Python编程在flask中模拟进行Restful的CRUD操作

程序员文章站 2022-07-06 11:54:03

这篇文章中我们将通过对helloworld的message进行操作，介绍一下如何使用flask进行restful的crud。概要信息事前准备：flask...

这篇文章中我们将通过对helloworld的message进行操作，介绍一下如何使用flask进行restful的crud。

事前准备：flask

liumiaocn:flask liumiao$ which flask
/usr/local/bin/flask
liumiaocn:flask liumiao$ flask --version
flask 1.0.2
python 2.7.10 (default, jul 15 2017, 17:16:57) 
[gcc 4.2.1 compatible apple llvm 9.0.0 (clang-900.0.31)]
liumiaocn:flask liumiao$

代码示例：http谓词（get）

就像angular的插值表达式在模版中的作用一样，在flask中也可以一样使用，如果不熟悉angular的插值表达式的话也不要紧，看完下面的例子，基本上就会有一个大致的印象。

代码示例

liumiaocn:flask liumiao$ cat flask_4.py 
#!/usr/bin/python
from flask import flask
from flask import render_template
app = flask(__name__)
greeting_messages=["hello world", "hello python"]
@app.route("/api/messages",methods=['get'])
def get_messages():
  return render_template("resttest.html",messages=greeting_messages) 
if __name__ == "__main__":
  app.debug=true
  app.run(host='0.0.0.0',port=7000)
liumiaocn:flask liumiao$

模版文件

liumiaocn:flask liumiao$ cat templates/resttest.html 
<!doctype html>
<html>
<head>
 <meta charset="utf-8">
 <title>hello restful</title>
</head>
<body>
    {% for message in messages %}
 <h1>{{ message }}</h1>
    {% endfor %}
</body>
</html>
liumiaocn:flask liumiao$

代码解析：app.route中指定了http谓词get，缺省get可以省略，如果一个方法对应多个谓词动作，通过request.method来分离时，可以写成methods=[‘get','post']的形式

执行&确认

liumiaocn:flask liumiao$ ./flask_4.py 
 * serving flask app "flask_4" (lazy loading)
 * environment: production
  warning: do not use the development server in a production environment.
  use a production wsgi server instead.
 * debug mode: on
 * running on http://0.0.0.0:7000/ (press ctrl+c to quit)
 * restarting with stat
 * debugger is active!
 * debugger pin: 131-533-062

页面确认

Python编程在flask中模拟进行Restful的CRUD操作

代码示例：http谓词（delete|put|post）

liumiaocn:flask liumiao$ cat flask_4.py 
#!/usr/bin/python
from flask import flask
from flask import render_template
from flask import request
import json
app = flask(__name__)
greeting_messages=["hello world", "hello python"]
#http: get: retrieve operation
@app.route("/api/messages",methods=['get'])
def get_messages():
  return render_template("resttest.html",messages=greeting_messages) 
#http: delete: delete operation
@app.route("/api/messages/<messageid>",methods=['delete'])
def delete_message(messageid):
  global greeting_messages
  del greeting_messages[int(messageid)]
  return render_template("resttest.html",messages=greeting_messages) 
#http: put: update operation
#http: post: create operation
@app.route("/api/messages/<messageid>",methods=['put','post'])
def update_message(messageid):
  global greeting_message
  msg_info=json.loads(request.get_data(true,true,false))
  #msg_info=request.args.get('message_info')
  #msg_info=request.form.get('message_info','default value')
  #msg_info=request.values.get('message_info','hello...')
  greeting_messages.append("hello " + msg_info["message_info"])
  return render_template("resttest.html",messages=greeting_messages) 
if __name__ == "__main__":
  app.debug=true
  app.run(host='0.0.0.0',port=7000)
liumiaocn:flask liumiao$

执行&结果确认

执行日志

liumiaocn:flask liumiao$ ./flask_4.py 
 * serving flask app "flask_4" (lazy loading)
 * environment: production
  warning: do not use the development server in a production environment.
  use a production wsgi server instead.
 * debug mode: on
 * running on http://0.0.0.0:7000/ (press ctrl+c to quit)
 * restarting with stat
 * debugger is active!
 * debugger pin: 131-533-062

结果确认：delete

liumiaocn:flask liumiao$ curl -x delete http://localhost:7000/api/messages/1
<!doctype html>
<html>
<head>
  <meta charset="utf-8">
  <title>hello restful</title>
</head>
<body>
  <h1>hello world</h1>
</body>
</html>liumiaocn:flask liumiao$

可以看到执行一次delete之后，两条消息现在只剩下一条消息了，接下来使用post添加再添加一条

liumiaocn:flask liumiao$ curl -x post -d '{"message_info":"liumiaopost"}' http://localhost:7000/api/messages/3
<!doctype html>
<html>
<head>
  <meta charset="utf-8">
  <title>hello restful</title>
</head>
<body>
  <h1>hello world</h1>
  <h1>hello liumiaopost</h1>
</body>
</html>liumiaocn:flask liumiao$

再执行一次put操作

liumiaocn:flask liumiao$ curl -x put -d '{"message_info":"liumiaoput"}' http://localhost:7000/api/messages/4
<!doctype html>
<html>
<head>
  <meta charset="utf-8">
  <title>hello restful</title>
</head>
<body>
  <h1>hello world</h1>
  <h1>hello liumiaopost</h1>
  <h1>hello liumiaoput</h1>
</body>
</html>liumiaocn:flask liumiao$

小结

这篇文章中，使用最简单的方式在flask中模拟了一下如何进行restful的crud操作，当然，实际的做法有很多种，在接下来的文章中还会介绍另外一种非常常见的*flask-restful.

总结

以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作具有一定的参考学习价值，谢谢大家对的支持。如果你想了解更多相关内容请查看下面相关链接

上一篇：关于破解邮箱的一点心得

下一篇：基于Python在MacOS上安装robotframework-ride