from collections import namedtuple from io import BytesIO from random import randint from flask import redirect, url_for, flash, request, make_response, session, Markup, current_app, abort, g, json from flask_login import current_user, login_required from flask_babel import _ from slugify import slugify from sqlalchemy import or_, desc, text from app import db, constants, cache from app.activitypub.signature import RsaKeys, post_request from app.activitypub.util import default_context, notify_about_post, make_image_sizes from app.chat.util import send_message from app.community.forms import SearchRemoteCommunity, CreateDiscussionForm, CreateImageForm, CreateLinkForm, \ ReportCommunityForm, \ DeleteCommunityForm, AddCommunityForm, EditCommunityForm, AddModeratorForm, BanUserCommunityForm, \ EscalateReportForm, ResolveReportForm, CreateVideoForm from app.community.util import search_for_community, community_url_exists, actor_to_community, \ opengraph_parse, url_to_thumbnail_file, save_post, save_icon_file, save_banner_file, send_to_remote_instance, \ delete_post_from_community, delete_post_reply_from_community from app.constants import SUBSCRIPTION_MEMBER, SUBSCRIPTION_OWNER, POST_TYPE_LINK, POST_TYPE_ARTICLE, POST_TYPE_IMAGE, \ SUBSCRIPTION_PENDING, SUBSCRIPTION_MODERATOR, REPORT_STATE_NEW, REPORT_STATE_ESCALATED, REPORT_STATE_RESOLVED, \ REPORT_STATE_DISCARDED, POST_TYPE_VIDEO, NOTIF_COMMUNITY from app.inoculation import inoculation from app.models import User, Community, CommunityMember, CommunityJoinRequest, CommunityBan, Post, \ File, PostVote, utcnow, Report, Notification, InstanceBlock, ActivityPubLog, Topic, Conversation, PostReply, \ NotificationSubscription from app.community import bp from app.user.utils import search_for_user from app.utils import get_setting, render_template, allowlist_html, markdown_to_html, validation_required, \ shorten_string, gibberish, community_membership, ap_datetime, \ request_etag_matches, return_304, instance_banned, can_create_post, can_upvote, can_downvote, user_filters_posts, \ joined_communities, moderating_communities, blocked_domains, mimetype_from_url, blocked_instances, \ community_moderators, communities_banned_from, show_ban_message, recently_upvoted_posts, recently_downvoted_posts, \ blocked_users from feedgen.feed import FeedGenerator from datetime import timezone, timedelta @bp.route('/add_local', methods=['GET', 'POST']) @login_required def add_local(): if current_user.banned: return show_ban_message() flash('PieFed is still being tested so hosting communities on piefed.social is not advised except for testing purposes.', 'warning') form = AddCommunityForm() if g.site.enable_nsfw is False: form.nsfw.render_kw = {'disabled': True} if form.validate_on_submit() and not community_url_exists(form.url.data): # todo: more intense data validation if form.url.data.strip().lower().startswith('/c/'): form.url.data = form.url.data[3:] form.url.data = slugify(form.url.data.strip(), separator='_') private_key, public_key = RsaKeys.generate_keypair() community = Community(title=form.community_name.data, name=form.url.data, description=form.description.data, rules=form.rules.data, nsfw=form.nsfw.data, private_key=private_key, public_key=public_key, description_html=markdown_to_html(form.description.data), rules_html=markdown_to_html(form.rules.data), local_only=form.local_only.data, ap_profile_id='https://' + current_app.config['SERVER_NAME'] + '/c/' + form.url.data.lower(), ap_public_url='https://' + current_app.config['SERVER_NAME'] + '/c/' + form.url.data, ap_followers_url='https://' + current_app.config['SERVER_NAME'] + '/c/' + form.url.data + '/followers', ap_domain=current_app.config['SERVER_NAME'], subscriptions_count=1, instance_id=1, low_quality='memes' in form.url.data) icon_file = request.files['icon_file'] if icon_file and icon_file.filename != '': file = save_icon_file(icon_file) if file: community.icon = file banner_file = request.files['banner_file'] if banner_file and banner_file.filename != '': file = save_banner_file(banner_file) if file: community.image = file db.session.add(community) db.session.commit() membership = CommunityMember(user_id=current_user.id, community_id=community.id, is_moderator=True, is_owner=True) db.session.add(membership) db.session.commit() flash(_('Your new community has been created.')) cache.delete_memoized(community_membership, current_user, community) cache.delete_memoized(joined_communities, current_user.id) cache.delete_memoized(moderating_communities, current_user.id) return redirect('/c/' + community.name) return render_template('community/add_local.html', title=_('Create community'), form=form, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()), current_app=current_app) @bp.route('/add_remote', methods=['GET', 'POST']) @login_required def add_remote(): if current_user.banned: return show_ban_message() form = SearchRemoteCommunity() new_community = None if form.validate_on_submit(): address = form.address.data.strip().lower() if address.startswith('!') and '@' in address: new_community = search_for_community(address) elif address.startswith('@') and '@' in address[1:]: # todo: the user is searching for a person instead ... elif '@' in address: new_community = search_for_community('!' + address) else: message = Markup( 'Type address in the format !community@server.name. Search on Lemmyverse.net to find some.') flash(message, 'error') if new_community is None: if g.site.enable_nsfw: flash(_('Community not found.'), 'warning') else: flash(_('Community not found. If you are searching for a nsfw community it is blocked by this instance.'), 'warning') else: if new_community.banned: flash(_('That community is banned from %(site)s.', site=g.site.name), 'warning') return render_template('community/add_remote.html', title=_('Add remote community'), form=form, new_community=new_community, subscribed=community_membership(current_user, new_community) >= SUBSCRIPTION_MEMBER, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id())) # @bp.route('/c/', methods=['GET']) - defined in activitypub/routes.py, which calls this function for user requests. A bit weird. def show_community(community: Community): if community.banned: abort(404) page = request.args.get('page', 1, type=int) sort = request.args.get('sort', '' if current_user.is_anonymous else current_user.default_sort) if sort is None: sort = '' low_bandwidth = request.cookies.get('low_bandwidth', '0') == '1' if low_bandwidth: post_layout = None else: if community.default_layout is not None: post_layout = request.args.get('layout', community.default_layout) else: post_layout = request.args.get('layout', 'list') # If nothing has changed since their last visit, return HTTP 304 current_etag = f"{community.id}{sort}{post_layout}_{hash(community.last_active)}" if current_user.is_anonymous and request_etag_matches(current_etag): return return_304(current_etag) mods = community_moderators(community.id) is_moderator = current_user.is_authenticated and any(mod.user_id == current_user.id for mod in mods) is_owner = current_user.is_authenticated and any( mod.user_id == current_user.id and mod.is_owner == True for mod in mods) is_admin = current_user.is_authenticated and current_user.is_admin() if community.private_mods: mod_list = [] else: mod_user_ids = [mod.user_id for mod in mods] mod_list = User.query.filter(User.id.in_(mod_user_ids)).all() posts = community.posts # filter out nsfw and nsfl if desired if current_user.is_anonymous: posts = posts.filter(Post.from_bot == False, Post.nsfw == False, Post.nsfl == False) content_filters = {} else: if current_user.ignore_bots: posts = posts.filter(Post.from_bot == False) if current_user.show_nsfl is False: posts = posts.filter(Post.nsfl == False) if current_user.show_nsfw is False: posts = posts.filter(Post.nsfw == False) content_filters = user_filters_posts(current_user.id) # filter domains and instances domains_ids = blocked_domains(current_user.id) if domains_ids: posts = posts.filter(or_(Post.domain_id.not_in(domains_ids), Post.domain_id == None)) instance_ids = blocked_instances(current_user.id) if instance_ids: posts = posts.filter(or_(Post.instance_id.not_in(instance_ids), Post.instance_id == None)) # filter blocked users blocked_accounts = blocked_users(current_user.id) if blocked_accounts: posts = posts.filter(Post.user_id.not_in(blocked_accounts)) if sort == '' or sort == 'hot': posts = posts.order_by(desc(Post.sticky)).order_by(desc(Post.ranking)).order_by(desc(Post.posted_at)) elif sort == 'top': posts = posts.filter(Post.posted_at > utcnow() - timedelta(days=7)).order_by(desc(Post.sticky)).order_by(desc(Post.up_votes - Post.down_votes)) elif sort == 'new': posts = posts.order_by(desc(Post.posted_at)) elif sort == 'active': posts = posts.order_by(desc(Post.sticky)).order_by(desc(Post.last_active)) per_page = 100 if post_layout == 'masonry': per_page = 200 elif post_layout == 'masonry_wide': per_page = 300 posts = posts.paginate(page=page, per_page=per_page, error_out=False) breadcrumbs = [] breadcrumb = namedtuple("Breadcrumb", ['text', 'url']) breadcrumb.text = _('Home') breadcrumb.url = '/' breadcrumbs.append(breadcrumb) if community.topic_id: related_communities = Community.query.filter_by(topic_id=community.topic_id).\ filter(Community.id != community.id, Community.banned == False).order_by(Community.name) topics = [] previous_topic = Topic.query.get(community.topic_id) topics.append(previous_topic) while previous_topic.parent_id: topic = Topic.query.get(previous_topic.parent_id) topics.append(topic) previous_topic = topic topics = list(reversed(topics)) breadcrumb = namedtuple("Breadcrumb", ['text', 'url']) breadcrumb.text = _('Topics') breadcrumb.url = '/topics' breadcrumbs.append(breadcrumb) existing_url = '/topic' for topic in topics: breadcrumb = namedtuple("Breadcrumb", ['text', 'url']) breadcrumb.text = topic.name breadcrumb.url = f"{existing_url}/{topic.machine_name}" breadcrumbs.append(breadcrumb) existing_url = breadcrumb.url else: related_communities = [] breadcrumb = namedtuple("Breadcrumb", ['text', 'url']) breadcrumb.text = _('Communities') breadcrumb.url = '/communities' breadcrumbs.append(breadcrumb) description = shorten_string(community.description, 150) if community.description else None og_image = community.image.source_url if community.image_id else None next_url = url_for('activitypub.community_profile', actor=community.ap_id if community.ap_id is not None else community.name, page=posts.next_num, sort=sort, layout=post_layout) if posts.has_next else None prev_url = url_for('activitypub.community_profile', actor=community.ap_id if community.ap_id is not None else community.name, page=posts.prev_num, sort=sort, layout=post_layout) if posts.has_prev and page != 1 else None # Voting history if current_user.is_authenticated: recently_upvoted = recently_upvoted_posts(current_user.id) recently_downvoted = recently_downvoted_posts(current_user.id) else: recently_upvoted = [] recently_downvoted = [] return render_template('community/community.html', community=community, title=community.title, breadcrumbs=breadcrumbs, is_moderator=is_moderator, is_owner=is_owner, is_admin=is_admin, mods=mod_list, posts=posts, description=description, og_image=og_image, POST_TYPE_IMAGE=POST_TYPE_IMAGE, POST_TYPE_LINK=POST_TYPE_LINK, POST_TYPE_VIDEO=POST_TYPE_VIDEO, SUBSCRIPTION_PENDING=SUBSCRIPTION_PENDING, SUBSCRIPTION_MEMBER=SUBSCRIPTION_MEMBER, SUBSCRIPTION_OWNER=SUBSCRIPTION_OWNER, SUBSCRIPTION_MODERATOR=SUBSCRIPTION_MODERATOR, etag=f"{community.id}{sort}{post_layout}_{hash(community.last_active)}", related_communities=related_communities, next_url=next_url, prev_url=prev_url, low_bandwidth=low_bandwidth, recently_upvoted=recently_upvoted, recently_downvoted=recently_downvoted, rss_feed=f"https://{current_app.config['SERVER_NAME']}/community/{community.link()}/feed", rss_feed_name=f"{community.title} on PieFed", content_filters=content_filters, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()), sort=sort, inoculation=inoculation[randint(0, len(inoculation) - 1)], post_layout=post_layout, current_app=current_app) # RSS feed of the community @bp.route('//feed', methods=['GET']) @cache.cached(timeout=600) def show_community_rss(actor): actor = actor.strip() if '@' in actor: community: Community = Community.query.filter_by(ap_id=actor, banned=False).first() else: community: Community = Community.query.filter_by(name=actor, banned=False, ap_id=None).first() if community is not None: # If nothing has changed since their last visit, return HTTP 304 current_etag = f"{community.id}_{hash(community.last_active)}" if request_etag_matches(current_etag): return return_304(current_etag, 'application/rss+xml') posts = community.posts.filter(Post.from_bot == False).order_by(desc(Post.created_at)).limit(100).all() description = shorten_string(community.description, 150) if community.description else None og_image = community.image.source_url if community.image_id else None fg = FeedGenerator() fg.id(f"https://{current_app.config['SERVER_NAME']}/c/{actor}") fg.title(f'{community.title} on {g.site.name}') fg.link(href=f"https://{current_app.config['SERVER_NAME']}/c/{actor}", rel='alternate') if og_image: fg.logo(og_image) else: fg.logo(f"https://{current_app.config['SERVER_NAME']}/static/images/apple-touch-icon.png") if description: fg.subtitle(description) else: fg.subtitle(' ') fg.link(href=f"https://{current_app.config['SERVER_NAME']}/c/{actor}/feed", rel='self') fg.language('en') for post in posts: fe = fg.add_entry() fe.title(post.title) fe.link(href=f"https://{current_app.config['SERVER_NAME']}/post/{post.id}") if post.url: type = mimetype_from_url(post.url) if type and not type.startswith('text/'): fe.enclosure(post.url, type=type) fe.description(post.body_html) fe.guid(post.profile_id(), permalink=True) fe.author(name=post.author.user_name) fe.pubDate(post.created_at.replace(tzinfo=timezone.utc)) response = make_response(fg.rss_str()) response.headers.set('Content-Type', 'application/rss+xml') response.headers.add_header('ETag', f"{community.id}_{hash(community.last_active)}") response.headers.add_header('Cache-Control', 'no-cache, max-age=600, must-revalidate') return response else: abort(404) @bp.route('//subscribe', methods=['GET']) @login_required @validation_required def subscribe(actor): remote = False actor = actor.strip() if '@' in actor: community = Community.query.filter_by(banned=False, ap_id=actor).first() remote = True else: community = Community.query.filter_by(name=actor, banned=False, ap_id=None).first() if community is not None: if community_membership(current_user, community) != SUBSCRIPTION_MEMBER and community_membership(current_user, community) != SUBSCRIPTION_PENDING: banned = CommunityBan.query.filter_by(user_id=current_user.id, community_id=community.id).first() if banned: flash(_('You cannot join this community')) if remote: # send ActivityPub message to remote community, asking to follow. Accept message will be sent to our shared inbox join_request = CommunityJoinRequest(user_id=current_user.id, community_id=community.id) db.session.add(join_request) db.session.commit() follow = { "actor": f"https://{current_app.config['SERVER_NAME']}/u/{current_user.user_name}", "to": [community.ap_profile_id], "object": community.ap_profile_id, "type": "Follow", "id": f"https://{current_app.config['SERVER_NAME']}/activities/follow/{join_request.id}" } success = post_request(community.ap_inbox_url, follow, current_user.private_key, current_user.profile_id() + '#main-key') if not success: flash(_("There was a problem while trying to communicate with remote server. If other people have already joined this community it won't matter."), 'error') # for local communities, joining is instant member = CommunityMember(user_id=current_user.id, community_id=community.id) db.session.add(member) db.session.commit() flash('You joined ' + community.title) referrer = request.headers.get('Referer', None) cache.delete_memoized(community_membership, current_user, community) cache.delete_memoized(joined_communities, current_user.id) if referrer is not None: return redirect(referrer) else: return redirect('/c/' + actor) else: abort(404) @bp.route('//unsubscribe', methods=['GET']) @login_required def unsubscribe(actor): community = actor_to_community(actor) if community is not None: subscription = community_membership(current_user, community) if subscription: if subscription != SUBSCRIPTION_OWNER: proceed = True # Undo the Follow if '@' in actor: # this is a remote community, so activitypub is needed undo_id = f"https://{current_app.config['SERVER_NAME']}/activities/undo/" + gibberish(15) follow = { "actor": f"https://{current_app.config['SERVER_NAME']}/u/{current_user.user_name}", "to": [community.ap_profile_id], "object": community.ap_profile_id, "type": "Follow", "id": f"https://{current_app.config['SERVER_NAME']}/activities/follow/{gibberish(15)}" } undo = { 'actor': current_user.profile_id(), 'to': [community.ap_profile_id], 'type': 'Undo', 'id': undo_id, 'object': follow } success = post_request(community.ap_inbox_url, undo, current_user.private_key, current_user.profile_id() + '#main-key') if not success: flash('There was a problem while trying to unsubscribe', 'error') if proceed: db.session.query(CommunityMember).filter_by(user_id=current_user.id, community_id=community.id).delete() db.session.query(CommunityJoinRequest).filter_by(user_id=current_user.id, community_id=community.id).delete() db.session.commit() flash('You have left ' + community.title) cache.delete_memoized(community_membership, current_user, community) cache.delete_memoized(joined_communities, current_user.id) else: # todo: community deletion flash('You need to make someone else the owner before unsubscribing.', 'warning') # send them back where they came from referrer = request.headers.get('Referer', None) if referrer is not None: return redirect(referrer) else: return redirect('/c/' + actor) else: abort(404) @bp.route('//join_then_add', methods=['GET', 'POST']) @login_required @validation_required def join_then_add(actor): community = actor_to_community(actor) if not current_user.subscribed(community.id): if not community.is_local(): # send ActivityPub message to remote community, asking to follow. Accept message will be sent to our shared inbox join_request = CommunityJoinRequest(user_id=current_user.id, community_id=community.id) db.session.add(join_request) db.session.commit() follow = { "actor": f"https://{current_app.config['SERVER_NAME']}/u/{current_user.user_name}", "to": [community.ap_profile_id], "object": community.ap_profile_id, "type": "Follow", "id": f"https://{current_app.config['SERVER_NAME']}/activities/follow/{join_request.id}" } success = post_request(community.ap_inbox_url, follow, current_user.private_key, current_user.profile_id() + '#main-key') member = CommunityMember(user_id=current_user.id, community_id=community.id) db.session.add(member) db.session.commit() flash('You joined ' + community.title) if not community.user_is_banned(current_user): return redirect(url_for('community.add_discussion_post', actor=community.link())) else: abort(401) @bp.route('//submit', methods=['GET', 'POST']) @login_required @validation_required def add_discussion_post(actor): if current_user.banned: return show_ban_message() community = actor_to_community(actor) form = CreateDiscussionForm() if g.site.enable_nsfl is False: form.nsfl.render_kw = {'disabled': True} if community.nsfw: form.nsfw.data = True form.nsfw.render_kw = {'disabled': True} if community.nsfl: form.nsfl.data = True form.nsfw.render_kw = {'disabled': True} if not(community.is_moderator() or community.is_owner() or current_user.is_admin()): form.sticky.render_kw = {'disabled': True} form.communities.choices = [(c.id, c.display_name()) for c in current_user.communities()] if not can_create_post(current_user, community): abort(401) if form.validate_on_submit(): community = Community.query.get_or_404(form.communities.data) if not can_create_post(current_user, community): abort(401) post = Post(user_id=current_user.id, community_id=form.communities.data, instance_id=1) save_post(form, post, 'discussion') community.post_count += 1 community.last_active = g.site.last_active = utcnow() db.session.commit() post.ap_id = f"https://{current_app.config['SERVER_NAME']}/post/{post.id}" db.session.commit() notify_about_post(post) if not community.local_only: federate_post(community, post) return redirect(f"/post/{post.id}") else: form.communities.data = community.id form.notify_author.data = True if community.posting_warning: flash(community.posting_warning) return render_template('community/add_discussion_post.html', title=_('Add post to community'), form=form, community=community, markdown_editor=current_user.markdown_editor, low_bandwidth=False, actor=actor, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.id), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) @bp.route('//submit_image', methods=['GET', 'POST']) @login_required @validation_required def add_image_post(actor): if current_user.banned: return show_ban_message() community = actor_to_community(actor) form = CreateImageForm() if g.site.enable_nsfl is False: form.nsfl.render_kw = {'disabled': True} if community.nsfw: form.nsfw.data = True form.nsfw.render_kw = {'disabled': True} if community.nsfl: form.nsfl.data = True form.nsfw.render_kw = {'disabled': True} if not(community.is_moderator() or community.is_owner() or current_user.is_admin()): form.sticky.render_kw = {'disabled': True} form.communities.choices = [(c.id, c.display_name()) for c in current_user.communities()] if not can_create_post(current_user, community): abort(401) if form.validate_on_submit(): community = Community.query.get_or_404(form.communities.data) if not can_create_post(current_user, community): abort(401) post = Post(user_id=current_user.id, community_id=form.communities.data, instance_id=1) save_post(form, post, 'image') community.post_count += 1 community.last_active = g.site.last_active = utcnow() db.session.commit() post.ap_id = f"https://{current_app.config['SERVER_NAME']}/post/{post.id}" db.session.commit() if post.image_id and post.image.file_path is None: make_image_sizes(post.image_id, 150, 512, 'posts') # the 512 sized image is for masonry view # Update list of cross posts if post.url: other_posts = Post.query.filter(Post.id != post.id, Post.url == post.url, Post.posted_at > post.posted_at - timedelta(days=6)).all() for op in other_posts: if op.cross_posts is None: op.cross_posts = [post.id] else: op.cross_posts.append(post.id) if post.cross_posts is None: post.cross_posts = [op.id] else: post.cross_posts.append(op.id) db.session.commit() notify_about_post(post) if not community.local_only: federate_post(community, post) return redirect(f"/post/{post.id}") else: form.communities.data = community.id form.notify_author.data = True return render_template('community/add_image_post.html', title=_('Add post to community'), form=form, community=community, markdown_editor=current_user.markdown_editor, low_bandwidth=False, actor=actor, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.id), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) @bp.route('//submit_link', methods=['GET', 'POST']) @login_required @validation_required def add_link_post(actor): if current_user.banned: return show_ban_message() community = actor_to_community(actor) form = CreateLinkForm() if g.site.enable_nsfl is False: form.nsfl.render_kw = {'disabled': True} if community.nsfw: form.nsfw.data = True form.nsfw.render_kw = {'disabled': True} if community.nsfl: form.nsfl.data = True form.nsfw.render_kw = {'disabled': True} if not(community.is_moderator() or community.is_owner() or current_user.is_admin()): form.sticky.render_kw = {'disabled': True} form.communities.choices = [(c.id, c.display_name()) for c in current_user.communities()] if not can_create_post(current_user, community): abort(401) if form.validate_on_submit(): community = Community.query.get_or_404(form.communities.data) if not can_create_post(current_user, community): abort(401) post = Post(user_id=current_user.id, community_id=form.communities.data, instance_id=1) save_post(form, post, 'link') community.post_count += 1 community.last_active = g.site.last_active = utcnow() db.session.commit() post.ap_id = f"https://{current_app.config['SERVER_NAME']}/post/{post.id}" db.session.commit() if post.image_id and post.image.file_path is None: make_image_sizes(post.image_id, 150, 512, 'posts') # the 512 sized image is for masonry view # Update list of cross posts if post.url: other_posts = Post.query.filter(Post.id != post.id, Post.url == post.url, Post.posted_at > post.posted_at - timedelta(days=6)).all() for op in other_posts: if op.cross_posts is None: op.cross_posts = [post.id] else: op.cross_posts.append(post.id) if post.cross_posts is None: post.cross_posts = [op.id] else: post.cross_posts.append(op.id) db.session.commit() notify_about_post(post) if not community.local_only: federate_post(community, post) return redirect(f"/post/{post.id}") else: form.communities.data = community.id form.notify_author.data = True return render_template('community/add_link_post.html', title=_('Add post to community'), form=form, community=community, markdown_editor=current_user.markdown_editor, low_bandwidth=False, actor=actor, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.id), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) @bp.route('//submit_video', methods=['GET', 'POST']) @login_required @validation_required def add_video_post(actor): if current_user.banned: return show_ban_message() community = actor_to_community(actor) form = CreateVideoForm() if g.site.enable_nsfl is False: form.nsfl.render_kw = {'disabled': True} if community.nsfw: form.nsfw.data = True form.nsfw.render_kw = {'disabled': True} if community.nsfl: form.nsfl.data = True form.nsfw.render_kw = {'disabled': True} if not(community.is_moderator() or community.is_owner() or current_user.is_admin()): form.sticky.render_kw = {'disabled': True} form.communities.choices = [(c.id, c.display_name()) for c in current_user.communities()] if not can_create_post(current_user, community): abort(401) if form.validate_on_submit(): community = Community.query.get_or_404(form.communities.data) if not can_create_post(current_user, community): abort(401) post = Post(user_id=current_user.id, community_id=form.communities.data, instance_id=1) save_post(form, post, 'video') community.post_count += 1 community.last_active = g.site.last_active = utcnow() db.session.commit() post.ap_id = f"https://{current_app.config['SERVER_NAME']}/post/{post.id}" db.session.commit() if post.image_id and post.image.file_path is None: make_image_sizes(post.image_id, 150, 512, 'posts') # the 512 sized image is for masonry view # Update list of cross posts if post.url: other_posts = Post.query.filter(Post.id != post.id, Post.url == post.url, Post.posted_at > post.posted_at - timedelta(days=6)).all() for op in other_posts: if op.cross_posts is None: op.cross_posts = [post.id] else: op.cross_posts.append(post.id) if post.cross_posts is None: post.cross_posts = [op.id] else: post.cross_posts.append(op.id) db.session.commit() notify_about_post(post) if not community.local_only: federate_post(community, post) return redirect(f"/post/{post.id}") else: form.communities.data = community.id form.notify_author.data = True return render_template('community/add_video_post.html', title=_('Add post to community'), form=form, community=community, markdown_editor=current_user.markdown_editor, low_bandwidth=False, actor=actor, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.id), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) def federate_post(community, post): page = { 'type': 'Page', 'id': post.ap_id, 'attributedTo': current_user.ap_profile_id, 'to': [ community.ap_profile_id, 'https://www.w3.org/ns/activitystreams#Public' ], 'name': post.title, 'cc': [], 'content': post.body_html if post.body_html else '', 'mediaType': 'text/html', 'source': { 'content': post.body if post.body else '', 'mediaType': 'text/markdown' }, 'attachment': [], 'commentsEnabled': post.comments_enabled, 'sensitive': post.nsfw, 'nsfl': post.nsfl, 'stickied': post.sticky, 'published': ap_datetime(utcnow()), 'audience': community.ap_profile_id } create = { "id": f"https://{current_app.config['SERVER_NAME']}/activities/create/{gibberish(15)}", "actor": current_user.ap_profile_id, "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "cc": [ community.ap_profile_id ], "type": "Create", "audience": community.ap_profile_id, "object": page, '@context': default_context() } if post.type == POST_TYPE_LINK or post.type == POST_TYPE_VIDEO: page['attachment'] = [{'href': post.url, 'type': 'Link'}] elif post.image_id: image_url = '' if post.image.source_url: image_url = post.image.source_url elif post.image.file_path: image_url = post.image.file_path.replace('app/static/', f"https://{current_app.config['SERVER_NAME']}/static/") elif post.image.thumbnail_path: image_url = post.image.thumbnail_path.replace('app/static/', f"https://{current_app.config['SERVER_NAME']}/static/") # NB image is a dict while attachment is a list of dicts (usually just one dict in the list) page['image'] = {'type': 'Image', 'url': image_url} if post.type == POST_TYPE_IMAGE: page['attachment'] = [{'type': 'Link', 'href': post.image.source_url}] # source_url is always a https link, no need for .replace() as done above if not community.is_local(): # this is a remote community - send the post to the instance that hosts it success = post_request(community.ap_inbox_url, create, current_user.private_key, current_user.ap_profile_id + '#main-key') if success: flash(_('Your post to %(name)s has been made.', name=community.title)) else: flash('There was a problem making your post to ' + community.title) else: # local community - send (announce) post out to followers announce = { "id": f"https://{current_app.config['SERVER_NAME']}/activities/announce/{gibberish(15)}", "type": 'Announce', "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "actor": community.ap_profile_id, "cc": [ community.ap_followers_url ], '@context': default_context(), 'object': create } sent_to = 0 for instance in community.following_instances(): if instance.inbox and not current_user.has_blocked_instance(instance.id) and not instance_banned( instance.domain): send_to_remote_instance(instance.id, community.id, announce) sent_to += 1 if sent_to: flash(_('Your post to %(name)s has been made.', name=community.title)) else: flash(_('Your post to %(name)s has been made.', name=community.title)) @bp.route('/community//report', methods=['GET', 'POST']) @login_required def community_report(community_id: int): community = Community.query.get_or_404(community_id) form = ReportCommunityForm() if form.validate_on_submit(): report = Report(reasons=form.reasons_to_string(form.reasons.data), description=form.description.data, type=1, reporter_id=current_user.id, suspect_community_id=community.id, source_instance_id=1) db.session.add(report) # Notify admin # todo: find all instance admin(s). for now just load User.id == 1 admins = [User.query.get_or_404(1)] for admin in admins: notification = Notification(user_id=admin.id, title=_('A community has been reported'), url=community.local_url(), author_id=current_user.id) db.session.add(notification) admin.unread_notifications += 1 db.session.commit() # todo: federate report to originating instance if not community.is_local() and form.report_remote.data: ... flash(_('Community has been reported, thank you!')) return redirect(community.local_url()) return render_template('community/community_report.html', title=_('Report community'), form=form, community=community) @bp.route('/community//edit', methods=['GET', 'POST']) @login_required def community_edit(community_id: int): from app.admin.util import topics_for_form if current_user.banned: return show_ban_message() community = Community.query.get_or_404(community_id) if community.is_owner() or current_user.is_admin(): form = EditCommunityForm() form.topic.choices = topics_for_form(0) if form.validate_on_submit(): community.title = form.title.data community.description = form.description.data community.description_html = markdown_to_html(form.description.data) community.rules = form.rules.data community.rules_html = markdown_to_html(form.rules.data) community.nsfw = form.nsfw.data community.local_only = form.local_only.data community.restricted_to_mods = form.restricted_to_mods.data community.new_mods_wanted = form.new_mods_wanted.data community.topic_id = form.topic.data if form.topic.data != 0 else None community.default_layout = form.default_layout.data icon_file = request.files['icon_file'] if icon_file and icon_file.filename != '': if community.icon_id: community.icon.delete_from_disk() file = save_icon_file(icon_file) if file: community.icon = file banner_file = request.files['banner_file'] if banner_file and banner_file.filename != '': if community.image_id: community.image.delete_from_disk() file = save_banner_file(banner_file) if file: community.image = file db.session.commit() if community.topic: community.topic.num_communities = community.topic.communities.count() db.session.commit() flash(_('Saved')) return redirect(url_for('activitypub.community_profile', actor=community.ap_id if community.ap_id is not None else community.name)) else: form.title.data = community.title form.description.data = community.description form.rules.data = community.rules form.nsfw.data = community.nsfw form.local_only.data = community.local_only form.new_mods_wanted.data = community.new_mods_wanted form.restricted_to_mods.data = community.restricted_to_mods form.topic.data = community.topic_id if community.topic_id else None form.default_layout.data = community.default_layout return render_template('community/community_edit.html', title=_('Edit community'), form=form, current_app=current_app, current="edit_settings", community=community, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id())) else: abort(401) @bp.route('/community//delete', methods=['GET', 'POST']) @login_required def community_delete(community_id: int): if current_user.banned: return show_ban_message() community = Community.query.get_or_404(community_id) if community.is_owner() or current_user.is_admin(): form = DeleteCommunityForm() if form.validate_on_submit(): if community.is_local(): community.banned = True # todo: federate deletion out to all instances. At end of federation process, delete_dependencies() and delete community community.delete_dependencies() db.session.delete(community) db.session.commit() flash(_('Community deleted')) return redirect('/communities') return render_template('community/community_delete.html', title=_('Delete community'), form=form, community=community, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id())) else: abort(401) @bp.route('/community//moderators', methods=['GET', 'POST']) @login_required def community_mod_list(community_id: int): if current_user.banned: return show_ban_message() community = Community.query.get_or_404(community_id) if community.is_owner() or current_user.is_admin(): moderators = User.query.filter(User.banned == False).join(CommunityMember, CommunityMember.user_id == User.id).\ filter(CommunityMember.community_id == community_id, or_(CommunityMember.is_moderator == True, CommunityMember.is_owner == True)).all() return render_template('community/community_mod_list.html', title=_('Moderators for %(community)s', community=community.display_name()), moderators=moderators, community=community, current="moderators", moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()) ) @bp.route('/community//moderators/add', methods=['GET', 'POST']) @login_required def community_add_moderator(community_id: int): if current_user.banned: return show_ban_message() community = Community.query.get_or_404(community_id) if community.is_owner() or current_user.is_admin(): form = AddModeratorForm() if form.validate_on_submit(): new_moderator = search_for_user(form.user_name.data) if new_moderator: existing_member = CommunityMember.query.filter(CommunityMember.user_id == new_moderator.id, CommunityMember.community_id == community_id).first() if existing_member: existing_member.is_moderator = True else: new_member = CommunityMember(community_id=community_id, user_id=new_moderator.id, is_moderator=True) db.session.add(new_member) db.session.commit() flash(_('Moderator added')) # Notify new mod if new_moderator.is_local(): notify = Notification(title=_('You are now a moderator of %(name)s', name=community.display_name()), url='/c/' + community.name, user_id=new_moderator.id, author_id=current_user.id) new_moderator.unread_notifications += 1 db.session.add(notify) db.session.commit() else: # for remote users, send a chat message to let them know existing_conversation = Conversation.find_existing_conversation(recipient=new_moderator, sender=current_user) if not existing_conversation: existing_conversation = Conversation(user_id=current_user.id) existing_conversation.members.append(new_moderator) existing_conversation.members.append(current_user) db.session.add(existing_conversation) db.session.commit() server = current_app.config['SERVER_NAME'] send_message(f"Hi there. I've added you as a moderator to the community !{community.name}@{server}.", existing_conversation.id) # Flush cache cache.delete_memoized(moderating_communities, new_moderator.id) cache.delete_memoized(joined_communities, new_moderator.id) cache.delete_memoized(community_moderators, community_id) return redirect(url_for('community.community_mod_list', community_id=community.id)) else: flash(_('Account not found'), 'warning') return render_template('community/community_add_moderator.html', title=_('Add moderator to %(community)s', community=community.display_name()), community=community, form=form, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()) ) @bp.route('/community//moderators/remove/', methods=['GET', 'POST']) @login_required def community_remove_moderator(community_id: int, user_id: int): if current_user.banned: return show_ban_message() community = Community.query.get_or_404(community_id) if community.is_owner() or current_user.is_admin(): existing_member = CommunityMember.query.filter(CommunityMember.user_id == user_id, CommunityMember.community_id == community_id).first() if existing_member: existing_member.is_moderator = False db.session.commit() flash(_('Moderator removed')) # Flush cache cache.delete_memoized(moderating_communities, user_id) cache.delete_memoized(joined_communities, user_id) cache.delete_memoized(community_moderators, community_id) return redirect(url_for('community.community_mod_list', community_id=community.id)) @bp.route('/community//block_instance', methods=['GET', 'POST']) @login_required def community_block_instance(community_id: int): community = Community.query.get_or_404(community_id) existing = InstanceBlock.query.filter_by(user_id=current_user.id, instance_id=community.instance_id).first() if not existing: db.session.add(InstanceBlock(user_id=current_user.id, instance_id=community.instance_id)) db.session.commit() flash(_('Content from %(name)s will be hidden.', name=community.instance.domain)) return redirect(community.local_url()) @bp.route('/community///ban_user_community', methods=['GET', 'POST']) @login_required def community_ban_user(community_id: int, user_id: int): community = Community.query.get_or_404(community_id) user = User.query.get_or_404(user_id) existing = CommunityBan.query.filter_by(community_id=community.id, user_id=user.id).first() form = BanUserCommunityForm() if form.validate_on_submit(): # Both CommunityBan and CommunityMember need to be updated. CommunityBan is under the control of moderators while # CommunityMember can be cleared by the user by leaving the group and rejoining. CommunityMember.is_banned stops # posts from the community from showing up in the banned person's home feed. if not existing: new_ban = CommunityBan(community_id=community_id, user_id=user.id, banned_by=current_user.id, reason=form.reason.data) if form.ban_until.data is not None and form.ban_until.data < utcnow().date(): new_ban.ban_until = form.ban_until.data db.session.add(new_ban) db.session.commit() community_membership_record = CommunityMember.query.filter_by(community_id=community.id, user_id=user.id).first() if community_membership_record: community_membership_record.is_banned = True db.session.commit() flash(_('%(name)s has been banned.', name=user.display_name())) if form.delete_posts.data: posts = Post.query.filter(Post.user_id == user.id, Post.community_id == community.id).all() for post in posts: delete_post_from_community(post.id) if posts: flash(_('Posts by %(name)s have been deleted.', name=user.display_name())) if form.delete_post_replies.data: post_replies = PostReply.query.filter(PostReply.user_id == user.id, Post.community_id == community.id).all() for post_reply in post_replies: delete_post_reply_from_community(post_reply.id) if post_replies: flash(_('Comments by %(name)s have been deleted.', name=user.display_name())) # todo: federate ban to post author instance # Notify banned person if user.is_local(): cache.delete_memoized(communities_banned_from, user.id) cache.delete_memoized(joined_communities, user.id) cache.delete_memoized(moderating_communities, user.id) notify = Notification(title=shorten_string('You have been banned from ' + community.title), url=f'/notifications', user_id=user.id, author_id=1) db.session.add(notify) user.unread_notifications += 1 db.session.commit() else: ... # todo: send chatmessage to remote user and federate it # Remove their notification subscription, if any db.session.query(NotificationSubscription).filter(NotificationSubscription.entity_id == community.id, NotificationSubscription.user_id == user.id, NotificationSubscription.type == NOTIF_COMMUNITY).delete() return redirect(community.local_url()) else: return render_template('community/community_ban_user.html', title=_('Ban from community'), form=form, community=community, user=user, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) @bp.route('/community///unban_user_community', methods=['GET', 'POST']) @login_required def community_unban_user(community_id: int, user_id: int): community = Community.query.get_or_404(community_id) user = User.query.get_or_404(user_id) existing_ban = CommunityBan.query.filter_by(community_id=community.id, user_id=user.id).first() if existing_ban: db.session.delete(existing_ban) db.session.commit() community_membership_record = CommunityMember.query.filter_by(community_id=community.id, user_id=user.id).first() if community_membership_record: community_membership_record.is_banned = False db.session.commit() flash(_('%(name)s has been unbanned.', name=user.display_name())) # todo: federate ban to post author instance # notify banned person if user.is_local(): cache.delete_memoized(communities_banned_from, user.id) cache.delete_memoized(joined_communities, user.id) cache.delete_memoized(moderating_communities, user.id) notify = Notification(title=shorten_string('You have been un-banned from ' + community.title), url=f'/notifications', user_id=user.id, author_id=1) db.session.add(notify) user.unread_notifications += 1 db.session.commit() else: ... # todo: send chatmessage to remote user and federate it return redirect(url_for('community.community_moderate_banned', actor=community.link())) @bp.route('//notification', methods=['GET', 'POST']) @login_required def community_notification(community_id: int): # Toggle whether the current user is subscribed to notifications about this community's posts or not community = Community.query.get_or_404(community_id) existing_notification = NotificationSubscription.query.filter(NotificationSubscription.entity_id == community.id, NotificationSubscription.user_id == current_user.id, NotificationSubscription.type == NOTIF_COMMUNITY).first() if existing_notification: db.session.delete(existing_notification) db.session.commit() else: # no subscription yet, so make one if not community.user_is_banned(current_user): new_notification = NotificationSubscription(user_id=current_user.id, entity_id=community.id, type=NOTIF_COMMUNITY) db.session.add(new_notification) db.session.commit() member_info = CommunityMember.query.filter(CommunityMember.community_id == community.id, CommunityMember.user_id == current_user.id).first() # existing community members get their notification flag toggled if member_info and not member_info.is_banned: member_info.notify_new_posts = not member_info.notify_new_posts db.session.commit() else: # people who are not yet members become members, with notify on. if not community.user_is_banned(current_user): new_member = CommunityMember(community_id=community.id, user_id=current_user.id, notify_new_posts=True) db.session.add(new_member) db.session.commit() return render_template('community/_notification_toggle.html', community=community) @bp.route('//moderate', methods=['GET']) @login_required def community_moderate(actor): if current_user.banned: return show_ban_message() community = actor_to_community(actor) if community is not None: if community.is_moderator() or current_user.is_admin(): page = request.args.get('page', 1, type=int) search = request.args.get('search', '') local_remote = request.args.get('local_remote', '') reports = Report.query.filter_by(status=0, in_community_id=community.id) if local_remote == 'local': reports = reports.filter(Report.source_instance_id == 1) if local_remote == 'remote': reports = reports.filter(Report.source_instance_id != 1) reports = reports.filter(Report.status >= 0).order_by(desc(Report.created_at)).paginate(page=page, per_page=1000, error_out=False) next_url = url_for('community.community_moderate', page=reports.next_num) if reports.has_next else None prev_url = url_for('community.community_moderate', page=reports.prev_num) if reports.has_prev and page != 1 else None return render_template('community/community_moderate.html', title=_('Moderation of %(community)s', community=community.display_name()), community=community, reports=reports, current='reports', next_url=next_url, prev_url=prev_url, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) else: abort(401) else: abort(404) @bp.route('//moderate/subscribers', methods=['GET']) @login_required def community_moderate_subscribers(actor): community = actor_to_community(actor) if community is not None: if community.is_moderator() or current_user.is_admin(): page = request.args.get('page', 1, type=int) low_bandwidth = request.cookies.get('low_bandwidth', '0') == '1' subscribers = User.query.join(CommunityMember, CommunityMember.user_id == User.id).filter(CommunityMember.community_id == community.id) subscribers = subscribers.filter(CommunityMember.is_banned == False) # Pagination subscribers = subscribers.paginate(page=page, per_page=100 if not low_bandwidth else 50, error_out=False) next_url = url_for('community.community_moderate_subscribers', actor=actor, page=subscribers.next_num) if subscribers.has_next else None prev_url = url_for('community.community_moderate_subscribers', actor=actor, page=subscribers.prev_num) if subscribers.has_prev and page != 1 else None banned_people = User.query.join(CommunityBan, CommunityBan.user_id == User.id).filter(CommunityBan.community_id == community.id).all() return render_template('community/community_moderate_subscribers.html', title=_('Moderation of %(community)s', community=community.display_name()), community=community, current='subscribers', subscribers=subscribers, banned_people=banned_people, next_url=next_url, prev_url=prev_url, low_bandwidth=low_bandwidth, moderating_communities=moderating_communities(current_user.get_id()), joined_communities=joined_communities(current_user.get_id()), inoculation=inoculation[randint(0, len(inoculation) - 1)] ) else: abort(401) else: abort(404) @bp.route('/community//moderate_report//escalate', methods=['GET', 'POST']) @login_required def community_moderate_report_escalate(community_id, report_id): community = Community.query.get_or_404(community_id) if community.is_moderator() or current_user.is_admin(): report = Report.query.filter_by(in_community_id=community.id, id=report_id, status=REPORT_STATE_NEW).first() if report: form = EscalateReportForm() if form.validate_on_submit(): notify = Notification(title='Escalated report', url='/admin/reports', user_id=1, author_id=current_user.id) db.session.add(notify) report.description = form.reason.data report.status = REPORT_STATE_ESCALATED db.session.commit() flash(_('Admin has been notified about this report.')) # todo: remove unread notifications about this report # todo: append to mod log return redirect(url_for('community.community_moderate', actor=community.link())) else: form.reason.data = report.description return render_template('community/community_moderate_report_escalate.html', form=form) else: abort(401) @bp.route('/community//moderate_report//resolve', methods=['GET', 'POST']) @login_required def community_moderate_report_resolve(community_id, report_id): community = Community.query.get_or_404(community_id) if community.is_moderator() or current_user.is_admin(): report = Report.query.filter_by(in_community_id=community.id, id=report_id).first() if report: form = ResolveReportForm() if form.validate_on_submit(): report.status = REPORT_STATE_RESOLVED # Reset the 'reports' counter on the comment, post or user if report.suspect_post_reply_id: post_reply = PostReply.query.get(report.suspect_post_reply_id) post_reply.reports = 0 elif report.suspect_post_id: post = Post.query.get(report.suspect_post_id) post.reports = 0 elif report.suspect_user_id: user = User.query.get(report.suspect_user_id) user.reports = 0 db.session.commit() # todo: remove unread notifications about this report # todo: append to mod log if form.also_resolve_others.data: if report.suspect_post_reply_id: db.session.execute(text('UPDATE "report" SET status = :new_status WHERE suspect_post_reply_id = :suspect_post_reply_id'), {'new_status': REPORT_STATE_RESOLVED, 'suspect_post_reply_id': report.suspect_post_reply_id}) # todo: remove unread notifications about these reports elif report.suspect_post_id: db.session.execute(text('UPDATE "report" SET status = :new_status WHERE suspect_post_id = :suspect_post_id'), {'new_status': REPORT_STATE_RESOLVED, 'suspect_post_id': report.suspect_post_id}) # todo: remove unread notifications about these reports db.session.commit() flash(_('Report resolved.')) return redirect(url_for('community.community_moderate', actor=community.link())) else: return render_template('community/community_moderate_report_resolve.html', form=form) @bp.route('/community//moderate_report//ignore', methods=['GET', 'POST']) @login_required def community_moderate_report_ignore(community_id, report_id): community = Community.query.get_or_404(community_id) if community.is_moderator() or current_user.is_admin(): report = Report.query.filter_by(in_community_id=community.id, id=report_id).first() if report: # Set the 'reports' counter on the comment, post or user to -1 to ignore all future reports if report.suspect_post_reply_id: post_reply = PostReply.query.get(report.suspect_post_reply_id) post_reply.reports = -1 elif report.suspect_post_id: post = Post.query.get(report.suspect_post_id) post.reports = -1 elif report.suspect_user_id: user = User.query.get(report.suspect_user_id) user.reports = -1 db.session.commit() # todo: append to mod log if report.suspect_post_reply_id: db.session.execute(text('UPDATE "report" SET status = :new_status WHERE suspect_post_reply_id = :suspect_post_reply_id'), {'new_status': REPORT_STATE_DISCARDED, 'suspect_post_reply_id': report.suspect_post_reply_id}) # todo: remove unread notifications about these reports elif report.suspect_post_id: db.session.execute(text('UPDATE "report" SET status = :new_status WHERE suspect_post_id = :suspect_post_id'), {'new_status': REPORT_STATE_DISCARDED, 'suspect_post_id': report.suspect_post_id}) # todo: remove unread notifications about these reports db.session.commit() flash(_('Report ignored.')) return redirect(url_for('community.community_moderate', actor=community.link())) else: abort(404) @bp.route('/lookup//') def lookup(community, domain): if domain == current_app.config['SERVER_NAME']: return redirect('/c/' + community) exists = Community.query.filter_by(name=community, ap_domain=domain).first() if exists: return redirect('/c/' + community + '@' + domain) else: address = '!' + community + '@' + domain if current_user.is_authenticated: new_community = None new_community = search_for_community(address) if new_community is None: if g.site.enable_nsfw: flash(_('Community not found.'), 'warning') else: flash(_('Community not found. If you are searching for a nsfw community it is blocked by this instance.'), 'warning') else: if new_community.banned: flash(_('That community is banned from %(site)s.', site=g.site.name), 'warning') return render_template('community/lookup_remote.html', title=_('Search result for remote community'), new_community=new_community, subscribed=community_membership(current_user, new_community) >= SUBSCRIPTION_MEMBER) else: # send them back where they came from flash('Searching for remote communities requires login', 'error') referrer = request.headers.get('Referer', None) if referrer is not None: return redirect(referrer) else: return redirect('/')