server.py

from flask import Flask, g, request, url_for, redirect, session, render_template, flash, Response, make_response
from werkzeug.routing import Rule
from functools import wraps
from datetime import date, timedelta, datetime, time, MINYEAR
import os
import sys
import hashlib
import random
import traceback
import string
from socket import gethostname
from ipaddress import ip_address, ip_network
import math
import locale
import base64
import json

locale.setlocale(locale.LC_ALL, 'de_DE.utf8')

app = Flask(__name__)

config = app.config
config.from_pyfile('config.py.example', silent=True)
if sys.argv[0].endswith('run.py'): 
	config['SQLITE_INIT_DATA'] = True
	config['DEBUG'] = True
config.from_pyfile('config.py', silent=True)
if sys.argv[0].endswith('tests.py'):
	print('running in test mode')
	import tempfile
	# ensure we always use a clean sqlite db for tests
	config['DB_ENGINE'] = 'sqlite'
	config['SQLITE_DB'] = tempfile.mktemp(prefix='flasktestingtmp')
	print('DB File: {}'.format(config['SQLITE_DB']))
	config['SQLITE_INIT_DATA'] = True
	config['SQLITE_INIT_SCHEMA'] = True
	config['DEBUG'] = True
	config['DISABLE_SCHEDULER'] = True
if config['DEBUG']:
	app.jinja_env.auto_reload = True

if not config.get('SECRET_KEY', None):
	config['SECRET_KEY'] = os.urandom(24)

from db import query, modify, show, searchquery
from mail import notify_mods, notify_admins
from ldap import ldapauth
from legacy import legacy_index
from scheduler import sched_func

mod_endpoints = []

def mod_required(func):
	mod_endpoints.append(func.__name__)
	@wraps(func)
	def decorator(*args, **kwargs):
		if not ismod():
			flash('Diese Funktion ist nur für Moderatoren verfügbar!')
			return redirect(url_for('login', ref=request.url))
		else:
			return func(*args, **kwargs)
	return decorator

def evalperm(perms):
	cperms = []
	lperms = []
	vperms = []
	for perm in perms:
		if perm['course_id']:
			cperms.append(perm)
		elif perm['lecture_id']:
			lperms.append(perm)
		elif perm['video_id']:
			vperms.append(perm)
	if vperms:
		return vperms
	elif lperms:
	 	return lperms
	elif cperms:
		return cperms
	return [{'type': 'public'}]

from template_helper import *

app.jinja_env.globals['navbar'] = []
# iconlib can be 'bootstrap'
# ( see: http://getbootstrap.com/components/#glyphicons )
# or 'fa'
# ( see: http://fontawesome.io/icons/ )
def register_navbar(name, iconlib='bootstrap', icon=None):
	def wrapper(func):
		endpoint = func.__name__
		app.jinja_env.globals['navbar'].append((endpoint, name, iconlib, icon, not endpoint in mod_endpoints))
		return func
	return wrapper

def render_endpoint(endpoint, flashtext=None, **kargs):
	if flashtext:
		flash(flashtext)
	# request.endpoint is used for navbar highlighting
	request.url_rule = Rule(request.path, endpoint=endpoint)
	return app.view_functions[endpoint](**kargs)

def handle_errors(endpoint, text, code, *errors, **epargs):
	def wrapper(func):
		@wraps(func)
		def decorator(*args, **kwargs):
			try:
				return func(*args, **kwargs)
			except errors:
				if endpoint:
					return make_response(render_endpoint(endpoint, text, **epargs), code)
				else:
					return text, code
		return decorator
	return wrapper

@app.errorhandler(404)
@app.route('/invalidpath')
def handle_not_found(e=None):
	return render_endpoint('index', 'Diese Seite existiert nicht!'), 404

@app.errorhandler(500)
@app.errorhandler(Exception)
def handle_internal_error(e):
	traceback.print_exc()
	notify_admins('endpoint_exception', traceback=traceback.format_exc())
	return render_template('500.html', online=True), 500

@sched_func(5*60, firstdelay=0)
def dump_error_page():
	if 'ERROR_PAGE' not in config:
		return
	request.url_rule = Rule(request.path, endpoint='handle_internal_error')
	text = render_template('500.html')
	f = open(config['ERROR_PAGE'], 'w')
	f.write(text)
	f.close()

def genlive(streams):
	for stream in streams:
		stream['visible'] = True
		stream['downloadable'] = False
		stream['path'] = 'pub/hls/%s.m3u8'%stream['livehandle']
		stream['file_size'] = 0
	return streams


@app.route('/')
@register_navbar('Home', icon='home')
def index():
	# handle legacy urls...
	result = legacy_index()
	if result:
		return result

	start = date.today()
	end = start + timedelta(days=7)
	upcomming = query('''
		SELECT lectures.*, streams.active AS nowlive, "course" AS sep, courses.*
		FROM lectures
		JOIN courses ON (lectures.course_id = courses.id)
		LEFT JOIN streams ON lectures.id = streams.lecture_id
		WHERE (time > ?) AND (time < ?) AND (? OR (lectures.visible AND courses.visible AND courses.listed)) AND NOT lectures.norecording
		ORDER BY time ASC LIMIT 30''', start, end, ismod())
	for i in upcomming:
		i['date'] = i['time'].date()
	latestvideos=query('''
		SELECT lectures.*, "course" AS sep, courses.*
		FROM lectures
		LEFT JOIN videos ON (videos.lecture_id = lectures.id)
		LEFT JOIN courses on (courses.id = lectures.course_id)
		WHERE (? OR (courses.visible AND courses.listed AND lectures.visible AND videos.visible))
		GROUP BY videos.lecture_id
		ORDER BY MAX(videos.time_created) DESC
		LIMIT 6	''',ismod())
	livestreams = query('''SELECT streams.handle AS livehandle, lectures.*, "course" AS sep, courses.*
		FROM streams
		JOIN lectures ON lectures.id = streams.lecture_id
		JOIN courses ON courses.id = lectures.course_id
		WHERE streams.active AND (? OR (streams.visible AND courses.visible AND courses.listed AND lectures.visible))
		''', ismod())
	featured = query('SELECT * FROM featured WHERE (? OR visible) ORDER BY `order`', ismod())
	featured = list(filter(lambda x: not x['deleted'], featured))
	for item in featured:
		if item['type'] == 'courses':
			if item['param'] not in ['title', 'semester', 'organizer', 'subject']:
				continue
			item['courses'] = query('SELECT * FROM courses WHERE (visible AND listed) AND `%s` = ? ORDER BY `%s`'%(item['param'], item['param']), item['param2'])
		elif item['type'] == 'video':
			item['lecture'] = {'id': item['param']}
			streams = query('''SELECT streams.handle AS livehandle, streams.lecture_id, "formats" AS sep, formats.*
					FROM streams
					JOIN lectures ON lectures.id = streams.lecture_id
					JOIN formats ON formats.keywords = "hls"
					WHERE streams.active AND streams.visible AND lectures.id = ?
					''', item['param'])
			item['videos'] = query('''
					SELECT videos.*, "formats" AS sep, formats.*
					FROM videos
					JOIN formats ON (videos.video_format = formats.id)
					WHERE videos.lecture_id = ? AND videos.visible
					ORDER BY formats.prio DESC
					''', item['param'])+genlive(streams)
	return render_template('index.html', latestvideos=livestreams+latestvideos, upcomming=upcomming, featured=featured)

@app.route('/courses')
@register_navbar('Videos', icon='film')
def courses():
	courses = query('SELECT * FROM courses WHERE (? OR (visible AND listed)) ORDER BY lower(semester), lower(title)', ismod())
	chapters = {}
	for i in query('SELECT lectures.course_id AS id, COUNT(chapters.id) AS c FROM chapters JOIN lectures ON chapters.lecture_id = lectures.id WHERE NOT chapters.visible AND NOT chapters.deleted GROUP BY lectures.course_id'):
		chapters[i['id']] = i['c']
	for course in courses:
		course['chapter_count'] = chapters.get(course['id'], 0)
		if course['semester'] == '':
			course['semester'] = 'zeitlos'
	groupedby = request.args.get('groupedby')
	if groupedby not in ['title', 'semester', 'organizer', 'subject']:
		groupedby = 'semester'
	return render_template('courses.html', courses=courses, groupedby=groupedby)

@app.route('/<handle>')
@app.route('/<int:id>')
@handle_errors('courses', 'Diese Veranstaltung existiert nicht!', 404, IndexError)
def course(id=None, handle=None):
	if id:
		course = query('SELECT * FROM courses WHERE id = ? AND (? OR visible)', id, ismod())[0]
	else:
		course = query('SELECT * FROM courses WHERE handle = ? AND (? OR visible)', handle, ismod())[0]
	course['perm'] = query('SELECT * FROM perm WHERE (NOT perm.deleted) AND course_id = ? ORDER BY type', course['id'])
	perms = query('SELECT perm.* FROM perm JOIN lectures ON (perm.lecture_id = lectures.id) WHERE (NOT perm.deleted) AND lectures.course_id = ? ORDER BY perm.type', course['id'])
	chapters = {}
	for i in query('SELECT lectures.id AS id, COUNT(chapters.id) AS c FROM chapters JOIN lectures ON chapters.lecture_id = lectures.id WHERE lectures.course_id = ? AND NOT chapters.visible AND NOT chapters.deleted GROUP BY chapters.lecture_id;', course['id']):
		chapters[i['id']] = i['c']
	lectures = query('SELECT * FROM lectures WHERE course_id = ? AND (? OR visible) ORDER BY time, duration DESC', course['id'], ismod())
	for lecture in lectures:
		lecture['perm'] = []
		lecture['perm'] += course['perm']
		lecture['course'] = course
		lecture['chapter_count'] = chapters.get(lecture['id'], 0)
		for perm in perms:
			if perm['lecture_id'] == lecture['id']:
				lecture['perm'].append(perm)
	videos = query('''
			SELECT videos.*, (videos.downloadable AND courses.downloadable) as downloadable, "formats" AS sep, formats.*
			FROM videos
			JOIN lectures ON (videos.lecture_id = lectures.id)
			JOIN formats ON (videos.video_format = formats.id)
			JOIN courses ON (lectures.course_id = courses.id)
			WHERE lectures.course_id= ? AND (? OR videos.visible)
			ORDER BY lectures.time, formats.prio DESC
			''', course['id'], ismod())
	livestreams = query('''SELECT streams.handle AS livehandle, streams.lecture_id, "formats" AS sep, formats.*
			FROM streams
			JOIN lectures ON lectures.id = streams.lecture_id
			JOIN formats ON formats.keywords = "hls"
			WHERE streams.active AND (? OR streams.visible) AND lectures.course_id = ?
			''', ismod(), course['id'])
	chapters = []
	if course['coursechapters']:
		chapters = query('SELECT chapters.* FROM chapters JOIN lectures ON lectures.id = chapters.lecture_id WHERE lectures.course_id = ? AND NOT chapters.deleted AND chapters.visible ORDER BY time ASC', course['id'])
	videos += genlive(livestreams)
	responsible = query('''SELECT users.*, responsible.course_id AS responsible
			FROM users
			LEFT JOIN responsible ON (responsible.user_id = users.id AND responsible.course_id = ?)
			WHERE users.fsacc != "" AND users.level > 0
			ORDER BY responsible DESC, users.realname ASC''', course['id'])
	return render_template('course.html', course=course, lectures=lectures, videos=videos, chapters=chapters, responsible=responsible)

@app.route('/faq')
@register_navbar('FAQ', icon='question-sign')
def faq():
	return render_template('faq.html')

@app.route('/<course>/<int:id>')
@app.route('/<int:courseid>/<int:id>')
@app.route('/<course>/<int:id>/embed', endpoint='embed')
@app.route('/<int:courseid>/<int:id>/embed', endpoint='embed')
@handle_errors('course', 'Diese Vorlesung existiert nicht!', 404, IndexError)
def lecture(id, course=None, courseid=None):
	lecture = query('SELECT * FROM lectures WHERE id = ? AND (? OR visible)', id, ismod())[0]
	videos = query('''
			SELECT videos.*, (videos.downloadable AND courses.downloadable) as downloadable, "formats" AS sep, formats.*
			FROM videos
			JOIN formats ON (videos.video_format = formats.id)
			JOIN courses ON (courses.id = ?)
			WHERE videos.lecture_id = ? AND (? OR videos.visible)
			ORDER BY formats.prio DESC
			''', lecture['course_id'], lecture['id'], ismod())
	livestreams = query('''SELECT streams.handle AS livehandle, streams.lecture_id, "formats" AS sep, formats.*
			FROM streams
			JOIN lectures ON lectures.id = streams.lecture_id
			JOIN formats ON formats.keywords = "hls"
			WHERE streams.active AND (? OR streams.visible) AND lectures.id = ?
			''', ismod(), id)
	videos += genlive(livestreams)
	perms = query('SELECT perm.* FROM perm WHERE ((NOT perm.deleted) AND (perm.lecture_id = ? OR perm.course_id = ?))',
			lecture['id'], lecture['course_id'])
	if not videos:
		if lecture['live'] and lecture['time'] > datetime.now()-timedelta(minutes=30) and lecture['time']-timedelta(hours=20) < datetime.now():
			flash('Der Livestream beginnt um '+human_time(lecture['time'])+' Uhr.')
		elif lecture['time'] > datetime.now():
			flash('Diese Vorlesung hat noch nicht stattgefunden!')
		else:
			flash('Zu dieser Vorlesung wurden noch keine Videos veröffentlicht!')
	courses = query('SELECT * FROM courses WHERE id = ? AND (? OR visible)', lecture['course_id'], ismod())
	if not courses:
		return render_endpoint('courses', 'Diese Veranstaltung existiert nicht!'), 404
	chapters = query('SELECT * FROM chapters WHERE lecture_id = ? AND NOT deleted AND (? OR visible) ORDER BY time ASC', id, ismod())
	username = password = None
	if request.authorization:
		username = request.authorization.username
		password = request.authorization.password
	if not checkperm(perms, username=username, password=password):
		mode, text = permdescr(perms)
		if mode == 'rwth':
			flash(text+'. <a target="_blank" class="reloadonclose" href="'+url_for('start_rwthauth')+'">Hier authorisieren</a>.', category='player')
		elif mode == 'l2p':
			if 'l2p_courses' in session:
				flash(text+'. Du bist kein Teilnehmer des L2P-Kurses! <a target="_blank" class="reloadonclose" href="'+url_for('start_l2pauth')+'">Kurse aktualisieren</a>.', category='player')
			else:
				flash(text+'. <a target="_blank" class="reloadonclose" href="'+url_for('start_l2pauth')+'">Hier authorisieren</a>.', category='player')
		else:
			flash(text+'.', category='player')
	return render_template('embed.html' if request.endpoint == 'embed' else 'lecture.html', course=courses[0], lecture=lecture, videos=videos, chapters=chapters, seek=request.args.get('t'))


@app.route('/search')
def search():
	if 'q' not in request.args:
		return redirect(url_for('index'))
	q = request.args['q']
	courses = searchquery(q, '*', ['title', 'short', 'organizer', 'subject', 'description'],
			'courses', 'WHERE (? OR (visible AND listed)) GROUP BY id ORDER BY _score DESC, semester DESC LIMIT 20', ismod())
	lectures = searchquery(q, 'lectures.*, courses.visible AS coursevisible, courses.listed, courses.id AS courses_id, courses.visible AS courses_visible, courses.listed AS courses_listed, courses.title AS courses_title, courses.short AS courses_short, courses.handle AS courses_handle, courses.organizer AS courses_organizer, courses.subject AS courses_subject, courses.credits AS courses_credits, courses.created_by AS courses_created_by, courses.time_created AS courses_time_created, courses.time_updated AS courses_time_updated, courses.semester AS courses_semester, courses.downloadable AS courses_downloadable, courses.embedinvisible AS courses_embedinvisible, courses.description AS courses_description, courses.internal AS courses_internal',
			['lectures.title', 'lectures.comment', 'lectures.speaker', 'courses.short'],
			'lectures LEFT JOIN courses on (courses.id = lectures.course_id)',
			'WHERE (? OR (coursevisible AND listed AND visible)) GROUP BY id ORDER BY _score DESC, time DESC LIMIT 30', ismod())
	for lecture in lectures:
		lecture['course'] = {}
		for key in lecture:
			if key.startswith('courses_'):
				lecture['course'][key[8:]] = lecture[key]
	return render_template('search.html', searchtext=request.args['q'], courses=courses, lectures=lectures)

def check_mod(user, groups):
	if not user:
		return False
	for group in config['LDAP_GROUPS']:
		if group in groups:
			return True
	return False

@app.route('/internal/login', methods=['GET', 'POST'])
def login():
	if request.method == 'GET':
		return render_template('login.html')
	userinfo, groups = ldapauth(request.form.get('user'), request.form.get('password'))
	user = userinfo.get('uid')
	if not check_mod(user, groups):
		flash('Login fehlgeschlagen!')
		return make_response(render_template('login.html'), 403)
	session['user'] = userinfo
	dbuser = query('SELECT * FROM users WHERE name = ?', user)
	if not dbuser:
		modify('INSERT INTO users (name, realname, fsacc, level, calendar_key, rfc6238) VALUES (?, ?, ?, 1, "", "")', user, session['user']['givenName'], user)
		dbuser = query('SELECT * FROM users WHERE name = ?', user)
	session['user']['dbid'] = dbuser[0]['id']
	session['_csrf_token'] = ''.join(random.SystemRandom().choice(string.ascii_letters + string.digits) for _ in range(64))
	session.permanent = True
	return redirect(request.values.get('ref', url_for('index')))

@app.route('/internal/logout', methods=['GET', 'POST'])
def logout():
	session.pop('user', None)
	return redirect(request.values.get('ref', url_for('index')))

@app.route('/internal/auth')
def auth(): # For use with nginx auth_request
	if 'X-Original-Uri' not in request.headers:
		return 'Internal Server Error', 500
	url = request.headers['X-Original-Uri'].lstrip(config['VIDEOPREFIX'])
	if request.cookies.get('tracking', '') and request.cookies['tracking'].isdigit():
		cookie = int(request.cookies['tracking'])
	else:
		cookie = random.getrandbits(8*8-1)
	if url.endswith('jpg') or ismod():
		return "OK", 200
	if url.startswith('pub/hls/'):
		handle = url[len('pub/hls/'):].split('_')[0].split('.')[0]
		perms = query('''SELECT lectures.id AS lecture, perm.*
				FROM streams
				JOIN lectures ON (streams.lecture_id = lectures.id)
				JOIN courses ON (lectures.course_id = courses.id)
				LEFT JOIN perm ON ((lectures.id = perm.lecture_id OR courses.id = perm.course_id) AND NOT perm.deleted)
				WHERE streams.handle = ?
				AND (courses.visible AND lectures.visible AND streams.visible)
				ORDER BY perm.video_id DESC, perm.lecture_id DESC, perm.course_id DESC''', handle)
	else:
		perms = query('''SELECT videos.path, videos.id AS vid, perm.*
				FROM videos
				JOIN lectures ON (videos.lecture_id = lectures.id)
				JOIN courses ON (lectures.course_id = courses.id)
				LEFT JOIN perm ON ((videos.id = perm.video_id OR lectures.id = perm.lecture_id OR courses.id = perm.course_id) AND NOT perm.deleted)
				WHERE videos.path = ?
				AND (courses.visible AND lectures.visible AND videos.visible)
				ORDER BY perm.video_id DESC, perm.lecture_id DESC, perm.course_id DESC''',
				url)
	if not perms:
		return "Not found", 404
	auth = request.authorization
	username = password = None
	if auth:
		username = auth.username
		password = auth.password
	if checkperm(perms, username=username, password=password):
		try:
			if not url.startswith('pub/hls/'):
				modify('INSERT INTO log (id, `time`, `date`, video, source) VALUES (?, ?, ?, ?, 1)', cookie, datetime.now(), datetime.combine(date.today(), time()), perms[0]['vid'])
			elif url.endswith('.ts'):
				fmt = url.split('_')[-1].split('-')[0]
				seg = url.split('.')[0].split('-')[-1]
				modify('INSERT INTO hlslog (id, `time`, segment, lecture, handle, format) VALUES (?, ?, ?, ?, ?, ?)', cookie, datetime.now(), seg, perms[0]['lecture'], handle, fmt)
		except:
			pass
		r = make_response('OK', 200)
		r.set_cookie('tracking', str(cookie), max_age=2147483647) # Many many years
		return r
	password_auth = False
	for perm in perms:
		if perm['type'] == 'password':
			password_auth = True
			break
	if password_auth:
		return Response("Login required", 401, {'WWW-Authenticate': 'Basic realm="Login Required"'})
	return "Not allowed", 403

@app.route('/files/<filename>')
def files(filename):
	return redirect(config['VIDEOPREFIX']+'/'+filename)

@app.route('/sitemap.xml')
def sitemap():
	pages=[]
	# static pages
	for rule in app.url_map.iter_rules():
		if 'GET' in rule.methods and len(rule.arguments)==0:
			if rule.endpoint not in mod_endpoints:
				pages.append([rule.rule])
	for i in query('select * from courses where visible and listed'):
		pages.append([url_for('course',handle=i['handle'])])
		for j in query('select * from lectures where (course_id = ? and visible)',i['id']):
			pages.append([url_for('lecture',course=i['handle'],id=j['id'])])


	return Response(render_template('sitemap.xml', pages=pages), 200, {'Content-Type': 'application/atom+xml'} )

@app.route('/internal/dbstatus')
@register_navbar('DB-Status', icon='ok')
@mod_required
def dbstatus():
	hosts = set()
	clusters = {}
	status = {}
	variables = {}
	for host in config.get('MYSQL_DBSTATUS_HOSTS', [])+[config.get('MYSQL_HOST', None)]:
		try:
			for _host in show('SHOW VARIABLES LIKE "wsrep_cluster_address"', host=host)['wsrep_cluster_address'][len('gcomm://'):].split(','):
				hosts.add(_host)
		except:
			pass
	for host in sorted(list(hosts)):
		try:
			status[host] = show('SHOW GLOBAL STATUS LIKE "wsrep%"', host=host)
			variables[host] = show('SHOW GLOBAL VARIABLES LIKE "wsrep%"', host=host)
		except:
			status[host] = {'wsrep_cluster_state_uuid': '', 'wsrep_local_state_comment': 'Not reachable', 'wsrep_cluster_conf_id': '0', 'wsrep_cluster_status': 'Unknown'}
			variables[host] = {'wsrep_node_name': host, 'wsrep_cluster_name': 'unknown'}
		cluster = variables[host]['wsrep_cluster_name']+'-'+status[host]['wsrep_cluster_conf_id']
		if cluster not in clusters:
			clusters[cluster] = []
		clusters[cluster].append(host)
	return render_template('dbstatus.html', clusters=clusters, statuses=status, vars=variables), 200

def date_json_handler(obj):
	return obj.isoformat() if hasattr(obj, 'isoformat') else obj

from jobs import job_handler, schedule_job
from edit import edit_handler
import feeds
import importer
import stats
if 'ICAL_URL' in config:
	import meetings
import l2pauth
import sorter
import encoding
import timetable
import chapters
import icalexport
import livestreams