轮询：通过setInterval向后台请求数据，更新html

from flask import Flask,render_template,request,jsonifyapp = Flask(__name__)USERS = {    '1':{
    'name':'贝贝','count':1},    '2':{
    'name':'小东北','count':0},    '3':{
    'name':'何伟明','count':0},}@app.route('/user/list')def user_list():    import time    return render_template('user_list.html',users=USERS)@app.route('/vote',methods=['POST'])def vote():    uid = request.form.get('uid')    USERS[uid]['count'] += 1    return "投票成功"@app.route('/get/vote',methods=['GET'])def get_vote():    return jsonify(USERS)if __name__ == '__main__':    # app.run(host='192.168.13.253',threaded=True)    app.run(threaded=True)

    
              
              
      
               {
     % for key,val in users.items() %}            
       
{
    {val.name}} ({
    {val.count}})
        {
     % endfor %}    
      
        

长轮询：基于时间循环和队列的请求等待，实现数据的实时更新

from flask import Flask,render_template,request,jsonify,sessionimport uuidimport queueapp = Flask(__name__)app.secret_key = 'asdfasdfasd'USERS = {    '1':{
    'name':'贝贝','count':1},    '2':{
    'name':'小东北','count':0},    '3':{
    'name':'何伟明','count':0},}QUEQUE_DICT = {    # 'asdfasdfasdfasdf':Queue()}@app.route('/user/list')def user_list():    user_uuid = str(uuid.uuid4())    QUEQUE_DICT[user_uuid] = queue.Queue()    session['current_user_uuid'] = user_uuid    return render_template('user_list.html',users=USERS)@app.route('/vote',methods=['POST'])def vote():    uid = request.form.get('uid')    USERS[uid]['count'] += 1    for q in QUEQUE_DICT.values():        q.put(USERS)    return "投票成功"@app.route('/get/vote',methods=['GET'])def get_vote():    user_uuid = session['current_user_uuid']    q = QUEQUE_DICT[user_uuid]    ret = {
    'status':True,'data':None}    try:        users = q.get(timeout=5)        ret['data'] = users    except queue.Empty:        ret['status'] = False    return jsonify(ret)if __name__ == '__main__':    app.run(host='192.168.13.253',threaded=True)    # app.run(threaded=True)

    
              
              
      
               {
     % for key,val in users.items() %}            
       
{
    {val.name}} ({
    {val.count}})
        {
     % endfor %}    
      
        

from flask import Flask,render_template,request,jsonifyapp = Flask(__name__)import queueq = queue.Queue()@app.route('/get/vote')def get_vote():    try:        val = q.get(timeout=20)    except queue.Empty:        val = "已超时"    return val@app.route('/vote')def vote():    q.put('10')    return '投票成功'if __name__ == '__main__':    # app.run(host='192.168.13.253',threaded=True)    app.run(threaded=True)