Files
changedetection.io/changedetectionio/blueprint/ui/preview.py
dgtlmoon 0674317e14 WIP
2025-12-15 17:29:22 +01:00

132 lines
6.5 KiB
Python

from flask import Blueprint, request, url_for, flash, render_template, redirect
import time
from loguru import logger
from changedetectionio.store import ChangeDetectionStore
from changedetectionio.auth_decorator import login_optionally_required
from changedetectionio import html_tools
def construct_blueprint(datastore: ChangeDetectionStore):
preview_blueprint = Blueprint('ui_preview', __name__, template_folder="../ui/templates")
@preview_blueprint.route("/preview/<string:uuid>", methods=['GET'])
@login_optionally_required
def preview_page(uuid):
"""
Render the preview page for a watch.
This route is processor-aware: it delegates rendering to the processor's
preview.py module, allowing different processor types to provide
custom visualizations:
- text_json_diff: Text preview with syntax highlighting
- image_ssim_diff: Image preview with proper rendering
- restock_diff: Could show latest price/stock data
Each processor implements processors/{type}/preview.py::render()
If a processor doesn't have a preview module, falls back to default text preview.
"""
# More for testing, possible to return the first/only
if uuid == 'first':
uuid = list(datastore.data['watching'].keys()).pop()
try:
watch = datastore.data['watching'][uuid]
except KeyError:
flash("No history found for the specified link, bad link?", "error")
return redirect(url_for('watchlist.index'))
# Get the processor type for this watch
processor_name = watch.get('processor', 'text_json_diff')
try:
# Try to import the processor's preview module
import importlib
processor_module = importlib.import_module(f'changedetectionio.processors.{processor_name}.preview')
# Call the processor's render() function
if hasattr(processor_module, 'render'):
return processor_module.render(
watch=watch,
datastore=datastore,
request=request,
url_for=url_for,
render_template=render_template,
flash=flash,
redirect=redirect
)
except (ImportError, ModuleNotFoundError) as e:
logger.debug(f"Processor {processor_name} does not have a preview module, using default preview: {e}")
# Fallback: if processor doesn't have preview module, use default text preview
content = []
versions = []
timestamp = None
system_uses_webdriver = datastore.data['settings']['application']['fetch_backend'] == 'html_webdriver'
extra_stylesheets = [url_for('static_content', group='styles', filename='diff.css')]
is_html_webdriver = False
if (watch.get('fetch_backend') == 'system' and system_uses_webdriver) or watch.get('fetch_backend') == 'html_webdriver' or watch.get('fetch_backend', '').startswith('extra_browser_'):
is_html_webdriver = True
triggered_line_numbers = []
ignored_line_numbers = []
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")
else:
# So prepare the latest preview or not
preferred_version = request.args.get('version')
versions = list(watch.history.keys())
timestamp = versions[-1]
if preferred_version and preferred_version in versions:
timestamp = preferred_version
try:
versions = list(watch.history.keys())
content = watch.get_history_snapshot(timestamp=timestamp)
triggered_line_numbers = html_tools.strip_ignore_text(content=content,
wordlist=watch.get('trigger_text'),
mode='line numbers'
)
ignored_line_numbers = html_tools.strip_ignore_text(content=content,
wordlist=watch.get('ignore_text'),
mode='line numbers'
)
blocked_line_numbers = html_tools.strip_ignore_text(content=content,
wordlist=watch.get("text_should_not_be_present"),
mode='line numbers'
)
except Exception as e:
content.append({'line': f"File doesnt exist or unable to read timestamp {timestamp}", 'classes': ''})
from changedetectionio.pluggy_interface import get_fetcher_capabilities
capabilities = get_fetcher_capabilities(watch, datastore)
output = render_template("preview.html",
capabilities=capabilities,
content=content,
current_diff_url=watch['url'],
current_version=timestamp,
extra_stylesheets=extra_stylesheets,
extra_title=f" - Diff - {watch.label} @ {timestamp}",
highlight_ignored_line_numbers=ignored_line_numbers,
highlight_triggered_line_numbers=triggered_line_numbers,
highlight_blocked_line_numbers=blocked_line_numbers,
history_n=watch.history_n,
is_html_webdriver=is_html_webdriver,
last_error=watch['last_error'],
last_error_screenshot=watch.get_error_snapshot(),
last_error_text=watch.get_error_text(),
screenshot=watch.get_screenshot(),
uuid=uuid,
versions=versions,
watch=watch,
)
return output
return preview_blueprint