1、前言：某些接口需要引用上个接口返回的值，作为下个接口的入参，但笔者又不想在本地维护及创建此文件，此时引出fixture内置函数中的临时文件存储tmpdir

2、首先下面的源码是使用flask框架写的图书管理系统，使用的basic认证方式，调用查看数据接口时需登录返回token

from flask import  Flask,make_response,jsonify,abort,request
from flask_restful import  Api,Resource
from flask_httpauth import  HTTPBasicAuth

from flask import Flask
from flask_jwt import JWT, jwt_required, current_identity
from werkzeug.security import safe_str_cmp

app=Flask(__name__)
app.debug = True
app.config['SECRET_KEY'] = 'super-secret'
api = Api(app=app)
auth = HTTPBasicAuth()

@auth.get_password
def get_password(name):
   if name == 'admin':
      return 'admin'

@auth.error_handler
def authoorized():
   return make_response(jsonify({'msg':"请认证"}),401)

books=[
   {'id':1,'author':'Teacher','name':'Python接口自动化测试实战','done':True},
   {'id':2,'author':'Teacher','name':'Selenium3自动化测试实战','done':False},\
   {'id':3,'author':'Tao','name':'Jmeter接口测试','done':False}
]


class User(object):
   def __init__(self, id, username, password):
      self.id = id
      self.username = username
      self.password = password

   def __str__(self):
      return "User(id='%s')" % self.id

users = [
   User(1, 'admin', 'Admin'),
   User(2, 'admin', 'qwe123'),
]

username_table = {u.username: u for u in users}
userid_table = {u.id: u for u in users}

def authenticate(username, password):
   user = username_table.get(username, None)
   if user and safe_str_cmp(user.password.encode('utf-8'), password.encode('utf-8')):
      return user

def identity(payload):
   user_id = payload['identity']
   return userid_table.get(user_id, None)

jwt = JWT(app, authenticate, identity)

class Books(Resource):
   # decorators = [auth.login_required]
   decorators=[jwt_required()]

   def get(self):
      return jsonify({'status':0,'msg':'ok','datas':books})

   def post(self):
      if not request.json:
         return jsonify({'status':1001,'msg':'请求参数不是JSON的数据，请检查，谢谢！'})
      else:
         book = {
            'id': books[-1]['id'] + 1,
            'author': request.json.get('author'),
            'name': request.json.get('name'),
            'done': True
         }
         books.append(book)
         return jsonify({'status':1002,'msg': '添加书籍成功','datas':book}, 201)

class Book(Resource):
   # decorators = [auth.login_required]
   decorators = [jwt_required()]

   def get(self,book_id):
      book = list(filter(lambda t: t['id'] == book_id, books))
      if len(book) == 0:
         return jsonify({'status': 1003, 'msg': '很抱歉，您查询的书的信息不存在'})
      else:
         return jsonify({'status': 0, 'msg': 'ok', 'datas': book})

   def put(self,book_id):
      book = list(filter(lambda t: t['id'] == book_id, books))
      if len(book) == 0:
         return jsonify({'status': 1003, 'msg': '很抱歉，您查询的书的信息不存在'})
      elif not request.json:
         return jsonify({'status': 1001, 'msg': '请求参数不是JSON的数据，请检查，谢谢！'})
      elif 'author' not in request.json:
         return jsonify({'status': 1004, 'msg': '请求参数author不能为空'})
      elif 'name' not in request.json:
         return jsonify({'status': 1005, 'msg': '请求参数name不能为空'})
      elif 'done' not in request.json:
         return jsonify({'status': 1006, 'msg': '请求参数done不能为空'})
      elif type(request.json['done'])!=bool:
         return jsonify({'status': 1007, 'msg': '请求参数done为bool类型'})
      else:
         book[0]['author'] = request.json.get('author', book[0]['author'])
         book[0]['name'] = request.json.get('name', book[0]['name'])
         book[0]['done'] = request.json.get('done', book[0]['done'])
         return jsonify({'status': 1008, 'msg': '更新书籍成功', 'datas': book})

   def delete(self,book_id):
      book = list(filter(lambda t: t['id'] == book_id, books))
      if len(book) == 0:
         return jsonify({'status': 1003, 'msg': '很抱歉，您查询的书的信息不存在'})
      else:
         books.remove(book[0])
         return jsonify({'status': 1009, 'msg': '删除书籍成功'})

api.add_resource(Books,'/v1/api/books')
api.add_resource(Book,'/v1/api/book/<int:book_id>')

if __name__ == '__main__':
   app.run(debug=True,port=5550)

3、其次：把上述的登录接口分离到conftest.py 模块中，实现fixture的共享机制

import pytest
import requests

# 获取flask_api.py模块的access_token 认证登录
@pytest.fixture()
def getToken():
    login_url = "http://127.0.0.1:5550/auth"
    data = {"username": "admin","password": "Admin"}
    response = requests.post(url=login_url,json=data)
    #　返回token值
    return response.json()['access_token']

4、最后：下面举个Api接口书籍管理系统的为例（test_fixture_books_temdir.py 模块）：

import requests
import pytest

# 每一条测试用例必须有清理工作，就是原来数据是怎么的，用例执行完后还是怎么样的
# 此设置是添加书籍信息返回的ID，然后传ID更新数书籍信息，再删除此更新后的书籍信息

def addBooks(getToken):
    # 新增书籍信息
    data = {
            "author": "Teacher",
            "name": "安全&渗透测试",
            "done": False
    }
    r = requests.post(
        url='http://127.0.0.1:5550/v1/api/books',
        json=data,
        headers={'Authorization':'JWT {}'.format(getToken)}
    )
    print('添加书籍:\n',r.json())
    return r.json()[0]['datas']['id']

def queryBooks(getToken,BookID):
    #　查询书籍信息
    r = requests.get(
        url='http://127.0.0.1:5550/v1/api/book/{0}'.format(BookID),
        headers={'Authorization':'JWT {}'.format(getToken)}
    )
    print('查询书籍:\n',r.json())
    return r

def setBooks(getToken,BookID):
    # 更新书籍信息
    data = {
        "author":"TAO",
        "name":"Fiddler工具",
        "done":False
    }
    r = requests.put(
        url='http://127.0.0.1:5550/v1/api/book/{0}'.format(BookID),
        json=data,
        headers={'Authorization':'JWT {}'.format(getToken)}
    )
    print('更新书籍:\n',r.json())
    return r

def deleteBooks(getToken,BookID):
    # 删除新增书籍信息
    r = requests.delete(
        url='http://127.0.0.1:5550/v1/api/book/{0}'.format(BookID),
        headers={'Authorization':'JWT {}'.format(getToken)}
    )
    print('删除书籍:\n',r.json())

def test_query_books(getToken,tmpdir):
    fp = tmpdir.join('book.md')
    fp.write(addBooks(getToken))
    queryBooks(getToken,BookID=fp.read())
    setBooks(getToken,BookID=fp.read())
    # 验证：查询更新后书籍信息
    assert 'Fiddler' in setBooks(getToken,BookID=fp.read()).json()['datas'][0]['name']
    assert queryBooks(getToken,fp.read()).status_code == 200
    deleteBooks(getToken,BookID=fp.read())

if __name__ == '__main__':
    pytest.main()

5、下面是接口运行结果：
（接口自动化需做到，创建返回Ａ，查询返回A，更新返回Ａ，删除依然是Ａ）