What’s all the buzz about REST APIs, and why should you care? REST APIs are growing quickly, with enterprise and finance the fastest growing categories. REST APIs also enable apps for mobile, wearables, and Internet of Things. If you don’t yet have a content strategy for REST APIs, you may need it soon. The job market for REST APIs is hot, and you can increase your marketability and value by understanding REST API content. Be prepared by getting a head-start on what you need to know! This presentation was given at Information Development World on October 1, 2015.

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15-Minute Intro to REST APIs
Gururaj (Guru)
@guru_bs
Information Development World
September 30, 2015

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About HTTP
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• Request-response protocol
• HTTP client and HTTP server (optional HTTP proxy) protocol
HTTP Client
(Browser)
HTTP Server (Web
Server)
Request message
Response message
<Initial line – different for request and
response>
Header1: value1
Header2: value2
Header3: value3
<optional message body>

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HTTP message format examples
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REQUEST initiated by an HTTP Client
<Method> <Request URI>
HTTP/<version>
GET </path/to/file/index.html>
HTTP/1.1
Header1: value1
Header2: value2
Header3: value3
RESPONSE sent by an HTTP Server
HTTP/1.1 <HTTP status code>
Header1: value1
Header2: value2
Header3: value3
<optional message body>
<Content Type> (text/html, image/gif
etc)
<Content Length>

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Here’s an
example…
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What and where example
• Data in a table is a resource we want to read
• Database server is called database1
• Database called sampledb
• Table called employees
http://database1/sampledb/employees
• What type of content you return is up to you – XML and JSON are
common
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REST client interfaces
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Interface REST plugin examples
Command line cURL
Download link: Use cURL download wizard (http://curl.haxx.se/download.html)
Installation instructions:
On UNIX: http://www.unixnewbie.org/how-to-install-curl/
On Windows (you need cygwin - https://www.cygwin.com/) – use my team’s cURL on Windows installation
tutorial -
http://www.oracle.com/webfolder/technetwork/tutorials/obe/cloud/objectstorage/installing_cURL/installing_c
URL.html
Desktop RESTClient (wiztools.org) – The GUI version will be used in the demo today.
Download link: http://code.fosshub.com/WizToolsorg-RESTClient/downloads
Browser REST Easy (a Firefox plugin)
Download link: https://addons.mozilla.org/EN-us/firefox/addon/rest-easy/

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HTTP methods
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Method Description
OPTIONS Returns HTTP methods and other options supported by a RESTful service
GET Retrieves a single resource, or retrieve all resources in a collection
HEAD Retrieves a single resource, or retrieve all resources in a collection (headers
only)
POST Create a new resource in a collection
PUT Update a resource (full update)
PATCH Update a resource (delta update) – RFC 5789
DELETE Delete a resource

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HTTP statuses
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Status Code Description
1xx Informational - request received, continuing process
2xx Success - action requested by the client was received,
understood, accepted and processed successfully
3xx Client must take additional action to complete the
request. Many of these status codes are used in URL
redirection
4xx Client errors
5xx Server errors

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Intro to the demo
We will use Oracle Storage Cloud Service, an object storage solution from Oracle built on
top of open stack swift API
1. Sign up for Oracle Storage Cloud Service trial
– REST end point/URL
– User name and password
2. Get an authentication token (GET) – 30-minute validity – a different service with its
own end point to grant a time-bound token
3. See which HTTP methods are supported (OPTIONS)
4. Create a storage Container (PUT)
5. Set container metadata (POST): number of objects in a container
6. Delete the container (DELETE)
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Demo Screenshots
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REST endpoint

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Useful links
• XML and JSON examples: http://json.org/example
• HTTP spec: http://www.w3.org/Protocols/rfc2616/rfc2616.html
• A story of how a web developer explained REST to his wife: http://www.looah.com/source/view/2284
• HTTP status codes: http://httpstatus.es/
• Oracle Storage Cloud Service Trial: http://cloud.oracle.com/storage
• My team’s cURL on Windows installation tutorial -
http://www.oracle.com/webfolder/technetwork/tutorials/obe/cloud/objectstorage/installing_cURL/insta
lling_cURL.html
• Oracle Storage Cloud Service documentation:
http://docs.oracle.com/cloud/latest/storagecs_common/CSSTO/GUID-5778ADBB-A0E8-4451-B886-
362A3B7237DB.htm#CSSTO3177
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Demo screenshots
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Authentication Error
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GET – Authentication Token
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OPTIONS – View the methods allowed
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PUT – Create a container
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GET– View the newly created container
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POST– set container metadata (quota and number of objects)
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POST– status
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DELETE– delete the container
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GET– view the list of containers to verify the deletion of Guru_Cont4
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