В настоящее время я пытаюсь успешно построить гистограмму, когда результаты из фрейма данных обновляются или когда в данных есть какие-либо изменения.
Настройка:
- Flask-SocketIO==4.3.1
- python-engineio == 3.13.2
- Python-сокетио == 4.6.0
Убедитесь, что вы перезагрузили компьютер, чтобы не столкнуться с ошибками.
Код Python, сохраненный в папке D:\Projects\test_backgroundtask:
from flask import Flask, render_template, request
import pandas as pd
from flask_executor import Executor
import plotly
import plotly.graph_objs as go
from flask_socketio import SocketIO, emit
import json
global test_val
app = Flask(__name__)
socketio = SocketIO(app)
def create_plot(feature_importance):
feature_importance=feature_importance.reset_index(drop=True)
feature_importance=feature_importance.iloc[0:5]
print(feature_importance)
data = [
go.Bar(
x=feature_importance['Age'], # assign x as the dataframe column 'x'
y=feature_importance['Name'], orientation='h'
)
]
graphJSON = json.dumps(data, cls=plotly.utils.PlotlyJSONEncoder)
return graphJSON
@socketio.on("response")
def background_task_func():
global test_val
global plot
socketio.sleep(10)
data = {'Name': ['Tom', 'Joseph', 'Krish', 'John'], 'Age': [20, 21, 19, 18]}
test_val= pd.DataFrame(data)
bar = create_plot(test_val)
plot=bar
if test_val.shape[0]>1:
print(test_val)
emit('response_output',plot ,broadcast=True)
socketio.sleep(1)
#return render_template('views/index_img_soc.html', plot=bar)
@app.route('/', methods=['GET'])
def index():
global plot
executor.submit(background_task_func)
bar = create_plot(test_val)
return render_template('views/index_img_soc.html', plot=bar)
if __name__ == "__main__":
data ={'Name': [], 'Age': []}
test_val= pd.DataFrame(data)
executor = Executor(app)
socketio.run(app)
Html-код (сохраненный в D:\Projects\test_backgroundtask\template\views):
<script src="https://cdn.plot.ly/plotly-latest.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.6/d3.min.js"></script>
<div class="chart" id="bargraph">
<script src="//cdnjs.cloudflare.com/ajax/libs/socket.io/2.2.0/socket.io.js" integrity="sha256-yr4fRk/GU1ehYJPAs8P4JlTgu0Hdsp4ZKrx8bDEDC3I=" crossorigin="anonymous"></script>
<script type="text/javascript" charset="utf-8">
var socket = io().connect('http://127.0.0.1:5000');
socket.emit('response')
socket.on('response_output', function(receiving_data) {
var graphs = {{plot | safe}};
Plotly.plot('bargraph',graphs,{});
});
</script>
</div>
Вывод:
WebSocket transport not available. Install eventlet or gevent and gevent-websocket for improved performance.
* Serving Flask app "flask_background_app_img_soc2" (lazy loading)
* Environment: production
WARNING: This is a development server. Do not use it in a production deployment.
Use a production WSGI server instead.
* Debug mode: off
* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
127.0.0.1 - - [14/Jul/2021 11:45:01] "GET / HTTP/1.1" 200 -
Empty DataFrame
Columns: [Name, Age]
Index: []
2c6e85bb23aa4c83af37bc005a08837b: Sending packet OPEN data {'sid': '2c6e85bb23aa4c83af37bc005a08837b', 'upgrades': [], 'pingTimeout': 60000, 'pingInterval': 25000}
2c6e85bb23aa4c83af37bc005a08837b: Sending packet MESSAGE data 0
127.0.0.1 - - [14/Jul/2021 11:45:03] "GET /socket.io/?EIO=3&transport=polling&t=NgaPyfS HTTP/1.1" 200 -
2c6e85bb23aa4c83af37bc005a08837b: Received packet MESSAGE data 2["response"]
received event "response" from 2c6e85bb23aa4c83af37bc005a08837b [/]
127.0.0.1 - - [14/Jul/2021 11:45:03] "POST /socket.io/?EIO=3&transport=polling&t=NgaPyf-&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
Name Age
0 Tom 20
1 Joseph 21
2 Krish 19
3 John 18
Name Age
0 Tom 20
1 Joseph 21
2 Krish 19
3 John 18
emitting event "response_output" to all [/]
2c6e85bb23aa4c83af37bc005a08837b: Sending packet MESSAGE data 2["response_output","[{\"orientation\": \"h\", \"x\": [20, 21, 19, 18], \"y\": [\"Tom\", \"Joseph\", \"Krish\", \"John\"], \"type\": \"bar\"}]"]
127.0.0.1 - - [14/Jul/2021 11:45:13] "GET /socket.io/?EIO=3&transport=polling&t=NgaPyg0&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
Name Age
0 Tom 20
1 Joseph 21
2 Krish 19
3 John 18
Name Age
0 Tom 20
1 Joseph 21
2 Krish 19
3 John 18
2c6e85bb23aa4c83af37bc005a08837b: Received packet PING data None
2c6e85bb23aa4c83af37bc005a08837b: Sending packet PONG data None
127.0.0.1 - - [14/Jul/2021 11:45:28] "GET /socket.io/?EIO=3&transport=polling&t=NgaP_9E&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
127.0.0.1 - - [14/Jul/2021 11:45:28] "POST /socket.io/?EIO=3&transport=polling&t=NgaQ2md&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
2c6e85bb23aa4c83af37bc005a08837b: Received packet PING data None
2c6e85bb23aa4c83af37bc005a08837b: Sending packet PONG data None
127.0.0.1 - - [14/Jul/2021 11:45:54] "GET /socket.io/?EIO=3&transport=polling&t=NgaQ2nA&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
127.0.0.1 - - [14/Jul/2021 11:45:54] "POST /socket.io/?EIO=3&transport=polling&t=NgaQ93n&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
2c6e85bb23aa4c83af37bc005a08837b: Received packet PING data None
2c6e85bb23aa4c83af37bc005a08837b: Sending packet PONG data None
127.0.0.1 - - [14/Jul/2021 11:46:20] "GET /socket.io/?EIO=3&transport=polling&t=NgaQ94a&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
127.0.0.1 - - [14/Jul/2021 11:46:20] "POST /socket.io/?EIO=3&transport=polling&t=NgaQFPv&sid=2c6e85bb23aa4c83af37bc005a08837b HTTP/1.1" 200 -
Первый вывод, даже если фрейм данных обновлен. 
После перезагрузки страницы страница пуста, а затем отображается правильная диаграмма. 
Чего я хотел бы достичь:
- Автоматически отображать гистограмму при обновлении фрейма данных без перезагрузки страницы.
