问题描述
我有一个内置于 Flask 的 Web 应用程序,可以在其中捕获推文(使用 Tweepy 库)并显示在前端。我使用 Socket IO 在前端实时显示推文。
我的代码在本地运行时运行良好。推文立即出现。
但是,当我对 Web 应用程序进行 Docker 化时,前端不会立即更新。显示更改需要一些时间(有时我认为由于缓慢而导致推文丢失)
以下是我网站的代码摘录:
fortsocket.js
$(document).ready(function () {
/************************************/
/*********** My Functions ***********/
/************************************/
function stream_active_setup() {
$("#favicon").attr("href","/static/icons/fortnite-active.png");
$("#stream-status-ic").attr("src","/static/icons/stream-active.png");
$("#stream-status-text").text("Live stream active");
}
function stream_inactive_setup() {
$("#favicon").attr("href","/static/icons/fortnite-inactive.png");
$("#stream-status-ic").attr("src","/static/icons/stream-inactive.png");
$("#stream-status-text").text("Live stream inactive");
}
/*********************************/
/*********** My Events ***********/
/*********************************/
// Socket connection to server
// Prometheus
//var socket = io.connect('http://104.131.173.145:8083');
// Local
var socket = io.connect(window.location.protocol + '//' + document.domain + ':' + location.port);
// Heroku
//var socket = io.connect('https://fortweet.herokuapp.com/');
// Send a hello to kNow
// if a stream is already active
socket.on('connect',() => {
socket.emit('hello-stream','hello-stream');
});
// Listene for reply from hello
socket.on('hello-reply',function (bool) {
if (bool == true) {
stream_active_setup()
} else {
stream_inactive_setup()
}
});
// Listens for tweets
socket.on('stream-results',function (results) {
// Insert tweets in divs
$('#live-tweet-container').prepend(`
<div class="row justify-content-md-center mt-3">
<div class="col-md-2">
<img width="56px" height="56px" src="${results.profile_pic !== "" ? results.profile_pic : "/static/icons/profile-pic.png"}" class="mx-auto d-block rounded" alt="">
</div>
<div class="col-md-8 my-auto">
<div><b>${results.author}</b></div>
<div>${results.message}</div>
</div>
</div>
`);
});
// Listener for when a stream of tweets starts
socket.on('stream-started',function (bool) {
if (bool == true) {
stream_active_setup()
}
});
// Listener for when a stream of tweets ends
socket.on('stream-ended',function (bool) {
if (bool == true) {
stream_inactive_setup()
}
});
});
init.py
# Create the app
app = create_app()
# JWT Configurations
jwt = JWTManager(app)
# Socket IO
socketio = SocketIO(app,cors_allowed_origins="*")
# CORS
CORS(app)
app.config["CORS_HEADERS"] = "Content-Type"
# Creates default admins and insert in db
create_default_admin()
# Main error handlers
@app.errorhandler(404) # Handling HTTP 404 NOT FOUND
def page_not_found(e):
return Err.ERROR_NOT_FOUND
# Listen for hello emit data
# from client
@socketio.on("hello-stream")
def is_stream_active(hello_stream):
emit("hello-reply",streamer.StreamerInit.is_stream_active(),broadcast=True)
streamer.py
import time
import tweepy
import threading as Coroutine
import app.messages.constants as Const
import app.setup.settings as settings_mod
import app.models.tweet as tweet_mod
import app.services.logger as logger
import app
class FStreamListener(tweepy.StreamListener):
def __init__(self):
self.start_time = time.time()
self.limit = settings_mod.TwitterSettings.get_instance().stream_time
logger.get_logger().debug("Live capture has started")
# Notify client that a live capture will start
app.socketio.emit(
"stream-started",True,broadcast=True,)
super(FStreamListener,self).__init__()
def on_status(self,status):
if (time.time() - self.start_time) < self.limit:
# Create tweet object
forttweet = tweet_mod.TweetModel(
status.source,status.user.name,status.user.profile_background_image_url_https,status.text,status.created_at,status.user.location,)
# Emit to socket
app.socketio.emit(
"stream-results",{
"profile_pic": forttweet.profile_pic,"author": forttweet.author,"message": forttweet.message,},)
# Add to database
forttweet.insert()
return True
else:
logger.get_logger().debug("Live capture has ended")
# Notify client that a live capture has ended
app.socketio.emit(
"stream-ended",)
# Stop the loop of streaming
return False
def on_error(self,status):
logger.get_logger().debug(f"An error occurred while fetching tweets: {status}")
raise Exception(f"An error occurred while fetching tweets: {status}")
class StreamerInit:
# [Private] Twitter configurations
def __twitterInstantiation(self):
# Get settings instance
settings = settings_mod.TwitterSettings.get_instance()
# Auths
auth = tweepy.OAuthHandler(settings.consumer_key,settings.consumer_secret,)
auth.set_access_token(
settings.access_token,settings.access_token_secret,)
# Get API
api = tweepy.API(auth)
# Live Tweets Streaming
myStreamListener = FStreamListener()
myStream = tweepy.Stream(auth=api.auth,listener=myStreamListener)
myStream.filter(track=settings.filters)
def start(self):
for coro in Coroutine.enumerate():
if coro.name == Const.FLAG_TWEETS_LIVE_CAPTURE:
return False
stream = Coroutine.Thread(target=self.__twitterInstantiation)
stream.setName(Const.FLAG_TWEETS_LIVE_CAPTURE)
stream.start()
return True
@staticmethod
def is_stream_active():
for coro in Coroutine.enumerate():
if coro.name == Const.FLAG_TWEETS_LIVE_CAPTURE:
return True
return False
在单击按钮时调用 streamer.py
Dockerfile
# Using python 3.7 in Alpine
FROM python:3.6.5-stretch
# Set the working directory to /app
workdir /app
# copy the current directory contents into the container at /app
ADD . /app
RUN apt-get update -y && apt-get upgrade -y && pip install -r requirements.txt
# Run the command
ENTRYPOINT ["uwsgi","app.ini"]
#ENTRYPOINT ["./entry.sh"]
docker-compose.yml
version: "3.8"
services:
fortweet:
container_name: fortweet
image: mervin16/fortweet:dev
build: ./
env_file:
- secret.env
networks:
plutusnet:
ipv4_address: 172.16.0.10
expose:
- 8083
restart: always
Nginx_fortweet:
image: Nginx
container_name: Nginx_fortweet
ports:
- "8083:80"
networks:
plutusnet:
ipv4_address: 172.16.0.100
volumes:
- ./Nginx/Nginx.conf:/etc/Nginx/conf.d/default.conf
depends_on:
- fortweet
restart: always
networks:
plutusnet:
name: plutus_network
driver: bridge
ipam:
driver: default
config:
- subnet: 172.16.0.0/24
gateway: 172.16.0.1
app.ini
[uwsgi]
module = run:app
master = true
processes = 5
# Local & Prometheus
http-socket = 0.0.0.0:8083
http-websockets = true
chmod-socket = 660
vacuum = true
die-on-term = true
要获得完整的更新代码,您可以在分支 dev/mervin
感谢任何帮助。
解决方法
为了查看 ipv6 是否负责,我建议您关闭所有内容
打开 /etc/sysctl.conf
并添加以下几行以禁用 ipv6
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1
运行 sudo sysctl -p
以使更改生效
再次启动nginx和docker
如果您没有发现任何区别,那么您可以将设置更改为 0 并重新运行 sysctl -p
并告诉我
很遗憾,没有配置我无法重现该问题,因此我无法验证我的答案。
我在 JP 的博客上找到了类似的问题:Performance problems with Flask and Docker
简而言之,可能是容器上同时具有 IPv6 和 IPv4 配置导致了问题。 为了验证问题:
- 运行泊坞窗
- 进入正在运行的容器并更改主机文件,使其不会将 IPv6 映射到 localhost
- 在容器内再次运行应用程序
如果应用运行顺利,那么您就已经确定了您的问题。 解决方案是调整 uwsgi 参数。
作者在博文中做了什么:
CMD uwsgi -s /tmp/uwsgi.sock -w project:app --chown-socket=www-data:www-data --enable-threads & nginx -g 'daemon off;'