Python发送Post请求及解析响应结果
一、Post请求
1、使用python发送一个Post请求
有时候遇到请求url中有很多参数。
1.1 示例1
accounts和pwd请到http://shop-xo.hctestedu.com/注册。
import requests
# 请求体
data = {
"accounts": "xx",
"pwd": "xxx",
"type": "username"
}
# 只有php项目需要application和application_client_type
# 写法一, 在请求Url中带上所有参数，application和application_client_type，用&隔开
response = requests.post(url="http://shop-xo.hctestedu.com/index.php?"
"s=api/user/login"
"&application=app"
"&applicaiton_client_type=weixin", json=data)
# 输出响应结果
print(response.text)
执行结果：
{"msg":"登录成功","code":0,"data":{"id":"7073","username":"xx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"189","locking_integral":"0","referrer":"0","add_time":"1646195490","add_time_text":"2022-03-02 12:31:30","mobile_security":"","email_security":"","user_name_view":"xx","is_mandatory_bind_mobile":0,"token":"xxxxxx"}}
1.2 示例2
使用不定长参数 params，将url中需要的参数单独封装。
import requests
# 请求体
data = {
"accounts": "xx",
"pwd": "xxx",
"type": "username"
}
# 使用不定长参数params
param_data = {
"application": "app",
"application_client_type": "weixin"
}
# 写法2：使用不定长参数params
response = requests.post(url="http://shop-xo.hctestedu.com/index.php?"
"s=api/user/login", params=param_data, json=data)
# 输出响应结果
print(response.text)
执行结果：
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xx","is_mandatory_bind_mobile":0,"token":"xxxxx"}}
二、获取Response body
1、response.text
用type(）查看response.text的类型，是str
import requests
# 请求体
data = {
"accounts": "xx",
"pwd": "xxx",
"type": "username"
}
# 使用不定长参数params
param_data = {
"application": "app",
"application_client_type": "weixin"
}
# 写法2：使用不定长参数params
response = requests.post(url="http://shop-xo.hctestedu.com/index.php?"
"s=api/user/login", params=param_data, json=data)
# 输出响应结果
print(response.text)
print(type(response.text))
执行结果：
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xx","is_mandatory_bind_mobile":0,"token":"xxxxx"}}
2、response.json()
用type(）查看response.json()的类型，是dict
import requests
# 请求体
data = {
"accounts": "xx",
"pwd": "xxx",
"type": "username"
}
# 使用不定长参数params
param_data = {
"application": "app",
"application_client_type": "weixin"
}
# 写法2：使用不定长参数params
response = requests.post(url="http://shop-xo.hctestedu.com/index.php?"
"s=api/user/login", params=param_data, json=data)
# 输出响应结果
print(response.json())
print(type(response.json()))
执行结果：
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xx","is_mandatory_bind_mobile":0,"token":"xxxxx"}}
三、获取响应状态码：res.status_code
print(response.status_code)
执行结果：
200
更多状态码：
状态代码有三位数字组成，第一个数字定义了响应的类别，共分五种类别:
1xx：指示信息--表示请求已接收，继续处理
2xx：成功--表示请求已被成功接收、理解、接受
3xx：重定向--要完成请求必须进行更进一步的操作
4xx：客户端错误--请求有语法错误或请求无法实现
5xx：服务器端错误--服务器未能实现合法的请求
常见状态码：
200 OK //客户端请求成功
400 Bad Request //客户端请求有语法错误，不能被服务器所理解
401 Unauthorized //请求未经授权，这个状态代码必须和WWW-Authenticate报头域一起使用
403 Forbidden //服务器收到请求，但是拒绝提供服务
404 Not Found //请求资源不存在，eg：输入了错误的URL
500 Internal Server Error //服务器发生不可预期的错误
503 Server Unavailable //服务器当前不能处理客户端的请求，一段时间后可能恢复正常
四、获取响应cookies：res.cookies
print(response.cookies)
执行结果：
五、获取响应headers：res.headers
print(response.headers)
执行结果：
{'Server': 'nginx', 'Date': 'Sun, 05 Mar 2023 10:04:02 GMT', 'Content-Type': 'application/json; charset=utf-8', 'Transfer-Encoding': 'chunked', 'Connection': 'keep-alive', 'Set-Cookie': 'PHPSESSID=ul9qsgallg17d5am81q08pfhj0; path=/; HttpOnly', 'Expires': 'Thu, 19 Nov 1981 08:52:00 GMT', 'Cache-Control': 'no-store, no-cache, must-revalidate', 'Pragma': 'no-cache'}
六、获取响应结果原始内容：res.content
content，没有经过编译的，以字节的形式展示。而上述提到的text是编译过的。自动找到请求头中的编码格式，进行解析。
print(response.content)
print(type(response.content))
执行结果：
b'{"msg":"\xe7\x99\xbb\xe5\xbd\x95\xe6\x88\x90\xe5\x8a\x9f","code":0,"data":{"id":"22299","username":"xxxxx","nickname":"","mobile":"","email":"","avatar":"http:\\/\\/shop-xo.hctestedu.com\\/static\\/index\\/default\\/images\\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xxxxx","is_mandatory_bind_mobile":0,"token":"d653d78ac417f65e1cd38c6f3e220341"}}'
content还支持手动的编码，例如使用utf-8编码，编码后的是str类型，json本质是一种字符串类型
resp = response.content.decode("utf-8")
print(resp)
print(type(resp))
执行结果：
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xxxxx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xxxxx","is_mandatory_bind_mobile":0,"token":"d653d78ac417f65e1cd38c6f3e220341"}}
七、获取响应结果：最原生的状态，对象在内存中的地址：res.raw
print(response.raw)
print(type(response.raw))
执行结果：
八、解析响应数据
响应数据如下：
{
"msg": "登录成功",
"code": 0,
"data": {
"id": "22299",
"username": "Summer",
"nickname": "",
"mobile": "",
"email": "",
"avatar": "http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg",
"alipay_openid": "",
"weixin_openid": "",
"weixin_unionid": "",
"weixin_web_openid": "",
"baidu_openid": "",
"toutiao_openid": "",
"qq_openid": "",
"qq_unionid": "",
"integral": "0",
"locking_integral": "0",
"referrer": "0",
"add_time": "1678005098",
"add_time_text": "2023-03-05 16:31:38",
"mobile_security": "",
"email_security": "",
"user_name_view": "chengcheng",
"is_mandatory_bind_mobile": 0,
"token": "d653d78ac417f65e1cd38c6f3e220341"
}
}
通常我们获取响应数据后，是需要进行结果验证的。例如，我想从登录接口的响应中拿到token，供后面的接口请求鉴权使用。
1、字典方式解析及其缺点
上面已经讲到，可以使用response.json()方法拿到一个字典。既然是字典，就可以用处理字典的方式来获取某个字段的值。
resp = response.json()
token = resp["data"]["token"]
print(token )
执行结果：
d653d78ac417f65e1cd38c6f3e220341
字典解析的缺点：如果接口数据异常，响应体缺少某个字段，就会发生keyerror，导致程序异常。
resp = response.json()
token = resp["data"]["token1"]
print(token )
执行结果：
Traceback (most recent call last):
File "E:\Coding\python-workspace\Interface_test\first_requests.py", line 128, in
token = resp["data"]["token1"]
KeyError: 'token1'
2、Jsonpath表达式解析及其优点
上面的响应body结构比较简单，如果我们要解析特别复杂的响应体，通过字典方式就很复杂。这个时候更推荐jsonpath。需要引入jsonpath库。
import jsonpath
resp = response.json() # 将返回值转换成字典格式
token = jsonpath.jsonpath(resp, '$..token') # token的jsonpath表达式：$..token
print(token)
执行结果：
['d653d78ac417f65e1cd38c6f3e220341']
通过结果来看，获取到的token是只有一个元素的列表。我们要想拿到token通过下标访问。
修改上述代码：
import jsonpath
resp = response.json() # 将返回值转换成字典格式
token = jsonpath.jsonpath(resp, '$..token') # token的jsonpath表达式：$..token
print(token[0])
执行结果：
d653d78ac417f65e1cd38c6f3e220341
Jsonpath表达式解析的优点：如果响应体缺少某个字段，通过Jsonpath表达式解析不到结果，就会返回False，永远不会发生异常。我们可根据返回结果进行后续处理。
import jsonpath
resp = response.json() # 将返回值转换成字典格式
# 使用错误的jsonpath表达式
token = jsonpath.jsonpath(resp, '$..token1') # token的jsonpath表达式：$..token1
if isinstance(token, List):
print(f'可以解析到token，值为：{token[0]}')
else:
print(f'解析不到token，结果为：{token}')
# 使用正确的jsonpath表达式
token = jsonpath.jsonpath(resp, '$..token') # token的jsonpath表达式：$..token
if isinstance(token, List):
print(f'可以解析到token，值为：{token[0]}')
else:
print(f'解析不到token，结果为：{token}')
执行结果：
解析不到token，结果为：False
可以解析到token，值为：d653d78ac417f65e1cd38c6f3e220341
3、如何知道自己写的jsonpath表达式是否正确呢？
jsonpath在线校验工具：http://jsonpath.com/
将response粘贴在Inputs区域，在JSONPath区域输入表达式，在Evaluation Results区域查看是否解析到期望的值。当解析不到值时，返回的是空列表（No match）
jsonpath表达式语法
九、获取请求的信息
print(f'请求url：{response.request.url}')
print(f'请求方法：{response.request.method}')
print(f'请求Header：{response.request.headers}')
print(f'请求路径：{response.request.path_url}')
执行结果：
请求url：http://shop-xo.hctestedu.com/index.php?s=api/user/login&application=app&application_client_type=weixin
请求方法：POST
请求Header：{'User-Agent': 'python-requests/2.28.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': '*/*', 'Connection': 'keep-alive', 'Content-Length': '69', 'Content-Type': 'application/json'}
请求路径：/index.php?s=api/user/login&application=app&application_client_type=weixin
十、json=data 和 data=data 参数区别
接口电商项目后台代码（PHP）中，json=data以及data=data这2种参数类型都可以接收。在实际项目应用中，常见的报文格式是application/json。因此最常使用的是json=data
1、json=data
请求头默认为:Content-Type=application/json
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, json=data, params=param_data)
# 查看请求中的请求头信息，Content-Type=application/json
print(res.request.headers)
print(res.text)
执行结果：
{'User-Agent': 'python-requests/2.28.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': '*/*', 'Connection': 'keep-alive', 'Content-Length': '69', 'Content-Type': 'application/json'}
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xxxxx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xxxxx","is_mandatory_bind_mobile":0,"token":"d653d78ac417f65e1cd38c6f3e220341"}}
2、data=data
请求头默认为：application/x-www-form-urlencoded
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, data=data, params=param_data)
# 查看请求中的请求头信息，Content-Type=application/x-www-form-urlencoded
print(res.request.headers)
print(res.text)
执行结果：
{'User-Agent': 'python-requests/2.28.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': '*/*', 'Connection': 'keep-alive', 'Content-Length': '50', 'Content-Type': 'application/x-www-form-urlencoded'}
{"msg":"登录成功","code":0,"data":{"id":"22299","username":"xxxxx","nickname":"","mobile":"","email":"","avatar":"http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg","alipay_openid":"","weixin_openid":"","weixin_unionid":"","weixin_web_openid":"","baidu_openid":"","toutiao_openid":"","qq_openid":"","qq_unionid":"","integral":"0","locking_integral":"0","referrer":"0","add_time":"1678005098","add_time_text":"2023-03-05 16:31:38","mobile_security":"","email_security":"","user_name_view":"xxxxx","is_mandatory_bind_mobile":0,"token":"d653d78ac417f65e1cd38c6f3e220341"}}
3、设置请求头
如果是java项目，spring会将请求实体的内容自动转换为Bean，但前提是请求的Content-Type必须设置为application/json
在请求头中定义发送报文的格式
1、Content-Type: application/json
headers = {
'Content-Type': 'application/json'
# 'Content-Type': 'application/x-www-form-urlencoded'
}
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, params=param_data, json=data, headers=headers)
print(res.request.headers)
执行结果：
{'User-Agent': 'python-requests/2.28.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': '*/*', 'Connection': 'keep-alive', 'Content-Type': 'application/json', 'Content-Length': '50'}
2、Content-Type：application/x-www-form-urlencoded
headers = {
# 'Content-Type': 'application/json'
'Content-Type': 'application/x-www-form-urlencoded'
}
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, params=param_data, data=data, headers=headers)
print(res.request.headers)
执行结果：
{'User-Agent': 'python-requests/2.28.1', 'Accept-Encoding': 'gzip, deflate', 'Accept': '*/*', 'Connection': 'keep-alive', 'Content-Type': 'application/x-www-form-urlencoded', 'Content-Length': '69'}
十一、Json和字典数据转换
1、json.dumps()，将字典转换成Json
使用json.dumps()可以将字典转换成Json
test = {
"msg": "登录成功",
"code": 0,
"data": {
"id": "22299",
"username": "Summer",
"nickname": "",
"mobile": "",
"email": "",
"avatar": "http:\/\/shop-xo.hctestedu.com\/static\/index\/default\/images\/default-user-avatar.jpg",
"alipay_openid": "",
"weixin_openid": "",
"weixin_unionid": "",
"weixin_web_openid": "",
"baidu_openid": "",
"toutiao_openid": "",
"qq_openid": "",
"qq_unionid": "",
"integral": "0",
"locking_integral": "0",
"referrer": "0",
"add_time": "1678005098",
"add_time_text": "2023-03-05 16:31:38",
"mobile_security": "",
"email_security": "",
"user_name_view": "chengcheng",
"is_mandatory_bind_mobile": 0,
"token": "d653d78ac417f65e1cd38c6f3e220341"
}
}
print(type(test))
print(json.dumps(test))
print(type(json.dumps(test)))
执行结果：
{"msg": "\u767b\u5f55\u6210\u529f", "code": 0, "data": {"id": "22299", "username": "Summer", "nickname": "", "mobile": "", "email": "", "avatar": "http:\\/\\/shop-xo.hctestedu.com\\/static\\/index\\/default\\/images\\/default-user-avatar.jpg", "alipay_openid": "", "weixin_openid": "", "weixin_unionid": "", "weixin_web_openid": "", "baidu_openid": "", "toutiao_openid": "", "qq_openid": "", "qq_unionid": "", "integral": "0", "locking_integral": "0", "referrer": "0", "add_time": "1678005098", "add_time_text": "2023-03-05 16:31:38", "mobile_security": "", "email_security": "", "user_name_view": "chengcheng", "is_mandatory_bind_mobile": 0, "token": "d653d78ac417f65e1cd38c6f3e220341"}}
2、json.loads()，将Json转换成字典
使用json.loads()可以将Json转换成字典
print(json.loads(json.dumps(test)))
print(type(json.loads(json.dumps(test))))
执行结果：
{'msg': '登录成功', 'code': 0, 'data': {'id': '22299', 'username': 'Summer', 'nickname': '', 'mobile': '', 'email': '', 'avatar': 'http:\\/\\/shop-xo.hctestedu.com\\/static\\/index\\/default\\/images\\/default-user-avatar.jpg', 'alipay_openid': '', 'weixin_openid': '', 'weixin_unionid': '', 'weixin_web_openid': '', 'baidu_openid': '', 'toutiao_openid': '', 'qq_openid': '', 'qq_unionid': '', 'integral': '0', 'locking_integral': '0', 'referrer': '0', 'add_time': '1678005098', 'add_time_text': '2023-03-05 16:31:38', 'mobile_security': '', 'email_security': '', 'user_name_view': 'chengcheng', 'is_mandatory_bind_mobile': 0, 'token': 'd653d78ac417f65e1cd38c6f3e220341'}}
3、json格式报文发送
方法一：参数是data，值：将字典data转换成json
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
headers = {
'Content-Type': 'application/json'
}
res = requests.post(url=url, data=json.dumps(data), headers=headers)
print(res.text)
方法二：参数是json，值：字典data
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, json=data)
print(res.text)
print(res.json())
print(type(res.json()))
assert "登录成功" == res.json()['msg']
十二、获取接口响应时间
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
res = requests.post(url=url, json=data)
print(res.text)
# 获取接口响应时间，单位秒
print(r.elapsed.total_seconds())
执行结果：
{"msg":"登录成功","code":0,"data":{"body_html":""}}
0.078264
十三、接口调用失败处理
同一个用例中有多个接口调用，一个接口调用失败如何防止程序终止？
用于判断接口请求的状态码是否为200，如果是，则返回none，如果不是则返回异常。
调用接口时结合try…except进行使用。
# 模拟接口404，使用不存在的request url: login1
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login1'
res = requests.post(url=url, json=data)
try:
assert 200 == res.status_code
except:
# 异常处理1：直接跳过，可继续执行后面代码
# pass
# 异常处理2：打印详细异常信息
print(res.status_code)
res.raise_for_status()
else:
print(res.text)
执行结果：
404
Traceback (most recent call last):
File "E:\Coding\python-workspace\Interface_test\first_requests.py", line 220, in
assert 200 == res.status_code
AssertionError
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "E:\Coding\python-workspace\Interface_test\first_requests.py", line 226, in
res.raise_for_status()
File "D:\Developer\Python\Python310\lib\site-packages\requests\models.py", line 1021, in raise_for_status
raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 404 Client Error: Not Found for url: http://shop-xo.hctestedu.com/index.php?s=api/user/login1
十四、接口超时
url = 'http://shop-xo.hctestedu.com/index.php?s=api/user/login'
try:
res = requests.post(url=url, json=data, timeout=0.01) # timeout，单位秒
except (TimeoutError, ReadTimeout, ConnectTimeout):
# ConnectTimeout：指的是建立连接所用的时间，适用于网络状况正常的情况下，两端连接所用的时间。
# ReadTimeout：指的是建立连接后从服务器读取到可用资源所用的时间。
print("发生错误，请稍后重试")
else:
# 获取接口响应时间，单位秒
print(res.elapsed.total_seconds())
print(res.text)
执行结果：
发生错误，请稍后重试
当把timeout改成0.1，执行结果：
0.07419
{"msg":"登录成功","code":0,"data":{"body_html":""}}