import gc
import logging
import os
from datadog import DogStatsd
from ddtrace import tracer
from flask import Flask, g, render_template, request, session
from flask_cdn import CDN
from flask_moment import Moment
from htmlmin import minify
from raven.contrib.flask import Sentry
from raven.handlers.logging import SentryHandler
from everyclass.server.utils import web_consts
from everyclass.server.utils.common_helpers import plugin_available
from everyclass.server.utils.session import EncryptedSessionInterface
logger = logging.getLogger(__name__)
sentry = Sentry()
statsd = None
__app = None
try:
import uwsgidecorators
"""
使用 `uwsgidecorators.postfork` 装饰的函数会在 fork() 后的**每一个**子进程内被执行，执行顺序与这里的定义顺序一致
"""
@uwsgidecorators.postfork
def enable_gc():
"""重新启用垃圾回收"""
gc.set_threshold(700)
@uwsgidecorators.postfork
def init_plugins():
"""初始化日志、错误追踪、打点插件"""
from everyclass.rpc import init as init_rpc
from everyclass.common.flask import print_config
# Sentry
if plugin_available("sentry"):
sentry.init_app(app=__app)
sentry_handler = SentryHandler(sentry.client)
sentry_handler.setLevel(logging.WARNING)
logging.getLogger().addHandler(sentry_handler)
init_rpc(sentry=sentry)
logger.info('Sentry is inited because you are in {} mode.'.format(__app.config['CONFIG_NAME']))
# metrics
global statsd
statsd = DogStatsd(namespace=f"{__app.config['SERVICE_NAME']}.{os.environ.get('MODE').lower()}",
use_default_route=True)
init_rpc(logger=logger)
print_config(__app, logger)
@uwsgidecorators.postfork
def init_db():
"""初始化数据库连接"""
from everyclass.server.utils.db.postgres import init_pool as init_pg
# init_mongo(__app)
init_pg()
@uwsgidecorators.postfork
def fetch_remote_manifests():
"""
在 gevent 模式下，创建 Flask 对象时无法进行 HTTP 请求。因为此时 urllib2 是 gevent 补丁后的版本，而 gevent 引擎还没启动。
因此我们只能在 fork 后的每个进程中进行请求。
"""
cron_update_remote_manifest()
@uwsgidecorators.cron(0, -1, -1, -1, -1)
def daily_update_data_time(signum):
"""每天凌晨更新数据最后更新时间"""
cron_update_remote_manifest()
except ModuleNotFoundError:
pass
def cron_update_remote_manifest():
"""更新数据最后更新时间"""
from everyclass.rpc.http import HttpRpc
# 获取安卓客户端下载链接
android_manifest = HttpRpc.call(method="GET",
url="https://everyclass.cdn.admirable.pro/android/manifest.json",
retry=True)
android_ver = android_manifest['latestVersions']['mainstream']['versionCode']
__app.config['ANDROID_CLIENT_URL'] = android_manifest['releases'][android_ver]['url']
# 更新数据最后更新时间
_api_server_status = HttpRpc.call(method="GET",
url=__app.config['ENTITY_BASE_URL'] + '/info/service',
retry=True,
headers={'X-Auth-Token': __app.config['ENTITY_TOKEN']})
__app.config['DATA_LAST_UPDATE_TIME'] = _api_server_status["data"]["data_time"]
def create_app() -> Flask:
"""创建 flask app"""
from everyclass.server.utils.web_consts import MSG_INTERNAL_ERROR
from everyclass.server import plugin_available
from everyclass.server.utils import generate_error_response, api_helpers, base_exceptions
from everyclass.common.env import is_production
from everyclass.server.utils.web_consts import MSG_404
app = Flask(__name__,
static_folder='../../frontend/dist',
static_url_path='',
template_folder="../../frontend/templates")
# load app config
from everyclass.server.utils.config import get_config
_config = get_config()
app.config.from_object(_config) # noqa: T484
"""
每课统一日志机制
规则如下：
- DEBUG 模式下会输出 DEBUG 等级的日志，否则输出 INFO 及以上等级的日志
- 日志为 JSON 格式，会被节点上的 agent 采集并发送到 datadog，方便结合 metrics 和 APM 数据分析
- WARNING 以上级别的输出到 Sentry 做错误聚合
日志等级：
critical – for errors that lead to termination
error – for errors that occur, but are handled
warning – for exceptional circumstances that might not be errors
notice – for non-error messages you usually want to see
info – for messages you usually don’t want to see
debug – for debug messages
Sentry：
https://docs.sentry.io/clients/python/api/#raven.Client.captureMessage
- stack 默认是 False
"""
if app.config['DEBUG']:
logging.getLogger().setLevel(logging.DEBUG)
else:
logging.getLogger().setLevel(logging.INFO)
# CDN
CDN(app)
# moment
Moment(app)
# encrypted session
app.session_interface = EncryptedSessionInterface()
# 导入并注册 blueprints
from everyclass.server.calendar.views import calendar_bp
from everyclass.server.calendar.views_api import calendar_api_bp
from everyclass.server.entity.views import entity_bp
from everyclass.server.entity.views_api import entity_api_bp
from everyclass.server.user.views import user_bp
from everyclass.server.user.views_api import user_api_bp
from everyclass.server.course.views import course_bp
from everyclass.server.course.views_api import course_api_bp
from everyclass.server.views_main import main_blueprint
app.register_blueprint(calendar_bp)
app.register_blueprint(entity_bp)
app.register_blueprint(user_bp, url_prefix='/user')
app.register_blueprint(entity_api_bp, url_prefix='/mobile/entity')
app.register_blueprint(user_api_bp, url_prefix='/mobile/user')
app.register_blueprint(calendar_api_bp, url_prefix='/mobile/calendar')
if 'course' in _config.FEATURE_GATING and _config.FEATURE_GATING['course']:
app.register_blueprint(course_api_bp, url_prefix='/mobile/course')
app.register_blueprint(course_bp, url_prefix='/course')
app.register_blueprint(main_blueprint)
# 初始化 RPC 模块
from everyclass.rpc.auth import Auth
if 'AUTH_BASE_URL' in app.config:
Auth.set_base_url(app.config['AUTH_BASE_URL'])
@app.before_request
def set_user_id():
"""在请求之前设置 session uid，方便 APM 标识用户"""
from everyclass.server.utils.web_consts import SESSION_CURRENT_USER, SESSION_USER_SEQ
from everyclass.server.user import service as user_service
if not session.get('user_id', None) and request.endpoint not in ("main.health_check", "static"):
logger.info(f"Give a new user ID for new user. endpoint: {request.endpoint}")
session['user_id'] = user_service.get_user_id()
if session.get('user_id', None):
tracer.current_root_span().set_tag("user_id", session[SESSION_USER_SEQ]) # 唯一用户 ID
if session.get(SESSION_CURRENT_USER, None):
tracer.current_root_span().set_tag("username", session[SESSION_CURRENT_USER].identifier) # 学号或教工号
@app.before_request
def log_request():
"""日志中记录请求"""
logger.info(f'Request received: {request.method} {request.path}')
@app.after_request
def response_minify(response):
"""用 htmlmin 压缩 HTML，减轻带宽压力"""
if app.config['HTML_MINIFY'] and response.content_type == u'text/html; charset=utf-8':
response.set_data(minify(response.get_data(as_text=True)))
return response
from everyclass.server.utils.db.postgres import db_session
@app.teardown_appcontext
def shutdown_db_session(exception=None):
db_session.remove()
@app.template_filter('versioned')
def version_filter(filename):
"""
模板过滤器。如果 STATIC_VERSIONED，返回类似 'style-v1-c012dr.css' 的文件，而不是 'style-v1.css'
:param filename: 文件名
:return: 新的文件名
"""
if app.config['STATIC_VERSIONED']:
if filename[:4] == 'css/':
new_filename = app.config['STATIC_MANIFEST'][filename[4:]]
return 'css/' + new_filename
elif filename[:3] == 'js/':
new_filename = app.config['STATIC_MANIFEST'][filename[3:]]
return new_filename
else:
return app.config['STATIC_MANIFEST'][filename]
return filename
@app.context_processor
def inject_consts():
"""允许在模板中使用常量模块，以便使用session key等常量而不用在模板中硬编码"""
return dict(consts=web_consts,
api_base_url=app.config['MOBILE_API_BASE_URL'])
@app.errorhandler(404)
def page_not_found(error):
if request.path.startswith('/mobile'):
return generate_error_response(None, api_helpers.STATUS_CODE_INVALID_REQUEST, "no such API")
return render_template('common/error.html', message=MSG_404)
@app.errorhandler(base_exceptions.BizException)
def handle_biz_exception(error: base_exceptions.BizException):
if request.path.startswith("/mobile"):
if isinstance(error, base_exceptions.InternalError):
logger.error(repr(error))
# 业务错误的status_message可以对外展示
actual_error = {'status_message_overwrite': error.status_message}
return generate_error_response(None, error.status_code, **actual_error)
@app.errorhandler(500)
def internal_server_error(error):
if request.path.startswith("/mobile"):
# 对于非业务错误，生产环境中不进行返回，其他环境中可返回
actual_error = {
'status_message_overwrite': f"server internal error: {repr(error.original_exception)}"} if not is_production() else {}
return generate_error_response(None, api_helpers.STATUS_CODE_INTERNAL_ERROR, **actual_error)
if plugin_available("sentry"):
return render_template('common/error.html',
message=MSG_INTERNAL_ERROR,
event_id=g.sentry_event_id,
public_dsn=sentry.client.get_public_dsn('https'))
return f"<h4>500 Error: {repr(error.original_exception)}</h4><br>You are seeing this page because Sentry is not available."
global __app
__app = app
return app
