Testing RESTful Web Services

W15
Testing Web Services
10/18/2017 3:00:00 PM
Testing RESTful Web Services
Presented by:
Hilary Weaver-Robb
Quicken Loans
Brought to you by:
350 Corporate Way, Suite 400, Orange Park, FL 32073
888-‐268-‐8770 ·∙ 904-‐278-‐0524 - info@techwell.com - https://www.techwell.com/

Hilary Weaver-Robb
Quicken Loans
Hilary Weaver-Robb is a software quality architect at Detroit-based Quicken
Loans. She is a mentor to her fellow QA team members, makes friends with
developers, and helps teams level-up their quality processes, tools, and
techniques. Hilary has always been passionate about improving the relationships
between developers and testers, and evangelizes software testing as a
rewarding, viable career. She runs the Motor City Software Testers user group,
working to build a community of quality advocates. Hilary tweets (a lot) as
@g33klady, and you can find tweet-by-tweet recaps of conferences she's
attended, as well as her thoughts and experiences in the testing world, at
g33klady.com.

9/6/2017
1
TESTING RESTFUL WEB SERVICES Hilary Weaver-Robb
@G33KLADY | G33KLADY.COM | GITHUB.COM/G33KLADY
WHO DIS
Hilary Weaver-Robb
SQA Architect, Quicken Loans - Detroit
@g33klady
G33klady.com
Github.com/g33kladyGithub.com/g33klady

9/6/2017
2
OBJECTIVE
What a Web service is
What makes a Web service RESTful
Why we should test Web services
How to test RESTful Web services
WHAT IS A WEB SERVICE?
A Web service is a method of communication between two electronic devices over
a network.
It is a software function provided at a network address over the Web with the
service always on as in the concept of utility computing.
The W3C defines a Web service generally as: a software system designed to
support interoperable machine-to-machine interaction over a network.
- Wikipedia

9/6/2017
3
WHAT IS A WEB SERVICE?
A website provides information consumable by humans
A web service provides information consumable by software
- A genius on StackOverflow
All Web services are APIs, but not all APIs are Web services
WHAT MAKES A WEB SERVICE RESTFUL?

9/6/2017
4
WHAT IS REST?
A way for systems to talk to one another (not always Web services)
REST stands for REpresentational State Transfer
Constraints:
 Uniform Interface
 Stateless
 Cacheable
 Client-Server
 Layered System
Client-Server architecture using HTTP protocol
 Client sends Request to Server
 Server sends Response back

9/6/2017
5
URL tells you what you’re working with and doing
Messages can be lightweight (even just the URL!)
CRUD operations using HTTP methods
 Create/Update data (POST, PUT)
 Read data (GET)
 Delete data (DELETE)
WAY easier to test than non-RESTful services
COMPARISON

9/6/2017
6
HTTP RESPONSE CODES
200s – OK!
400s – What you’re asking for, we can’t do
500s – Should only be uncontrollable circumstances
WHY SHOULD WE TEST WEB SERVICES?

9/6/2017
7
WHY TEST WEB SERVICES?
Usually complete before UI is even started
Validate the ductwork
UI can pull in multiple Web services
Because it’s code!
Integration Tests
UI Tests
Unit Tests

9/6/2017
8
HOW CAN I TEST RESTFUL WEB SERVICES?
HOW CAN I FIGURE OUT WHAT TO TEST?
Documentation
Swagger
WADL/WSDL
RAML (RESTful API Modeling Language)

9/6/2017
9
HOW CAN I FIGURE OUT WHAT TO TEST?
Check out the code
 Controllers
 Models
 Tests
Run web debugger and follow the calls
HOW CAN WE TEST WEB SERVICES?
Manual Testing Tools
 Postman
 Fiddler
 Advanced REST Client
 ReadyAPI (SoapUI)
 Swagger
Automation Tools
 Postman
 ReadyAPI
 Most unit testing frameworks
Swagger

9/6/2017
10
WHAT TYPES OF TESTS CAN WE PERFORM?
Smoke tests
CRUD tests
Boundary
Required Fields
Field Type
Error ConditionsError Conditions
Security
Performance
LET’S DO SOME TESTING!
Gitter API
 GitHub chat
 https://gitter.im
 Interact with rooms, users, and messages

9/6/2017
11
MESSAGES RESOURCE SPECS
List messages
 GET https://api.gitter.im/v1/rooms/:roomId/chatMessages
Get a message
 GET https://api.gitter.im/v1/rooms/:roomId/chatMessages/:messageId
Send a message
 POST https://api.gitter.im/v1/rooms/:roomId/chatMessages
Update a messagep g
 PUT https://api.gitter.im/v1/rooms/:roomId/chatMessages/:messageId
? # of characters
Can be created, updated, read via API
Can be “deleted” but not via API

9/6/2017
12
CRUD
TESTING CRUD OPERATIONS
Create, Read, Update, Delete
Test separately to validate each method works
Test the lifecycle of an object
 Catch issues with caching or concurrency
Create -> Read -> Update -> Read -> Delete -> Read

9/6/2017
13

9/6/2017
14

9/6/2017
15

9/6/2017
16
BOUNDARIES

9/6/2017
17
TESTING BOUNDARIES
Above and below numerical limits
Value must be <= 19.9 and Value must be > 0
TESTING BOUNDARIES
How long can a message be?
 2402 worked
 6666 didn’t (400 Bad Request)
 4001 worked, 4151 didn’t
 4096 worked, 4097 didn’t
 4096 ASCII characters – UI blocks from > 4096
 4096 Unicode snowmen ☃
 4096 Japanese characters
We’ll visit this again with automation!

9/6/2017
18
REQUIRED FIELDS
TESTING REQUIRED FIELDS
If required data is omitted, it yields an accurate response
If I fail to submit required information
 Will I be able to understand how to fix it?
 Is it handled gracefully?
 Is the request processed as if it wasn’t required?

9/6/2017
19

9/6/2017
20

9/6/2017
21
FIELD TYPES
TESTING FIELD TYPES
If the client sends a different data type than what is expected
 Expect INTEGER, send
 STRING
 DECIMAL
☃
Send a Message only has StringsSend a Message only has Strings
 Accepts Unicode and UTF-8
 BORING

9/6/2017
22
TESTING FIELD TYPES

9/6/2017
23
TESTING FIELD TYPES

9/6/2017
24
FAILURE
TESTING FOR FAILURE
Testing for uncontrollable circumstances
 500 Internal Server Error
 Timeouts
 404s
 Server Down
 Database not responding
How does the UI react when Web service has these issues?
Test for 3rd Party APIs having these issues
Use Service Virtualization

9/6/2017
25
SECURITY

9/6/2017
26
TESTING SECURITY
Authentication vs. Authorization
Authentication
(who they are)
Does the
Authorization
(what they can do)
Does the
token allow
request have
a valid token?
token allow
access to this
resource?
TESTING SECURITY
Encryption
 Use Fiddler or Wireshark to see what the requests look like “over the wire”
SQL Injection
Fuzzing
 Sending tons of malformed data and see where it breaks

9/6/2017
27
EXPLORATORY
EXPLORATORY TESTING
Test design and test execution at the same time
– James Bach
Not scripted
Not pre-planned
Let the application lead you
Use your past experience as heuristicsUse your past experience as heuristics

9/6/2017
28
EXPLORATORY TESTING WEB SERVICES
Apply the same principles as with a GUI interface
Think about other uses
 What else uses the API now?
 What else could use the API in the future?
EXPLORATORY TESTING WEB SERVICES
q
 No documentation

9/6/2017
29

9/6/2017
30
AUTOMATED CHECKING
AUTOMATED CHECKING OF WEB SERVICES
Automate what can be checked repeatedly
Binary decisions (true or false) can be automated
 Does response code match what I’m expecting for this request?
 Is the response time within the SLA?

9/6/2017
31
AUTOMATION PROCESS
Decide on tooling
Common Utility Methods
 Performing the Web request
 Reading response content
 Performing a query of a database
Models
 Classes for the requests and responses
 Easier to manipulate an object for testing than a string
Write integration tests!
AUTOMATION PROCESS
Create utility method(s)
Create or reference models of requests and responses
App.config to hold auth keys, URIs, etc

9/6/2017
32

9/6/2017
33
AUTOMATION PROCESS
Start writing small, simple tests
 Hit the service with a valid request, get a 200 back?
 Hit the service, validate we get a specific field back correctly?
 Hit the service, validate we get a certain number of items?

9/6/2017
34
AUTOMATION PROCESS
Make it more interesting (and complicated)
 POST to the service, validate it posted
 Subsequent GET to the service
 Read from the database
 CRUD operations, in order

9/6/2017
35
AUTOMATION PROCESS
Data-driven tests
 Same test structure, just different data and expected results
 Required fields (especially if there are a lot)
 Boundary tests
 0 characters – 200 OK
 10 characters – 200 OK
 4096 characters 200 OK 4096 characters – 200 OK
 4097 characters – 400 BAD REQUEST

9/6/2017
36
AUTOMATE ALL THE THINGS!
Combine Integration and GUI Automation!
Example for Messages resource
 POST via Web Service
 Get the message ID and timestamp from the response body
 Launch the web app with Selenium
 Assert that message ID, with that timestamp and message text, appears properly
TEST THOSE WEB SERVICES!

9/6/2017
37
TEST THOSE WEB SERVICES
No pretty UI for end users
 Bugs in Web services cause just as many headaches for users
Different skill set for testers
 A lot of the same principles
Seems complicated
 Just a different window into our applications
THAT’S IT!
Code, Postman Collection, and Resources
https://github.com/g33klady/TestingRESTServices
Questions?Questions?

Testing RESTful Web Services

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Ähnlich wie Testing RESTful Web Services

Ähnlich wie Testing RESTful Web Services (20)

Mehr von TechWell

Mehr von TechWell (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Testing RESTful Web Services