Agenda

• Overview of REST API
• Introduction to API testing
• Overview of different API testing frameworks
• Introduction to LCC framework(lemoncheesecake)
• Understanding the matchers/assertions available
• Generating awesome reports
• Demo

HTTP methods:

Different API testing frameworks

• Curl: curl provides a generic, language-agnostic way to demonstrate HTTP requests and responses.
• Postman: Postman is a Google Chrome app for interacting with HTTP APIs. It offers a friendly GUI for constructing requests and reading responses.
• JMeter: JMeter (open source) is widely used for functional API testing although it was actually created for load testing.
• Karate: Karate works out of the box and allows you to construct the most complex request-response operations with no knowledge of any programming language.
• Pytest: Pytest is a testing framework which allows us to write test codes using python.
• but there is more with Python..
• Let's try out some 'lemoncheesecake' ;)

lemoncheesecake: a functional test framework for Python

Getting started

lemoncheesecake can be installed via pip

$ pip install lemoncheesecake

Writing your test suite

Creating a new test project

$lcc bootstrap test-project

Creates a new project directory “test-project” containing one file “project.py” (it contains your project settings) and “suites” and "fixtures" directories for you add your test suites and fixtures.

A suite looks like:

#suites/test_get_users.py

import lemoncheesecake.api as lcc
from lemoncheesecake.matching import *
import requests


SUITE = {
    "description": "Sample API tests for GET, POST, DELETE "
}

base_url = "https://jsonplaceholder.typicode.com"

@lcc.test("Verify that GET request for users/1 gives a 200 OK")
def test_get_users():
    lcc.set_step("checking for endpoint: https://jsonplaceholder.typicode.com/users/1")
    response = requests.get(url=base_url + "/users/1")
    check_that("response code", response.status_code, equal_to(200), quiet=False)

@lcc.test("Verify that GET request for /users/1 contains required params")
def test_get_users_params():
    response = requests.get(url=base_url + "/users/1")
    result = response.json()
    check_that("the response ", result, has_entry("name"))
    require_that("the response", result, has_entry("email", contains_string("@")))
    assert_that("the response ", result, has_entry("username", equal_to("Bret")))
               

Running the test suite:

$lcc run

Console output look like:

Matchers

data = {"title": "Title 1", "uuid": "aaa11"}
check_that("title is", data, has_entry("title", equal_to("Title 1")))
check_that("uuid is", data, has_entry("uuid", equal_to("aaa11")))
                

Sample JSON Output:

{
  "id": 1,
  "name": "Leanne Graham",
  "username": "Bret",
  "email": "Sincere@april.biz",
  "address": {
    "street": "Kulas Light",
    "suite": "Apt. 556",
    "city": "Gwenborough",
    "zipcode": "92998-3874"
  },
  "phone": "1-770-736-8031 x56442",
  "website": "hildegard.org"
  }
}
                

Let's use the matchers and write more tests..

@lcc.test("Verify that GET request for /users/1 contains required params")
def test_get_users_params():
    response = requests.get(url=base_url + "/users/1")
    result = response.json()
    check_that("the response ", result, has_entry("name"))
    require_that("the response", result, has_entry("email", contains_string("@")))
    assert_that("the response ", result, has_entry("username", equal_to("Bret")))
    check_that("the response ", result, has_entry("address", is_dict()))
    require_that("the response", result, has_entry("address", has_entry("city", equal_to("Gwenborough"))))


@lcc.test("Verify that POST request to /posts is successful")
def test_post_req():
    body = {
      "title": 'Title for Devconf.CZ 2020',
      "body": 'Test title by Anisha',
      "userId": 500
    }
    response = requests.post(base_url + "/posts", data=body)
    result= response.json()
    require_that("the POST request response", response.status_code, equal_to(201))
    lcc.log_info(str(result))
    check_that("the response", result, has_entry("title", equal_to("Title for Devconf.CZ 2020")))
                

Logging

user_name = "User 1"
lcc.log_info("User name to be added: %s " % user_name)

Generating (awesome) reports

Demo

Code available here: https://github.com/anarang/lemoncheesecake101