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
liumiaocn:flask liumiao$ which flask/usr/local/bin/flaskliumiaocn:flask liumiao$ flask --versionFlask 1.0.2Python 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/pythonfrom flask import Flaskfrom flask import render_templateapp = 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
代码示例：HTTP谓词（DELETE|PUT|POST）
liumiaocn:flask liumiao$ cat flask_4.py #!/usr/bin/pythonfrom flask import Flaskfrom flask import render_templatefrom flask import requestimport jsonapp = 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轮子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VEVB武林网的支持。
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