I have a Flask application that uses SocketIO to fetch data from Postgres live.
The app works fine when I run this locally.
The problem arouses when I use docker-compose to host my Flask app in a container. My JS client and flask server is hosted into a single app and on the same container.
My socketio in JS is like this:
var socket = io().connect(window.location.protocol + '//' + document.domain + ':' + location.port);
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
# Install the dependencies from requirements
RUN pip install -r requirements.txt
# Tell the port number the container should expose
EXPOSE 8083
# Run the command
ENTRYPOINT ["./entry.sh"]
entry.sh:
#!/bin/sh
gunicorn -k geventwebsocket.gunicorn.workers.GeventWebSocketWorker -b :8083 -w 5 run:app
My docker-compose is as such:
version: "3.8"
services:
fortweet:
container_name: fortweet
build: ./
env_file:
- secret.env
networks:
- plutusnet
ports:
- 8083:8083
restart: always
networks:
plutusnet:
name: plutus_network
driver: bridge
I’ve also tried to use var socket = io.connect('http://public_ip_of_website:8083') but my socket connection still doesn’t work.
How it should normally work is when i run this locally and click a certain button, it executes this function in my JS:
$("#tweets-live-start").click(function(){
if (is_streaming == true){
alert("A stream is already running")
}else{
$.ajax({
type: "POST",
url : "/admin/startstream",
data: {url : "print \"hello\""},
contentType: 'application/json;charset=UTF-8'
});
}
});
When my server gets the hello, it starts a tweet streaming and emits them through the socket. Then my socket captures them as such:
// 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>
`);
});
But when i run it on docker, nothing happens.
When i check my browser JS console, it seems that it is polling with a bad request and i don’t know why:
index.js:83 GET http://th3pl4gu3.com:8083/socket.io/?EIO=3&transport=polling&t=NPYYrxr 400 (BAD REQUEST)
Here is my docker ps for more info:
46446efeb472 mervin16/fortweet:dev "/bin/bash entry.sh" About a minute ago Up About a minute 0.0.0.0:8083->8083/tcp fortweet
12b2bff36af0 postgres "docker-entrypoint.s…" 2 hours ago Up 2 hours 0.0.0.0:5432->5432/tcp plutus
I don’t think this is an accessibility issue because i tried several telnet tests from each container and to each container also.
I checked logs of the docker container and it gives this:
fortweet | [2020-12-26 15:18:55 +0000] [8] [INFO] Starting gunicorn 20.0.4
fortweet | [2020-12-26 15:18:55 +0000] [8] [INFO] Listening at: http://0.0.0.0:8083 (8)
fortweet | [2020-12-26 15:18:55 +0000] [8] [INFO] Using worker: geventwebsocket.gunicorn.workers.GeventWebSocketWorker
fortweet | [2020-12-26 15:18:55 +0000] [11] [INFO] Booting worker with pid: 11
fortweet | [2020-12-26 15:18:55 +0000] [12] [INFO] Booting worker with pid: 12
fortweet | [2020-12-26 15:18:55 +0000] [13] [INFO] Booting worker with pid: 13
fortweet | [2020-12-26 15:18:55 +0000] [14] [INFO] Booting worker with pid: 14
fortweet | [2020-12-26 15:18:55 +0000] [15] [INFO] Booting worker with pid: 15
fortweet | The client is using an unsupported version of the Socket.IO or Engine.IO protocols (further occurrences of this error will be logged with level INFO)
fortweet | The client is using an unsupported version of the Socket.IO or Engine.IO protocols (further occurrences of this error will be logged with level INFO)
fortweet | 172.16.0.1 - - [2020-12-26 15:19:57] "POST /admin/startstream HTTP/1.1" 204 170 0.023672
fortweet | The client is using an unsupported version of the Socket.IO or Engine.IO protocols (further occurrences of this error will be logged with level INFO)
fortweet | The client is using an unsupported version of the Socket.IO or Engine.IO protocols (further occurrences of this error will be logged with level INFO)
fortweet | 172.16.0.1 - - [2020-12-26 15:20:20] "GET /socket.io/?EIO=3&transport=polling&t=1608996021267-7 HTTP/1.1" 400 195 0.001418
fortweet | 172.16.0.1 - - [2020-12-26 15:20:20] "GET /socket.io/?EIO=3&transport=polling&t=1608996021267-7 HTTP/1.1" 400 195 0.001418
fortweet | 172.16.0.1 - - [2020-12-26 15:20:21] "GET /socket.io/?EIO=3&transport=polling&t=1608996021395-8 HTTP/1.1" 400 195 0.001625
fortweet | 172.16.0.1 - - [2020-12-26 15:20:21] "GET /socket.io/?EIO=3&transport=polling&t=1608996021395-8 HTTP/1.1" 400 195 0.001625
fortweet | 172.16.0.1 - - [2020-12-26 15:20:26] "GET /socket.io/?EIO=3&transport=polling&t=1608996026417-9 HTTP/1.1" 400 195 0.001367
fortweet | 172.16.0.1 - - [2020-12-26 15:20:26] "GET /socket.io/?EIO=3&transport=polling&t=1608996026417-9 HTTP/1.1" 400 195 0.001367
fortweet | 172.16.0.1 - - [2020-12-26 15:20:26] "GET /socket.io/?EIO=3&transport=polling&t=1608996027270-8 HTTP/1.1" 400 195 0.003811
fortweet | 172.16.0.1 - - [2020-12-26 15:20:26] "GET /socket.io/?EIO=3&transport=polling&t=1608996027270-8 HTTP/1.1" 400 195 0.003811
fortweet | 172.16.0.1 - - [2020-12-26 15:20:34] "POST /admin/startstream HTTP/1.1" 204 170 0.015831
fortweet | 172.16.0.1 - - [2020-12-26 15:20:36] "GET /socket.io/?EIO=3&transport=polling&t=1608996036486-11 HTTP/1.1" 400 195 0.001096
Can anyone please help me ?