WSO2 Private PaaS is a multi-tenant Platform as a Service that provides core services like multi-tenancy, logging, identity management, and analytics. It allows SaaS applications to fulfill requirements from both a consumer and provider perspective such as isolation, availability, scalability, personalization, and costs. Non-Carbon applications on WSO2 Private PaaS can achieve some level of multi-tenancy by maintaining separate instances for each tenant, while Carbon-based applications can leverage APIs for identity, security, caching, and retrieving tenant context. The document recommends using WSO2 Private PaaS to develop the survey application due to its support for multi-tenancy and other capabilities required of a

1. Building Multi-tenant SaaS Apps using
WSO2 Private PaaS
Sameera Jayasoma
Software Architect
WSO2

2. SurveyDonkey
> Hello WSO2, We are building a Survey application
and looking for a platform to deploy it. Let me give
you more details of our Survey application.

3. Survey Application
• Enables customers design the survey, publish the survey and collect
results.
• Upon subscribing, customers will get their own space in the
application where they will personalize the look and feel.
• Customers will have different levels of access to the features of this
application, depending on the package they select during
subscription.
• Administration and configuration task are “self-service” and
performed by the customer.
http://msdn.microsoft.com/en-us/library/hh534482.aspx

4. > We got just the thing you want.
> You are building a multi-tenant SaaS
application. We would recommend you to
use WSO2 Private PaaS here
> Why do we need a PaaS?
> Why can’t we simply develop this
application and deploy in a cluster of
Appserver instances in the IaaS layer.
SurveyDonkey

5. > Look, SaaS application has its own unique goals
and requirements.
> They are different from building traditional
web applications.
> We can categorize these requirement in the
perspective of the SaaS application provider and
the SaaS application consumer.

6. Requirements of a SaaS application
Consumer’s perspective:
• Isolation - Tenants want the application to appear as though they are
exclusively using it.
• Availability - Guaranteed SLA. Other tenant activities should not affect the
availability
• Scalability - Application should meet a tenant’s demands no matter what
level resource optimization is in place
• Personalization - Ability to customize the application in various ways.
• Costs - Cost should be much less than running a dedicated hardware

7. Requirements of a SaaS application
Provider’s perspective:
• Achieving tenant’s requirements
• Resource Optimization
• Billing and Metering
• Monitoring
• Self-service
• Maintainability

8. Why you need a PaaS
• PaaS makes it easy to deploy, run and scale applications.
• PaaS gives unlimited language and framework support for
application developers.
• PaaS provides core services such as multi-tenancy, logging,
repository, identity management, elasticity etc..
• PaaS allows applications to be deployed in variety of IaaS
offerings

9. > You can fulfill most of these requirements if you use WSO2
Private PaaS to develop and deploy your application.
> IaaS alone cannot fulfill all these requirement of a SaaS
application.
> Or else you can implement all the features from the scratch.
But I don’t think thats your core business.
> You need to build your Survey application as fast as you can
and gain a competitive advantage.

10. > Let me give a brief introduction to WSO2 Private
PaaS as well to its architecture. Then I will explain
how a SaaS application can leverage capabilities
offered by WSO2 Private PaaS.
> Okay. Can you show how WSO2
Private PaaS will helps us achieve all
the necessary requirements?
SurveyDonkey

11. WSO2 Private PaaS
• Complete, multi-tenant, self-service, metered middleware
cloud for enterprise ready projects.
• Provides
• application,
• data,
• integration,
• identity,
• governance and
• analytics
Platform as a Service
• Built on top of Apache Stratos

12. WSO2 Private PaaS - Layered Architecture

13. SaaS Apps with WSO2 Private PaaS
Application Application Application Application SaaS
PaaS
IaaS

14. Cartridges
A Package of Code that plugs into WSO2 Private PaaS to offer a
new PaaS service.
PHP
Cartridge
WSO2 ESB
Cartridge
Single-tenant Cartridge.
Stratos will run and manage a separate instance for each
tenant.
Multi-tenant Cartridge.
Stratos will run multiple instances of partitions so that
sets of tenants run on sets of instances.
Build to the metal - these servers are written from the
scratch to be multi-tenant.

15. > Multi-tenancy is all about isolation.
> A multi-tenant solution should provide
isolation is many aspects. Let me explain.
> Now that you mention multi-tenancy,
how can I achieve tenant level isolation
when developing applications on top of this
WSO2 Private PaaS?
SurveyDonkey

16. Multi-tenancy is about isolation
• Data
• Configuration information
• Database
• User Interface
• Customizations
• Metadata
• Logs

17. Carbon Multi-tenant Architecture

18. How to Achieve Tenant Isolation
• Each tenant is given a security domain
• Each domain may have its own userstore and permissions.
• Each domain is isolated and do not have access to other domains.

19. How to Achieve Data Isolation

20. > There are a bunch of APIs.
Let me briefly explain some
useful APIs.
> Okay. If I am building my
application on top WSO2 Carbon
server Cartridges then what are the
available Java APIs?
SurveyDonkey

21. Carbon APIs
• Identity and Security API - Manage users, roles, permission,
authentication and authorization functionalities
• Registry/Repository API - crud api for repository.
• Caching API - Java caching API

22. Carbon APIs..
• CarbonContext API - CarbonContext is the entity which provides the
runtime related contextual information of the current executing
thread.
• Any code running in Stratos can retrieve following information from
the CarbonContext API.
a. Tenant information who is executing the code.
b. Logged in user information, if any.
c. Application information, if any.

23. > If I am using non WSO2 Carbon server
cartridges then how can I achieve multi-
tenancy.
> How can I use above mentioned APIs?
SurveyDonkey

24. > If you are planning to use non WSO2 Carbon servers like Tomcat,
JBoss, PHP then you will have to maintain an instance of these
servers per tenant.
e.g. each and every tenant will have a separate PHP instance.
> You will have limited options, if you want to access those APIs
that I’ve described in the previous slides.
> But we do have certain exposed REST APIs, let me list them down
for you.
> We are in the process improving these APIs.

25. APIs available for non Carbon based Apps
• APIs available to communicate with the connected Userstore
• Tenant-mgt REST API to get tenant information. This APIs is available in the Stratos
Manager.
• Admin Services in Stratos Manager. These are Carbon level APIs. Can extract necessary
information.

26. > Use bizdev@wso2.com for business
related matters.
> For technical information you
following open lists.
architecture@wso2.org
dev@wso2.org
> Thanks WSO2. How can I contact
you for more information?
SurveyDonkey

27. Thank You