使用 Django Channels 向所有连接的客户端发送信息
Using Django Channels to send info to all connected clients
我正在创建一个系统,其中 Twitter Live Streaming API 通过给定的关键字获取实时的推文数据流。每当推文出现时,我都想通过 WebSockets(使用 Django Channels)将新数据发送到所有连接的客户端。这是我目前的程序:
- Twitter 直播代码在获取新数据时调用 consumers.py 中的
initiateHandshake()
函数
- Django 通道将文本 "handshake" 发送给所有客户端
- 客户端收到握手消息并发回消息
- websocket.recieve 函数获取此消息,并根据存储在客户端连接会话中的过滤器信息,发回所需的数据(这就是需要握手的原因 - 因为每个客户端都有它自己的过滤器在其连接会话中)
现在,问题是 initiateHandshake()
中的 "handshake" 消息没有发送。为什么会这样,我该如何解决?太感谢了!我的代码如下。
WebSockets 运行正常(如果客户端发送消息,我可以使用 reply_channel 回复它 - 一切正常)
routing.py
from channels.routing import route
from tweetrunner.consumers import *
channel_routing = [
route("websocket.connect", ws_connect),
route("websocket.receive", ws_message),
route("websocket.disconnect", ws_disconnect),
]
consumers.py
# In consumers.py
from channels import Group, Channel
from channels.sessions import channel_session
from .models import InputTweet
from django.shortcuts import render
# Outside world connection
def initiateHandshake():
Group("table").send({"text": "handshake"})
# Connected to websocket.connect
@channel_session
def ws_connect(message):
# Accept connection
message.reply_channel.send({"accept": True})
message.channel_session["sort"] = "none"
# Add to group
Group("table").add(message.reply_channel)
# Connected to websocket.receive
@channel_session
def ws_message(message):
definition = message.content['text'][:1]
if definition == "1":
emotion = message.content['text'][1:]
message.channel_session["sort"] = message.content['text'][1:]
sendback = ""
if emotion == 'none':
given_tweets = InputTweet.objects.all()
given_tweets = given_tweets[(len(given_tweets) - 1250):]
print("before render")
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("rendered")
else:
given_tweets = InputTweet.objects.filter(emotion__startswith=emotion).order_by('score')
given_tweets = given_tweets[(len(given_tweets) - 1250):]
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("about to send")
message.reply_channel.send({
"text": sendback.content.decode('utf-8'),
})
print("sent -- END CONNECTION LOGS")
elif definition == "3":
print("Keep alive!")
else:
emotion = message.channel_session["sort"]
sendback = ""
print("entered 2")
if emotion == 'none':
given_tweets = InputTweet.objects.all()
given_tweets = given_tweets[(len(given_tweets) - 1250):]
print("before render")
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("rendered")
else:
given_tweets = InputTweet.objects.filter(emotion__startswith=emotion).order_by('score')
given_tweets = given_tweets[(len(given_tweets) - 1250):]
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("about to send")
#content = sendback.read()
message.reply_channel.send({
"text": sendback.content.decode('utf-8'),
})
print("sent -- END CONNECTION LOGS")
# Connected to websocket.disconnect
@channel_session
def ws_disconnect(message):
Group("table").discard(message.reply_channel)
我的代码不在任何 django 应用程序中,正在像这样初始化 django(我可以访问数据库并使用 django 调用,所以它可以工作):
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "analyticsui.settings")
import django
django.setup()
JavaScript 客户端:
socket = new WebSocket("ws://" + window.location.host + "/");
socket.onmessage = function(e) {
alert("Got message: " + e.data)
if (e.data == "handshake") {
socket.send("2handshake");
alert("sent");
} else {
document.getElementById("tweetTable").innerHTML = e.data;
$('.tooltiphere').tooltip('remove');
$('.tooltiphere').tooltip({delay: 10});
}
}
initiateHandshake()
使用 In-memory Channel 层时不会发送任何消息。
From the doc: In-Memory layer does not support cross-process communication
请特别使用其他通道层类型<a href="https://channels.readthedocs.io/en/stable/backends.html#redis" rel="nofollow noreferrer">Redis channel layer</a>
。一切都会按预期进行。
我正在创建一个系统,其中 Twitter Live Streaming API 通过给定的关键字获取实时的推文数据流。每当推文出现时,我都想通过 WebSockets(使用 Django Channels)将新数据发送到所有连接的客户端。这是我目前的程序:
- Twitter 直播代码在获取新数据时调用 consumers.py 中的
initiateHandshake()
函数 - Django 通道将文本 "handshake" 发送给所有客户端
- 客户端收到握手消息并发回消息
- websocket.recieve 函数获取此消息,并根据存储在客户端连接会话中的过滤器信息,发回所需的数据(这就是需要握手的原因 - 因为每个客户端都有它自己的过滤器在其连接会话中)
现在,问题是 initiateHandshake()
中的 "handshake" 消息没有发送。为什么会这样,我该如何解决?太感谢了!我的代码如下。
WebSockets 运行正常(如果客户端发送消息,我可以使用 reply_channel 回复它 - 一切正常)
routing.py
from channels.routing import route
from tweetrunner.consumers import *
channel_routing = [
route("websocket.connect", ws_connect),
route("websocket.receive", ws_message),
route("websocket.disconnect", ws_disconnect),
]
consumers.py
# In consumers.py
from channels import Group, Channel
from channels.sessions import channel_session
from .models import InputTweet
from django.shortcuts import render
# Outside world connection
def initiateHandshake():
Group("table").send({"text": "handshake"})
# Connected to websocket.connect
@channel_session
def ws_connect(message):
# Accept connection
message.reply_channel.send({"accept": True})
message.channel_session["sort"] = "none"
# Add to group
Group("table").add(message.reply_channel)
# Connected to websocket.receive
@channel_session
def ws_message(message):
definition = message.content['text'][:1]
if definition == "1":
emotion = message.content['text'][1:]
message.channel_session["sort"] = message.content['text'][1:]
sendback = ""
if emotion == 'none':
given_tweets = InputTweet.objects.all()
given_tweets = given_tweets[(len(given_tweets) - 1250):]
print("before render")
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("rendered")
else:
given_tweets = InputTweet.objects.filter(emotion__startswith=emotion).order_by('score')
given_tweets = given_tweets[(len(given_tweets) - 1250):]
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("about to send")
message.reply_channel.send({
"text": sendback.content.decode('utf-8'),
})
print("sent -- END CONNECTION LOGS")
elif definition == "3":
print("Keep alive!")
else:
emotion = message.channel_session["sort"]
sendback = ""
print("entered 2")
if emotion == 'none':
given_tweets = InputTweet.objects.all()
given_tweets = given_tweets[(len(given_tweets) - 1250):]
print("before render")
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("rendered")
else:
given_tweets = InputTweet.objects.filter(emotion__startswith=emotion).order_by('score')
given_tweets = given_tweets[(len(given_tweets) - 1250):]
sendback = render(None, 'tweetrunner/get_table_update.html', {'given_tweets': given_tweets})
print("about to send")
#content = sendback.read()
message.reply_channel.send({
"text": sendback.content.decode('utf-8'),
})
print("sent -- END CONNECTION LOGS")
# Connected to websocket.disconnect
@channel_session
def ws_disconnect(message):
Group("table").discard(message.reply_channel)
我的代码不在任何 django 应用程序中,正在像这样初始化 django(我可以访问数据库并使用 django 调用,所以它可以工作):
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "analyticsui.settings")
import django
django.setup()
JavaScript 客户端:
socket = new WebSocket("ws://" + window.location.host + "/");
socket.onmessage = function(e) {
alert("Got message: " + e.data)
if (e.data == "handshake") {
socket.send("2handshake");
alert("sent");
} else {
document.getElementById("tweetTable").innerHTML = e.data;
$('.tooltiphere').tooltip('remove');
$('.tooltiphere').tooltip({delay: 10});
}
}
initiateHandshake()
使用 In-memory Channel 层时不会发送任何消息。
From the doc: In-Memory layer does not support cross-process communication
请特别使用其他通道层类型<a href="https://channels.readthedocs.io/en/stable/backends.html#redis" rel="nofollow noreferrer">Redis channel layer</a>
。一切都会按预期进行。