python flask server 接收post数据注意

前面写了两篇文章，结果错误不少，经过修正，改了很多错误

1 跨域

加上以下两条

from flask_cors import CORS
from flask_cors import cross_origin

以下让整个全景跨域

CORS(app, supports_credentials=True)

2 secret_key

加上secret_key 防止session 报错

app.secret_key='kdjklfjkd87384hjdhjh'

3 接收python 数据

@app.route('/project/add', methods=['POST'])
def add_entry():
    #if not session.get('logged_in'):
    #    abort(401)
    print("data recv !!!!!!!!!!!!!!!!!!!!!!")
    data=request.get_data()
    print("data recv 2!!!!!!!!!!!!!!!!!!!!!!")
    data = data.decode('utf-8')
    data=json.loads(data)
    print("data recv 3!!!!!!!!!!!!!!!!!!!!!!")
    pname = data.get('projectname')
    num= data.get('projectname')
    memo = data.get('memo')
    g.db.execute('insert into project(projectname,picnum,memo) values (?,?,?)',
    #             [request.form['projectname'], request.form['picnum'],request.form['memo'] ])
                  [pname,num,memo])
    g.db.commit()
    flash('New project was successfully posted')
    return "{'ret':ok}"

其中需要data.decode 去解码utf-8 编码，去掉前面的 b 这个多余的字节。

4 改成非develop

去掉flask develop的警告

    server = pywsgi.WSGIServer(('0.0.0.0', 5000), app)
    server.serve_forever()

这样要把gevent装上
pip install gevent

5 发送端测试

发送端使用以前的代码,注意的是：发送的时候写上 json = data，不要写成 data = data，以前我的写法是错误的。

import json
import requests
import time
headers = {'Content-Type': 'application/json'}
data = {
    "projectname":"four screen",
    "picnum":8,
    "memo":"test"
}
try:
	r = requests.post("http://127.0.0.1:5000/project/add", json=data, headers=headers)
	print(r.text)
except requests.exceptions.ConnectionError:
	print('connectionError')	
time.sleep(1)

6 代码清单

以下代码清单错误减去了不少，数据库增加数据正常

服务端和测试客户端正常

from __future__ import with_statement
from contextlib import closing  
import sqlite3
from flask import Flask, request, session, g, redirect, url_for, \
   abort, render_template, flash,jsonify
from flask_cors import CORS
from flask_cors import cross_origin
import json
from gevent import pywsgi
# configuration
DATABASE = './project.db'
DEBUG = True



app = Flask(__name__)
app.config.from_object(__name__)

app.config.from_envvar('FLASKR_SETTINGS', silent=True)
app.secret_key='kdjklfjkd87384hjdhjh'

CORS(app, supports_credentials=True)
def connect_db():
   return sqlite3.connect(app.config['DATABASE'])


def init_db():
   with closing(connect_db()) as db:
       with app.open_resource('db.sql',"r") as f:
           #str = f.read()
           #print(str)
           db.cursor().executescript(f.read())
       db.commit()


@app.before_request
def before_request():
   g.db = connect_db()


@app.after_request
def after_request(response):
   g.db.close()
   return response


@app.route('/')
def show_first():
   return "this is a test"

@app.route('/project', methods=['GET'])
def show_project():
   cur = g.db.execute('select id,projectname,picnum,memo,created from project order by id desc')

   entries = [dict(id=row[0], projectname=row[1],picnum= row[2],memo=row[3],created=row[4]) for row in cur.fetchall()]
   return jsonify(entries)

@app.route('/project/add', methods=['POST'])
def add_entry():
   #if not session.get('logged_in'):
   #    abort(401)
   print("data recv !!!!!!!!!!!!!!!!!!!!!!")
   data=request.get_data()
   print("data recv 2!!!!!!!!!!!!!!!!!!!!!!")
   #get_Data = get_Data.decode('utf-8')
   data = data.decode('utf-8')
   data=json.loads(data)
   print("data recv 3!!!!!!!!!!!!!!!!!!!!!!")
   pname = data.get('projectname')
   num= data.get('projectname')
   memo = data.get('memo')
   g.db.execute('insert into project(projectname,picnum,memo) values (?,?,?)',
   #             [request.form['projectname'], request.form['picnum'],request.form['memo'] ])
                 [pname,num,memo])
   g.db.commit()
   flash('New project was successfully posted')
   return "{'ret':ok}"
   #return redirect(url_for('show_first'))


@app.route('/project/del/', methods=['POST'])
#@cross_origin(supports_credentials=True)
def del_entry():
   #if not session.get('logged_in'):
   #    abort(401)
   g.db.execute('delete from project where id = ?',[id])
   g.db.commit()
   flash('project was successfully delete')
   return redirect(url_for('show_first'))


#需要登录或者单点登录的时候把以下代码准备加上
@app.route('/login', methods=['GET', 'POST'])
def login():
   error = None
   if request.method == 'POST':
       if request.form['username'] != app.config['USERNAME']:
           error = 'Invalid username'
       elif request.form['password'] != app.config['PASSWORD']:
           error = 'Invalid password'
       else:
           session['logged_in'] = True
           flash('You were logged in')
           return redirect(url_for('show_first'))
   return render_template('login.html', error=error)

 #需要登录或者单点登录的时候把以下代码准备加上
@app.route('/logout')
def logout():
   session.pop('logged_in', None)
   flash('You were logged out')
   return redirect(url_for('show_first'))


if __name__ == '__main__':
   init_db()
   server = pywsgi.WSGIServer(('0.0.0.0', 5000), app)
   server.serve_forever()