[learning] interface test case writing and testing concerns

One 、 Why do interface tests

In the daily development process , Someone does front-end development , Someone's in charge of back-end development . Interface is to connect the front and back , Because the speed of front-end development and back-end development may not be the same , For example, the back end is developed , But the front end is not developed . So we don't need to test ？ Most of us do function tests , Many are functional tests of the interface . If you understand interface testing , Then you can test the interface .

Two 、 What is an interface 、 What is interface testing

Interface ： It is mainly the interaction and interaction between sub modules or subsystems .

The interface here is generalized , The protocol between client and background service ; The interface of communication between plug-ins ; Interface between modules ; As small as a method provided by a class ; Can be understood as interface .

The interface test ： It refers to the testing of interfaces between modules or systems .

3、 ... and 、 Interface test process

Demand discussion , Requirements review , Scene design , Write Columns , Prepare the data , Perform the test

Four 、 Interface test case design

1 Use case design for interface testing , Mainly from the input and interface processing two aspects of consideration ：

1） For input , It can be designed according to the parameter type ;

2） For interface processing , Use case design can be done according to logic ;

3） For output , Analysis and design can be made according to the results .

2 Design for input

For interfaces , Input is input parameter . Common parameter types are :

（1） Numerical type (int,long,float,double etc. ）

（2） String type

（3） An array or list

（4） Structure

5、 ... and . How to test the interface

Through the tool simulation, the client sends the request to the server and receives the data returned by the server to perform the function of the interface , Logic business , abnormal , Security testing

A functional test ： Test whether the function of this interface is realized , And test whether the interface is developed according to the interface document （ For example, the interface document specifies some keywords , When I was big, I changed the keywords to other keywords , Because throughout the project cycle , It's not just one development, it's multiple , Therefore, it may be due to the different keywords in the development process that some development functions are abnormal , There are also exceptions to automated scripts ）

　　 Logic business , It mainly refers to some logical business dependencies （ For example, when Alipay submits an order, you must ensure that you are logged in , If you don't log in and submit successfully , This is the anomaly , You can modify the requested cookie To test ）

　　 Abnormal test ： Parameter exception ： Key parameters （ Test with other keyword substitutions ）、 The parameter is empty. 、 How many parameters （ Add the number by adding parameters ）, Parameter error . Data exception ： Keyword data （ Fill in the data with other data language data instead of ）、 Data length 、 Data is empty 、 Data error .

　　 Because the front and back calls of our project are mainly based on http Interface to protocol , So when testing the interface, it is mainly through tools or code simulation http Sending and receiving of requests . There are many tools like ：apipost、jmeter、java+httpclient、robotframework+httplibrary etc. .
　　– It can also be used. Interface automation to achieve , It's code implementation , The framework and UI Automation is almost , Send request to judge by assertion .

6、 ... and 、 Tools for interface testing

Common tools for interface testing ,fiddler Grab request ,apipost Simulate the client by fiddler The request is modified and sent to the server and receives the data and exception returned by the server to verify the interface . Tools are not fixed , You need to choose according to the project .

7、 ... and 、 Typical problems found in interface testing

Interface testing often encounters bug And questions , as follows ：

（1） Improper handling of incoming parameters , Cause procedure crash;

（2） Type overflow , Result in inconsistent data reading and writing ;

（3） Because the object permission is not checked , Access to sensitive information from other users ;

（4） Improper state handling , It leads to the confusion of logic ;

（5） The logic check is not perfect , We can take advantage of loopholes to gain illegitimate benefits .

 

Tools download link ：

ApiPost - Directly generated documents API debugging 、 Management tools ​