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By Tessa Mero
Understanding REST APIs in 5 Simple Steps
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REST != $this
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“It’s a way for two pieces of software to talk to each other”
Application Programming Interface
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STEP 1: Understanding the Purpose of APIs
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Why are APIs so Important?
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API Growth from 2000 to 2016
2000 2005 2007 2009 2011 2013 2015 20160
5000
10000
15000
20000
25000
30000
35000API's
API's
Source: 2016 data from nordicapis.com. 2005-2015 data from rubenverborgh.github.io and 2000-2004 data from blog.cutter.com
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An API is like …
An API (Application Programming Interface) is best thought of as a contract provided by one piece of computer software to another.
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APIs help developers create apps that benefit the end user.
Yelp asks for Map Data
Google Maps returns map data
via API
Users sees list of
restaurants close to
them
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STEP 2: Learn what REST is
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A REST API defines a set of functions which developers can perform requests and receive responses via HTTP protocol such as GET and POST.
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REST is best explained as a way to talk to other machines through the server with an HTTP Protocol
Using Verbs (actions) and Nouns (items)
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STEP 3: Know What Request and Responses are
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13
View a Web Page
Presentation ID
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14
View a Web Page
Presentation ID
Request GET /index.htm HTTP/1.1
ResponseHTTP 200 OK
<html>
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REST APIs use Request and Response too
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16
Get Data using an API (Spark)
Presentation ID
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17
Get Data using an API – Response!
Presentation ID
Request GET /rooms
ResponseHTTP 200 OK
{json data}
API Consumer API Provider
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List of Verbs!
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STEP 4: Documentation is Your Dictionary
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API Reference for Rooms (Verbs and Nouns)
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Request Parameters for “MESSAGES”
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STEP 5: Learn How to Use Debug/Test Tools for APIs
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Tools to Debug/Test http://tiny.cc/60tools
• Webhook Debugging (RequestBin formerly requestbin.org…)• Webhook Utilities (Torpio…)• Local Tunneling (ngrok...)• API Monitoring (Runscope...)• Response Mocking (mocky.io...) • JSON Utilities (JSONFormat...)• OAUTH Utilities (oauth.io...)• API Directories (APIS.io, ProgrammableWeb...)• API Testing (Runscope Radar...)• Load Testing (loader.io...)• GUI HTTP Clients (POSTMAN...)
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POSTMAN!!!!!
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25
method
url
requestheaders
status code
response headers
content-type
responsebody
query parameters
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26
Add JSON to the Body in POSTMAN
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Summary:
1. You Understand the Purpose2. You Know what REST is3. Request & Response – Makes sense4. Documentation – Live by it.5. Debugging&Test Tools – Prevent headaches
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OUI!!!!!!!!
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Thank You
@tessamerotessamero@gmail.com
http://www.slideshare.net/Tessa99