectionio/processors/restock_diff/processor.py

@@ -8,8 +8,11 @@ import time
 
 urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
 # Translatable strings - extracted by pybabel, translated at runtime in __init__.py
-name = 'Re-stock & Price detection for pages with a SINGLE product'  # _()
-description = 'Detects if the product goes back to in-stock'  # _()
+# Use a marker function so pybabel can extract these strings
+def _(x): return x  # Translation marker for extraction only
+name = _('Re-stock & Price detection for pages with a SINGLE product')
+description = _('Detects if the product goes back to in-stock')
+del _  # Remove marker function
 processor_weight = 1
 list_badge_text = "Restock"  # _()
 

changedetectionio/processors/text_json_diff/processor.py

@@ -17,8 +17,11 @@ from changedetectionio.processors.magic import guess_stream_type
 
 urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
 
-name = 'Webpage Text/HTML, JSON and PDF changes'
-description = 'Detects all text changes where possible'
+# Translation marker for extraction - allows pybabel to find these strings
+def _(x): return x
+name = _('Webpage Text/HTML, JSON and PDF changes')
+description = _('Detects all text changes where possible')
+del _  # Remove marker
 processor_weight = -100
 list_badge_text = "Text"
 

changedetectionio/static/styles/scss/styles.scss

@@ -1171,7 +1171,7 @@ ul#highlightSnippetActions {
   display: flex;
   align-items: center;
   gap: 1rem;
-  padding: 0.75rem 1rem;
+  padding: 0.25rem;
   border-radius: 4px;
   transition: background-color 0.2s ease;
   text-decoration: none;

changedetectionio/store.py

@@ -7,6 +7,7 @@ from changedetectionio.validate_url import is_safe_valid_url
 from flask import (
     flash
 )
+from flask_babel import gettext
 
 from .blueprint.rss import RSS_CONTENT_FORMAT_DEFAULT
 from .html_tools import TRANSLATE_WHITESPACE_TABLE
@@ -382,11 +383,11 @@ class ChangeDetectionStore:
 
             except Exception as e:
                 logger.error(f"Error fetching metadata for shared watch link {url} {str(e)}")
-                flash("Error fetching metadata for {}".format(url), 'error')
+                flash(gettext("Error fetching metadata for {}").format(url), 'error')
                 return False
 
         if not is_safe_valid_url(url):
-            flash('Watch protocol is not permitted or invalid URL format', 'error')
+            flash(gettext('Watch protocol is not permitted or invalid URL format'), 'error')
 
             return None
 

changedetectionio/templates/base.html

@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="en" data-darkmode="{{ get_darkmode_state() }}">
+<html lang="{{ get_locale() }}" data-darkmode="{{ get_darkmode_state() }}">
 
   <head>
     <meta charset="utf-8" >
@@ -266,6 +266,9 @@
           </a>
           {% endfor %}
         </div>
+        <div>
+            {{ _('Language support is in beta, please help us improve by opening a PR on GitHub with any updates.') }}
+        </div>
       </div>
       <div class="modal-footer">
         <button type="button" class="pure-button" id="close-language-modal">{{ _('Cancel') }}</button>

changedetectionio/tests/test_i18n.py

@@ -0,0 +1,112 @@
+#!/usr/bin/env python3
+
+from flask import url_for
+from .util import live_server_setup
+
+
+def test_language_switching(client, live_server, measure_memory_usage, datastore_path):
+    """
+    Test that the language switching functionality works correctly.
+
+    1. Switch to Italian using the /set-language endpoint
+    2. Verify that Italian text appears on the page
+    3. Switch back to English and verify English text appears
+    """
+
+    # Step 1: Set the language to Italian using the /set-language endpoint
+    res = client.get(
+        url_for("set_language", locale="it"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Step 2: Request the index page - should be in Italian
+    # The session cookie should be maintained by the test client
+    res = client.get(
+        url_for("watchlist.index"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Check for Italian text - "Annulla" (translation of "Cancel")
+    assert b"Annulla" in res.data, "Expected Italian text 'Annulla' not found after setting language to Italian"
+
+    assert b'Modifiche testo/HTML, JSON e PDF' in res.data, "Expected italian from processors.available_processors()"
+
+    # Step 3: Switch back to English
+    res = client.get(
+        url_for("set_language", locale="en"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Request the index page - should now be in English
+    res = client.get(
+        url_for("watchlist.index"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Check for English text
+    assert b"Cancel" in res.data, "Expected English text 'Cancel' not found after switching back to English"
+
+
+def test_invalid_locale(client, live_server, measure_memory_usage, datastore_path):
+    """
+    Test that setting an invalid locale doesn't break the application.
+    The app should ignore invalid locales and continue working.
+    """
+
+    # First set to English
+    res = client.get(
+        url_for("set_language", locale="en"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Try to set an invalid locale
+    res = client.get(
+        url_for("set_language", locale="invalid_locale_xyz"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Should still be able to access the page (should stay in English since invalid locale was ignored)
+    res = client.get(
+        url_for("watchlist.index"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+    assert b"Cancel" in res.data, "Should remain in English when invalid locale is provided"
+
+
+def test_language_persistence_in_session(client, live_server, measure_memory_usage, datastore_path):
+    """
+    Test that the language preference persists across multiple requests
+    within the same session.
+    """
+
+    # Set language to Italian
+    res = client.get(
+        url_for("set_language", locale="it"),
+        follow_redirects=True
+    )
+
+    assert res.status_code == 200
+
+    # Make multiple requests - language should persist
+    for _ in range(3):
+        res = client.get(
+            url_for("watchlist.index"),
+            follow_redirects=True
+        )
+
+        assert res.status_code == 200
+        assert b"Annulla" in res.data, "Italian text should persist across requests"