Hvad er BDD-testning? Rammeeksempel
Hvad er BDD-test (Behavior Driven Development)?
BDD (Adfรฆrdsdrevet udvikling) Test er en teknik til agil softwareudvikling og er i forlรฆngelse af TDD, dvs. Test Driven Development. I BDD er testcases skrevet i et naturligt sprog, som selv ikke-programmรธrer kan lรฆse.
Hvordan fungerer BDD-test?
Overvej, at du er blevet tildelt til at oprette pengeoverfรธrselsmodul i en Net Banking-applikation.
Der er flere mรฅder at teste det pรฅ
- Pengeoverfรธrsel bรธr finde sted, hvis der er nok saldo pรฅ kildekontoen
- Pengeoverfรธrsel bรธr finde sted, hvis destinations-a/c-oplysningerne er korrekte
- Pengeoverfรธrsel bรธr finde sted, hvis transaktionsadgangskode / rsa-kode / sikkerhedsgodkendelse for transaktionen indtastet af brugeren er korrekt
- Pengeoverfรธrsel bรธr finde sted, selvom det er en helligdag
- Pengeoverfรธrsel bรธr finde sted pรฅ en fremtidig dato som fastsat af kontohaveren
Testscenarie blive mere kompliceret og kompleks, da vi overvejer yderligere funktioner som overfรธrselsbelรธb X i et interval Y dage/mรฅneder , stop tidsplanoverfรธrsel, nรฅr det samlede belรธb nรฅr Z , og sรฅ videre
Den generelle tendens hos udviklere er at udvikle funktioner og skrive testkode senere. Som det fremgรฅr af ovenstรฅende tilfรฆlde, Test sag udvikling for denne sag er kompleks, og udvikleren vil udsรฆtte Test indtil frigivelse, hvorefter han vil lave hurtige, men ineffektive tests.
For at overvinde dette problem (Behavior Driven Development) blev BDD udtรฆnkt. Det gรธr hele testprocessen let for en udvikler
I BDD skal det, du skriver, gรฅ ind i Givet-Hvornรฅr-Sรฅ trin. Lad os overveje det samme eksempel ovenfor i BDD
Given that a fund transfer module in net banking application has been developed And I am accessing it with proper authentication
WhenI shall transfer with enough balance in my source account Or I shall transfer on a Bank Holiday Or I shall transfer on a future date And destination a/c details are correct And transaction password/rsa code / security authentication for the transaction is correct And press or click send button
Then amount must be transferred And the event will be logged in log file
Er det ikke nemt at skrive og lรฆse og forstรฅ? Det dรฆkker alle mulige testcases for pengeoverfรธrselsmodulet og kan nemt รฆndres, sรฅ det kan rumme flere. Det er ogsรฅ mere som at skrive dokumentation til fondsoverfรธrselsmodulet.
Hvad er REST API-testning?
Da REST er blevet en ganske populรฆr stil til at bygge API'er i dag, er det blevet lige sรฅ vigtigt at automatisere REST API-testcases sammen med UI-testcases. Sรฅ dybest set HVILER disse API-test involverer test af CRUD (Create-Read-Update-Delete) handlinger med henholdsvis metoderne POST, GET, PUT og DELETE.
Hvad er Behave?
Behave er en af โโde populรฆre Python BDD-testrammer.
Lad os se, hvordan Behave fungerer:
Funktionsfiler er skrevet af din forretningsanalytiker / sponsor / hvem som helst med dine adfรฆrdsscenarier i det. Det har et naturligt sprogformat, der beskriver en funktion eller en del af en funktion med reprรฆsentative eksempler pรฅ forventede resultater
Disse scenarietrin er kortlagt med trinimplementeringer skrevet ind Python.
Og valgfrit er der nogle miljรธkontroller (kode til at kรธre fรธr og efter trin, scenarier, funktioner eller hele skydekampen).
Lad os komme i gang med opsรฆtningen af โโvores automatiseringstestramme med Behave:
Opsรฆtning af BDD Testing Framework Behave on Windows
Installation:
- Hent og installer Python 3 fra https://www.python.org/
- Udfรธr fรธlgende kommando pรฅ kommandoprompten for at installere opfรธrer sig
- pip installation opfรธrer sig
- IDE: Jeg har brugt PyCharm EF-udgave https://www.jetbrains.com/pycharm/download
Projektopsรฆtning:
- Opret et nyt projekt
- Opret fรธlgende mappestruktur:
Funktionsfiler:
Sรฅ lad os bygge vores feature-fil Sample_REST_API_Testing.feature har funktion som Udfรธrelse af CRUD-operationer pรฅ 'posts'-tjeneste.
I vores eksempel har jeg brugt http://jsonplaceholder.typicode.com/ poster eksempel REST Service.
Eksempel POST-scenarie
Scenario: POST post example ->Here we are considering creating new post item using 'posts' service Given: I set post posts API endpoint ->This is prerequisite for the test which is setting URL of posts service When: I set HEADER param request content type as "application/json." And set request body And send POST HTTP request ->This is actual test step of sending a post request Then: Then I receive valid HTPP response code 201 And Response body "POST" is non-empty-> This is verification of response body
Pรฅ samme mรฅde kan du skrive de resterende scenarier som fรธlger:
Sample_REST_API_Testing.feature
Feature: Test CRUD methods in Sample REST API testing framework
Background:
Given I set sample REST API url
Scenario: POST post example
Given I Set POST posts api endpoint
When I Set HEADER param request content type as "application/json."
And Set request Body
And Send a POST HTTP request
Then I receive valid HTTP response code 201
And Response BODY "POST" is non-empty.
Scenario: GET posts example
Given I Set GET posts api endpoint "1"
When I Set HEADER param request content type as "application/json."
And Send GET HTTP request
Then I receive valid HTTP response code 200 for "GET."
And Response BODY "GET" is non-empty
Scenario: UPDATE posts example
Given I Set PUT posts api endpoint for "1"
When I Set Update request Body
And Send PUT HTTP request
Then I receive valid HTTP response code 200 for "PUT."
And Response BODY "PUT" is non-empty
Scenario: DELETE posts example
Given I Set DELETE posts api endpoint for "1"
When I Send DELETE HTTP request
Then I receive valid HTTP response code 200 for "DELETE."
Trin implementering
Nu, for funktionstrin, der bruges i ovenstรฅende scenarier, kan du skrive implementeringer i Python filer i mappen "trin".
Behave framework identificerer Step-funktionen ved at dekoratรธrer matcher med feature fil-prรฆdikatet. For eksempel sรธger et givet prรฆdikat i Feature-fil Scenario efter trinfunktion, der har dekorator "givet". Tilsvarende matching sker for Hvornรฅr og derefter. Men i tilfรฆlde af 'Men', 'Og', tager Trin-funktionen dekorator samme som det foregรฅende trin. For eksempel, hvis 'And' kommer for Given, er matchende trinfunktionsdekorator @given.
For eksempel, nรฅr trin til POST kan implementeres som fรธlger:
@when (u'I Set HEADER param request content type as "{header_conent_type}"')
Mapping of When, here notice โapplication/jsonโ is been passed from feature file for "{header_conent_type}โ . This is called as parameterization
def step_impl (context, header_conent_type):
This is step implementation method signature
request_headers['Content-Type'] = header_conent_type
Step implementation code, here you will be setting content type for request header
Pรฅ samme mรฅde vil implementeringen af โโandre trin i step python-filen se sรฅdan ud:
sample_step_implementation.py
from behave import given, when, then, step
import requests
api_endpoints = {}
request_headers = {}
response_codes ={}
response_texts={}
request_bodies = {}
api_url=None
@given(u'I set sample REST API url')
def step_impl(context):
global api_url
api_url = 'http://jsonplaceholder.typicode.com'
# START POST Scenario
@given(u'I Set POST posts api endpoint')
def step_impl(context):
api_endpoints['POST_URL'] = api_url+'/posts'
print('url :'+api_endpoints['POST_URL'])
@when(u'I Set HEADER param request content type as "{header_conent_type}"')
def step_impl(context, header_conent_type):
request_headers['Content-Type'] = header_conent_type
#You may also include "And" or "But" as a step - these are renamed by behave to take the name of their preceding step, so:
@when(u'Set request Body')
def step_impl(context):
request_bodies['POST']={"title": "foo","body": "bar","userId": "1"}
#You may also include "And" or "But" as a step - these are renamed by behave to take the name of their preceding step, so:
@when(u'Send POST HTTP request')
def step_impl(context):
# sending get request and saving response as response object
response = requests.post(url=api_endpoints['POST_URL'], json=request_bodies['POST'], headers=request_headers)
#response = requests.post(url=api_endpoints['POST_URL'], headers=request_headers) #https://jsonplaceholder.typicode.com/posts
# extracting response text
response_texts['POST']=response.text
print("post response :"+response.text)
# extracting response status_code
statuscode = response.status_code
response_codes['POST'] = statuscode
@then(u'I receive valid HTTP response code 201')
def step_impl(context):
print('Post rep code ;'+str(response_codes['POST']))
assert response_codes['POST'] is 201
# END POST Scenario
# START GET Scenario
@given(u'I Set GET posts api endpoint "{id}"')
def step_impl(context,id):
api_endpoints['GET_URL'] = api_url+'/posts/'+id
print('url :'+api_endpoints['GET_URL'])
#You may also include "And" or "But" as a step - these are renamed by behave to take the name of their preceding step, so:
@when(u'Send GET HTTP request')
def step_impl(context):
# sending get request and saving response as response object
response = requests.get(url=api_endpoints['GET_URL'], headers=request_headers) #https://jsonplaceholder.typicode.com/posts
# extracting response text
response_texts['GET']=response.text
# extracting response status_code
statuscode = response.status_code
response_codes['GET'] = statuscode
@then(u'I receive valid HTTP response code 200 for "{request_name}"')
def step_impl(context,request_name):
print('Get rep code for '+request_name+':'+ str(response_codes[request_name]))
assert response_codes[request_name] is 200
@then(u'Response BODY "{request_name}" is non-empty')
def step_impl(context,request_name):
print('request_name: '+request_name)
print(response_texts)
assert response_texts[request_name] is not None
# END GET Scenario
#START PUT/UPDATE
@given(u'I Set PUT posts api endpoint for "{id}"')
def step_impl(context,id):
api_endpoints['PUT_URL'] = api_url + '/posts/'+id
print('url :' + api_endpoints['PUT_URL'])
@when(u'I Set Update request Body')
def step_impl(context):
request_bodies['PUT']={"title": "foo","body": "bar","userId": "1","id": "1"}
@when(u'Send PUT HTTP request')
def step_impl(context):
# sending get request and saving response as response object # response = requests.post(url=api_endpoints['POST_URL'], headers=request_headers) #https://jsonplaceholder.typicode.com/posts
response = requests.put(url=api_endpoints['PUT_URL'], json=request_bodies['PUT'], headers=request_headers)
# extracting response text
response_texts['PUT'] = response.text
print("update response :" + response.text)
# extracting response status_code
statuscode = response.status_code
response_codes['PUT'] = statuscode
#END PUT/UPDATE
#START DELETE
@given(u'I Set DELETE posts api endpoint for "{id}"')
def step_impl(context,id):
api_endpoints['DELETE_URL'] = api_url + '/posts/'+id
print('url :' + api_endpoints['DELETE_URL'])
@when(u'I Send DELETE HTTP request')
def step_impl(context):
# sending get request and saving response as response object
response = requests.delete(url=api_endpoints['DELETE_URL'])
# response = requests.post(url=api_endpoints['POST_URL'], headers=request_headers) #https://jsonplaceholder.typicode.com/posts
# extracting response text
response_texts['DELETE'] = response.text
print("DELETE response :" + response.text)
# extracting response status_code
statuscode = response.status_code
response_codes['DELETE'] = statuscode
#END DELETE
Afvikling af testene
Nu er vi fรฆrdige med vores testscript-udviklingsdel, sรฅ lad os kรธre vores test:
Udfรธr fรธlgende kommando pรฅ kommandoprompten for at kรธre vores funktionsfil
C: \Programmer\Python\Python37>opfรธre sig -f smuk C:\ \features\feature_files_mappe\Sample_REST_API_Testing.feature
Dette vil vise testudfรธrelsesresultater som fรธlger:
Rapportvisning pรฅ konsollen
Lad os se endnu en fed ting her.
Da brugere altid foretrรฆkker at se testresultater i et mere lรฆsbart og prรฆsentabelt format, lad os have rapporter i HTML-format ved hjรฆlp af Allure.
Rapporter
Fรธrst skal du installere Allure Behave formatter [https://docs.qameta.io/allure-report/]:
Og udfรธr nu fรธlgende kommando:
Til rapporter
>opfรธre sig -f json -o Sample_REST_API_Testing.feature
> lokkende tjene
Dette vil generere din testresultatrapport i det prรฆsentable og informative format som dette:
Testrapport i HTML-format
Testrapport, der viser individuelle scenarieresultater
Resumรฉ
- BDD er adfรฆrdsdrevet udvikling. Det er en af โโteknikkerne til agil softwareudvikling.
- REST er blevet en ganske populรฆr stil til at bygge API'er i dag, det er blevet lige sรฅ vigtigt at automatisere REST API-testcases sammen med UI-testcases.
- BDD har et naturligt sprogformat, der beskriver en funktion eller en del af en funktion med reprรฆsentative eksempler pรฅ forventede resultater
- Behave framework identificerer Step-funktionen ved at dekoratรธrer matcher med feature fil-prรฆdikatet
- Eksempler pรฅ BDD-testrammer: 1) Cucumber 2) SpecFlow 3) Quantum 4) JBehave 5) Codeundtagelse






