http的请求与响应

from flask import Flask,request

# 初始化
app = Flask(import_name=__name__)
# 编写路由视图
@app.route(rule=‘/‘)
def index():
    return "<h1>hello world!</h1>"

"""== 获取查询字符串 =="""
@app.route(rule="/args",methods=["post","get"])
def args():
    print(request.args) # 获取查询字符串
    """
    请求地址：
        http://127.0.0.1:5000/args?name=xiaoming&password=123&lve=swimming&lve=shopping
    打印效果：
        ImmutableMultiDict([(‘name‘, ‘xiaoming‘), (‘password‘, ‘123‘)])
        ImmutableMultiDict是一个由flask封装的字典类，在字典的基础上，提供了一些其他的方法而已。
        格式：
            ImmutableMultiDict([(‘键‘, ‘值‘), (‘键‘, ‘值‘)])
        字典本身不支持同名键的，ImmutableMultiDict类解决了键同名问题
        操作ImmutableMultiDict，完全可以操作字典操作，同时还提供了get，getlist方法，获取指定键的1个值或多个值    
    """
    print(request.args["name"]) # xiaoming
    print(request.args.get("name")) # xiaoming
    print(request.args.getlist("lve")) # [‘swimming‘, ‘shopping‘]

    # 把ImmutableMultiDict转换成普通字典
    print(request.args.to_dict(flat=False)) # {‘name‘: [‘xiaoming‘], ‘password‘: [‘123‘], ‘lve‘: [‘swimming‘, ‘shopping‘]}
    print(request.args.to_dict(flat=True)) # {‘name‘: ‘xiaoming‘, ‘password‘: ‘123‘, ‘lve‘: ‘swimming‘}

    return "ok"

"""== 获取请求体数据 =="""
@app.route(rule="/data",methods=["post","put","patch"])
def data():
    """接受客户端发送过来的请求体数据，是request.json,request.form,request.files等无法接受的数据，全部会保留到这里"""
    print(request.data) # 

    # 接受表单提交的数据
    print(request.form) # ImmutableMultiDict([(‘username‘, ‘root‘), (‘password‘, ‘123456‘)])

    # 接受ajax或其他客户端提交过来的json数据
    print(request.json) # {‘username‘: ‘root‘, ‘password‘: ‘123456‘}

    # 接受上传文件
    avatar = request.files["avatar"] # ImmutableMultiDict([(‘avatar‘, <FileStorage: ‘123.jpg‘ (‘image/jpeg‘)>)])
    print(avatar) # <FileStorage: ‘123.jpg‘ (‘image/jpeg‘)>


    # 获取请求头信息
    print( request.headers ) # 获取全部的而请求头信息
    print( request.headers.get("Host") )
    # 获取自定义请求头
    print( request.headers.get("company") ) # oldboy
    print( request.headers["company"] )     # oldboy
    
    # 本次请求的url地址
    print( request.url) # http://127.0.0.1:5000/data
    print( request.path ) # /data
    
    return "ok"

# 声明和加载配置
class Config():
    DEBUG = True
app.config.from_object(Config)

if __name__ == ‘__main__‘:
    # 运行flask
    app.run(host="0.0.0.0")

from flask import make_response

@app.route("/")
def index():
    # [默认支持]响应html文本
    return "<img src=‘http://flask.pocoo.org/static/logo.png‘>"
    return make_response("<h1>hello user</h1>") # 等同于上面的一段

from flask import Flask, request, jsonify
# jsonify 就是json里面的jsonify

@app.route("/")
def index():
    # 也可以响应json格式代码
    data = [
        {"id":1,"username":"liulaoshi","age":18},
        {"id":2,"username":"liulaoshi","age":17},
        {"id":3,"username":"liulaoshi","age":16},
        {"id":4,"username":"liulaoshi","age":15},
    ]
    return jsonify(data)

from flask import redirect
# 页面跳转响应
@app.route("/user")
def user():
    # 页面跳转 redirect函数就是response对象的页面跳转的封装
    # Location: http://www.baidu.com
    return redirect("http://www.baidu.com")

# 内容响应
@app.route("/")
def index():
    # [默认支持]响应html文本
    # return "<img src=‘http://flask.pocoo.org/static/logo.png‘>"

    # 也可以响应json格式代码
    data = [
        {"id":1,"username":"liulaoshi","age":18},
        {"id":2,"username":"liulaoshi","age":17},
        {"id":3,"username":"liulaoshi","age":16},
        {"id":4,"username":"liulaoshi","age":15},
    ]
    return jsonify(data)

#使用url_for可以实现视图方法之间的内部跳转
# url_for("视图方法名")
@app.route("/login")
def login():
    return redirect( url_for("index") )

# 路由传递参数
@app.route(‘/user/<user_id>‘)
def user_info(user_id):
    return ‘hello %d‘ % user_id

# 重定向
@app.route(‘/demo4‘)
def demo4():
    # 使用 url_for 生成指定视图函数所对应的 url
    return redirect( url_for(endpoint="user",user_id=100) )

@app.route(‘/demo4‘)
def demo4():
    return ‘状态码为 666‘, 400
  
"""还可以使用make_response创建Response对象，然后通过response对象返回数据"""
from flask import make_response
@app.route("/rep")
def index7():
    response = make_response("ok")
    print(response)
    response.headers["Company"] = "oldboy" # 自定义响应头
    response.status_code = 201 # 自定义响应状态码
    return response