KEMBAR78
Api FUNdamentals #MHA2017 | PDF
Welcome!
• We’ll use postman for some of our examples. If you would like to follow along,
download postman now. www.getpostman.com.
• Feel free to pair with someone!
• Our Postman demo collection will be available with our presentation materials.
• Follow @apidemo_carter onTwitter!
JoEllen Carter / Lisa Crispin
Overview
• What is an API?
• History of API growth
• Current API landscape
• HowAPIs work, including some hands-on demos
• Strategies and tools for testing an API
• API Stories
What is an
Application
Programming
Interface?
!!!
Interfaces
• Touch
• Voice
• Sight
API
Your
application The world !!!
2000 2002 2004 2006 2008
Why RESTful?
• REST: Representational state transfer
• Uniform and predefined set of stateless
operations
• People can “just know things” about an API
that’s RESTful
How does an
Application Programming
Interface
Work?
RPC SOAP HTTP HTTPS CoAP …
HTTPRequest
URL
Method
Headers
Body
URL
https://api.twitter.com/1.1/statuses/update.json?status=testing
{base url} / {version} / {endpoint} ? {query parameters}
GET
• Get some data about an object or
‘resource’
POST • Create a new resource
PUT • Update a resource
DELETE • Delete a resource
Methods
Headers
• Headers are key/value combinations that specify
additional information about the request
• Some common request headers are:
• Content-type
• Authentication
• Accept
• Origin
Body
• Data to send with the
request – usually for a
POST or PUT
• Data format – xml,
json, etc. - is specified
by the content-type
header
{
"location": {
"lat": -33.8669710,
"lng": 151.1958750
},
"accuracy": 50,
"name": "Google Shoes!",
"phone_number": "(02) 9374
4000",
"address": "48 Pirrama Road,
Pyrmont, NSW 2009, Australia",
"types": ["shoe_store"],
"website":
"http://www.google.com.au/",
"language": "en-AU"
}
What about cookies?
• Restful API requests should be self-reliant
• Cookies are session-dependent, so not
independent
• Using cookies to store data means your
API is not Restful
Authentication
• Insecure - Authorization token in url
• https://api.darksky.net/forecast/{{token}}
/39.9026420,-105.0905190
• https://maps.googleapis.com/maps/api/p
lace/nearbysearch/json?key={{googlema
psKey}}
• Basic
• Username:password are concatenated
and encoded
• Sent in Authorization header
Authentication - Oauth
• Oauth1/2 - https://oauth.net/
Service Provider
Authentication - JWT
JSON WebToken https://jwt.io/ - an open standard (RFC 7519)
that defines a compact and self-contained way for securely
transmitting information between parties as a JSON object.
• Header – type of token (JWT) and hashing (signing) algorithm
• Payload – contains ‘claims’, or information about the user
• Signature = signature from header-specified algorithm using
encoded Header + encoded payload + secret
Let’s try a GET now…
• We’ll hit the dark sky api to get our current
weather
HTTPResponse
URL
Status Code
Headers
Body
OK200
Bad Request400
Forbidden403
Not Found404
Internal Server Error500
Service Unavailable503
GatewayTimeout504
Common
Status
Codes
Let’s try a POST now…
• We’ll post a tweet from #MHA2017
How do we
test
API’s?
Security
• Basic
• Authentication tokens are valid/present
• Account boundaries are not violated
• SSL is enforced/warned when not present
• Hacker-in-training
• Injection points – headers, parameters, body
• Recording tools – what is exposed/available
• White Hat hacker - OWASP
• Rest Security Cheat Sheet
• OWASP top 10 security vulnerabilities – new
section on Under-protected APIs
Functional
• Basic
• Correct status codes are generated for invalid
inputs
• Request/response bodies contain the correct
content type and schema
• Backwards-compatibility for public APIs -
previous tests continue to pass or breaking
changes are clearly documented – aka
regression testing
• Advanced
• Join API requests together to mirror application
functionality
Exploratory
• Identify the variable bits - things that can/will/might
change
• Requests –
• Method
• Mix/match endpoints
• Parameters
• Headers, especially content type
• ContentType
• Size, Depth - images, json/xml nesting
• Timing & Frequency – what happens with caching?
Heuristics
• Apply Heuristics to the variables
• Zero, One, Many
• Some, None,All
• Beginning, Middle, End
• Too Many,Too Few
• Relative Position, i.e. content
Automation
• Part of your CI/CD pipeline
• Part of development process since tests can be
run in both local and pre-production
environments
• Performance
• Combine tests with monitoring
• Tools
• Postman
• Command line runner that can be integrated
into your CI
• Developer adoption is high
• Runscope
• Powerful code snippets
Supporting an API
Tracker API, rewritten in 2012-13
• Our own client software uses public API, same as customers
• With some private endpoints
• Leading practices: RESTful, JSON in & out,
• Versioning
• Only changes are additions
• Promote new endpoints through various stages
• “edge” version
• Metadata-driven
• Reference doc generated from metadata and unit test outputs
Long-term results
• Few support requests
• Thanks to comprehensive unit tests, comprehensive doc & examples
• Comprehensive doc for devs to introduce new endpoints
• Many new endpoints added
• Mostly without pain – one backwards compatibility issue
• Postman regression tests run in CI in addition to unit tests
• Include performance checks
Questions? Stories?
Take-aways
• APIs are the engine behind the apps we
use every day
• APIs are an integral part of our agile
processes - APIs make apps more testable,
and can be tested!
• APIs add value to your product - maybe
your company/product/team needs an
API?
• You’ve learned some terms about RESTful
web services – go forth and learn more!
Links
• ProgrammableWeb
• API Security Testing
• OWASPTop 10 Project
• List of HTTP Header fields
• Varonis - Introduction to Oauth
• Oauth.net
• Understanding rest and rpc

Api FUNdamentals #MHA2017

  • 1.
    Welcome! • We’ll usepostman for some of our examples. If you would like to follow along, download postman now. www.getpostman.com. • Feel free to pair with someone! • Our Postman demo collection will be available with our presentation materials. • Follow @apidemo_carter onTwitter!
  • 2.
    JoEllen Carter /Lisa Crispin
  • 3.
    Overview • What isan API? • History of API growth • Current API landscape • HowAPIs work, including some hands-on demos • Strategies and tools for testing an API • API Stories
  • 4.
  • 5.
  • 6.
  • 8.
  • 9.
    2000 2002 20042006 2008
  • 11.
    Why RESTful? • REST:Representational state transfer • Uniform and predefined set of stateless operations • People can “just know things” about an API that’s RESTful
  • 13.
    How does an ApplicationProgramming Interface Work?
  • 14.
    RPC SOAP HTTPHTTPS CoAP …
  • 15.
  • 16.
  • 17.
    GET • Get somedata about an object or ‘resource’ POST • Create a new resource PUT • Update a resource DELETE • Delete a resource Methods
  • 18.
    Headers • Headers arekey/value combinations that specify additional information about the request • Some common request headers are: • Content-type • Authentication • Accept • Origin
  • 19.
    Body • Data tosend with the request – usually for a POST or PUT • Data format – xml, json, etc. - is specified by the content-type header { "location": { "lat": -33.8669710, "lng": 151.1958750 }, "accuracy": 50, "name": "Google Shoes!", "phone_number": "(02) 9374 4000", "address": "48 Pirrama Road, Pyrmont, NSW 2009, Australia", "types": ["shoe_store"], "website": "http://www.google.com.au/", "language": "en-AU" }
  • 20.
    What about cookies? •Restful API requests should be self-reliant • Cookies are session-dependent, so not independent • Using cookies to store data means your API is not Restful
  • 21.
    Authentication • Insecure -Authorization token in url • https://api.darksky.net/forecast/{{token}} /39.9026420,-105.0905190 • https://maps.googleapis.com/maps/api/p lace/nearbysearch/json?key={{googlema psKey}} • Basic • Username:password are concatenated and encoded • Sent in Authorization header
  • 22.
    Authentication - Oauth •Oauth1/2 - https://oauth.net/ Service Provider
  • 24.
    Authentication - JWT JSONWebToken https://jwt.io/ - an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. • Header – type of token (JWT) and hashing (signing) algorithm • Payload – contains ‘claims’, or information about the user • Signature = signature from header-specified algorithm using encoded Header + encoded payload + secret
  • 25.
    Let’s try aGET now… • We’ll hit the dark sky api to get our current weather
  • 26.
  • 27.
    OK200 Bad Request400 Forbidden403 Not Found404 InternalServer Error500 Service Unavailable503 GatewayTimeout504 Common Status Codes
  • 28.
    Let’s try aPOST now… • We’ll post a tweet from #MHA2017
  • 29.
  • 30.
    Security • Basic • Authenticationtokens are valid/present • Account boundaries are not violated • SSL is enforced/warned when not present • Hacker-in-training • Injection points – headers, parameters, body • Recording tools – what is exposed/available • White Hat hacker - OWASP • Rest Security Cheat Sheet • OWASP top 10 security vulnerabilities – new section on Under-protected APIs
  • 31.
    Functional • Basic • Correctstatus codes are generated for invalid inputs • Request/response bodies contain the correct content type and schema • Backwards-compatibility for public APIs - previous tests continue to pass or breaking changes are clearly documented – aka regression testing • Advanced • Join API requests together to mirror application functionality
  • 32.
    Exploratory • Identify thevariable bits - things that can/will/might change • Requests – • Method • Mix/match endpoints • Parameters • Headers, especially content type • ContentType • Size, Depth - images, json/xml nesting • Timing & Frequency – what happens with caching?
  • 33.
    Heuristics • Apply Heuristicsto the variables • Zero, One, Many • Some, None,All • Beginning, Middle, End • Too Many,Too Few • Relative Position, i.e. content
  • 34.
    Automation • Part ofyour CI/CD pipeline • Part of development process since tests can be run in both local and pre-production environments • Performance • Combine tests with monitoring • Tools • Postman • Command line runner that can be integrated into your CI • Developer adoption is high • Runscope • Powerful code snippets
  • 35.
    Supporting an API TrackerAPI, rewritten in 2012-13 • Our own client software uses public API, same as customers • With some private endpoints • Leading practices: RESTful, JSON in & out, • Versioning • Only changes are additions • Promote new endpoints through various stages • “edge” version • Metadata-driven • Reference doc generated from metadata and unit test outputs
  • 36.
    Long-term results • Fewsupport requests • Thanks to comprehensive unit tests, comprehensive doc & examples • Comprehensive doc for devs to introduce new endpoints • Many new endpoints added • Mostly without pain – one backwards compatibility issue • Postman regression tests run in CI in addition to unit tests • Include performance checks
  • 37.
  • 38.
    Take-aways • APIs arethe engine behind the apps we use every day • APIs are an integral part of our agile processes - APIs make apps more testable, and can be tested! • APIs add value to your product - maybe your company/product/team needs an API? • You’ve learned some terms about RESTful web services – go forth and learn more!
  • 39.
    Links • ProgrammableWeb • APISecurity Testing • OWASPTop 10 Project • List of HTTP Header fields • Varonis - Introduction to Oauth • Oauth.net • Understanding rest and rpc