KaTe RESTful adapter for SAP Process Integration: Introduction

RESTful Adapter for SAP Process IntegrationIntroduction & Overview

RESTful Adapter - Basics

What can the RESTful adapter do for you?


What can the RESTful adapter do for you?

Enable you to use SAP Process Integration to:

Publish „Pragmatic“* REST Services in XML & JSON

Invoke any„possible“ REST API or HTTP Resource

*) for a reference visit the excellent APIGee blog series on the topic


It‘s more then an just another adapter!


It‘s more then an just another adapter!

Convention over Configuration driven approach! (using metadata means less configuration)

API Console & WADL support to test & communicate with stakeholders

It‘s Developer & Operations „friendly“


The 3 main building blocks of the adapter:

The adapter runtime PI sender/receiver channels

Design Conventions Model HTTP communication by convention Metadata enables API Console

Web UI (on top of adapter) Test HTTP Calls Display API Console & WADL*

*) available upwards PI >= 7.30

Web UI

Adapter

Design Conventions(WSDL/Msgs/JSON)

Enables

Describes


What do we mean by Design Conventions?


What do we mean by Design Conventions?

ESR Conventions to model http calls as PI messages

ESR Conventions to group resources as service interfaces

Conventions to use XML internal and „speak“ JSON externally


What is the benefit of this Design Conventions?

ESR metadata drives the API Console / WADL Explain your REST API in a simple Web UI!

PI tools (mappings) can access any attribute of a http call No dynamic configurations or adaper modules needed!

Test drive any http call from the adapter Web UI Testdrive http calls before building a complete scenario

Convention over Configuration aproach!


.. JSON is enabled by Conventions too!


.. JSON is enabled by Conventions too!

Any published RESTful service is usable with XML & JSON

The adapter uses http content negotiation features to detect the expected content (Accept & Content-type headers)

No intensive configuration for JSON needed (modules etc...) Only choose: „XML compliant“ or „JSON compliant“ how XML turns into JSON

and back...

RESTful Adapter – Design Coventions

Action speaks louder then words

Let‘s see how it works by an example that comes with the adapter!


Action speaks louder then words

The adapter comes with a full CRUD example of a Partner resource stored in a database (along with more examples)

We will take a look at the example how a http POST call is modeled and published by the conventions!


Our example:

http POST call request with partner data that will return 201 Created status a location link to the new

partner resource

HTTP Client

POST http://myhost:50000/../PartnerAdapter

Location: http://myhost:50000/../Partner/1


Our example request as http call:

POST /ROAWeb/Resources/Partner?sample=123 HTTP/1.1

Host: myPIHost:50000Accept: application/xmlContent-Type: application/xml; charset=utf-8Authorization: Basic aHR0cHdhdGNoOmY= SampleHeader: testValue

<?xml version="1.0" encoding="UTF-8"?><Partner> <firstName>Anton</firstName> <lastName>Schmitt</lastName> <birthday>1977-01-12</birthday> <email>[email protected]</email></Partner>

POST data (body)

Http headers(we‘re interested in sample header)

URI Path, Method, Query Parameters


Our example request as PI request message

<urn:POST_Request xmlns:urn="urn:my:resource"> <identification> <resource name="Partner"/> <query><sample>123</sample> </query> </identification> <headers> <SampleHeader>testValue</SampleHeader> </headers> <body> <Partner> <firstName>Anton</firstName> <lastName>Schmitt</lastName> <birthday>1977-01-12</birthday> <email>[email protected]</email> </Partner> </body></urn:POST>

POST data (body)

Http headers(we‘re interested in sample header)

Parsed URI Path, Method, Query Parameters


And how would the response look like?


Our example response as PI response message:

<urn:POST_Response xmlns:urn="urn:my:resource"> <httpStatusCode>201</httpStatusCode> <headers> <location> http://myHost:50000/ROAWeb/Resources/Partner/1 </location> </headers></urn:POST>

Http headers(e.g.: here Location!)

HTTP Status: 201 Created

*) You might wonder about the origin of the Location header, this will be a few slides on ;)


Our example response as http call:

HTTP/1.1 201 Created

….Content-Type: application/xml; charset=utf-8Location: http://myhost:50000/ROAWeb/Resources/Partner/1

Http headers(e.g.: Location!)

HTTP Status: 201 Created


Now wasn‘t that simple?


Now wasn‘t that simple?

By that convention you set/access in a mapping: any path or resource id information (pre parsed) any query parameter any header parameter any http status code (or reason) any body (payload) – raw or as XML*


You might now just go and try the call with the API Console

As any call modeled by with this convention is exporable through the API Console

Just go here* on your PI Install:http://<yourPIHost>:50000/ROAWeb/Administration

*(/ROAWeb is the base path of the adaper)


The API Console enables you to:

Invoke RESTful Services (with XML & JSON)

Displays query/header parameters or the schema

Generates sample calls for PUT/POST requests


The API Console (for our POST Request)

Display Schema

Display result

Generate Sample Request

Send Payload

XML / JSON


Wait....but how did we create a current location header?


Wait....but how did we create a current location header?

The adapter comes with a mapping lib to construct relative & absolute links in the context of a call easily*

The functions take your resource ID and returns the current URI path + ID similar like Java REST frameworks (e.g. Jersey) (e.g. Supply „1“ turns into http://myhost:50000/.../Partner/1 )

*)Note! This feature is restricted to certain SP Levels (see SAP Note ) . However we have a workaround for older versions ;)))


And dynamic resource uri‘s by calling a RESTful servcie?


And dynamic resource uri‘s by calling a RESTful servcie?

As in previous example stated anything can be set Dynamic (in a Message Mapping) Static (in a Channel Configuration) Or both combined

URLs, URIs, Resource Ids, Host, Port, etc...

RESTful Adapter - Resources

How are different calls to a resource grouped in an PI interface?



3 different ways to do it, group by: 1 Interface per resource (e.g. Simple CRUD) that responds to all HTTP Methods on

this resource („Method oriented“)

1 Interface hosts several resources and responds to all HTTP Methods below one base path („API oriented“)

Generic: Just receive anything below one base path („Generic“)



E.g. Our example Partner resource with CRUD methods

Service Interface: PartnerOperations:POST (Request/Response)GET (Request/Response)PUT (Request/Response)DELETE (Request/Response/Fault*)

/<baseURI>/Partner

Bound bychannel

*) Faults are not mandatory but usable if needed to cover fault replies from receiver adapters

RESTful Adapter – Errors & HTTP Status

And how about PI faults & system errors?

RESTful Adapter – Erros & HTTP Status


Few facts first: RESTful HTTP Status treatment and PI internal

Success/Errorhandling differs! PI: Response(happy Path), (defined) Faults & System Erros on

Transport RESTful: Plain HTTP Status Code

RESTful Adapter – Erros & HTTP Status


The adapter closes this gap by: Enable you to return any http status in published Services from

regular response or fault messages (System Errors default to 500, but could be overriden)

Enable you to receive any http status for inspection / usage as regular response message from a receiver channel (or by your choice as fault or system error)

RESTful Adapter - JSON

And how about JSON ?

RESTful Adapter - JSON

And how about JSON ?

Any JSON input or output is available as XML internally in PI

The next few examples show the 2 different ways to do it to: Work XML „centric“ or Work JSON „centric“


.. JSON „XML centric“ example!

JSON XML{ "tns:company": { "@xmlns:tns": “urn:my:comp", "name": "My Company", "address": { "city": "München", "zipCode": "83503", "houseNumber": "93a", "country": “DE" } }}

<?xml version="1.0" encoding="UTF-8"?><tns:company xmlns:tns=“urn:my:comp"> <name>My Company</name> <address> <city>München</city> <zipCode>83503</zipCode> <houseNumber>93a</houseNumber> <country>DE</country> </address></tns:company>

This is forth & backward compatible!


.. JSON „JSON centric“ example!

JSON XML[ "1", "2„, 3 ]

<?xml version="1.0" encoding="UTF-8"?><a class="array"> <e type="string">1</e> <e type="string">2</e> <e type="number">3</e></a>

This is forth & backward compatible!

RESTful Adapter - Operations

And how about operations & monitoring?

RESTful Adapter - Operations

And how about operations & monitoring?

Channels can adjust log levels to show http information None, only headers or all (see below)

Payload

Headers

Method & URI

RESTAdapter - Security

What Security standards are supported?

Basic Authentication NTLM 1.x/2.x SSL Client Certificate oAuth1 / 2

RESTAdapter - Misc

What about other misc HTTP topics?

RESTAdapter - Misc

What about other misc HTTP topics?

E.g.: Posting and receiving Form Posts – fully supported

Fits often as more „natural“ choice

Post File Uploads – fully supported as multipart request Imagine posting a form with documents to start a Process?

RESTful Adapter - Samples

And what Samples do we provide „out of the box“?



Samples for publishing RESTful Example Services:

Publish REST Service in XML/JSON from relational Database (GET/PUT/POST/DELETE, JSON, Location Headers)

REST Form POST Request



Samples how to invoke RESTful Sample Services:

Call Twilio SMS API (JSON, Form Post, AuthToken)

Call LinkedIn API (oAuth1, JSON/XML)

Call Salesforce API (oAuth2, JSON/XML, PATCH Method)

RESTful Adapter

Interested in our SAP Certified offer?

We are pleased to hear your feedback

30 Day trial of the adapter available!

RESTful Adapter

Interested in our SAP Certified offer?

Contact us at :

WWW: http:www//kate-group.com/ T +49 711 90 79 64 65 F +49 711 90 79 64 66 E [email protected]

Date post:	16-Dec-2014
Category:	Technology
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KaTe RESTful adapter for SAP Process Integration: Introduction

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