(Cloud) Services: An Introduction to TOSCA (Topology and Orchestration Specification for Cloud Services)

(Cloud) Services:An Introduction to TOSCA

(Topology and Orchestration Specification for Cloud Services)

Gerd BreiterFrank LeymannSimon Moser

Thomas Spatzier

Terminology

2

Caution: Terminology

SOA and Systems Management…

…use the terms “service”, “composition”, “orchestration”,… differently

…at least with different foci

3

Terminology: Service

“Service” means different things In SOA: Any kind of (reasonably coarse-grained)

application function Interesting discussion: what is an application? It depends on the

domain… In Systems Management: Any kind of resource and

appropriate actions required to support business with IT Interesting discussion: systems management is an application too.

Thus, the SOA notion of service applies too – but that might get confusing at this point in time

4

Terminology: Orchestration

“Orchestration” means different things In SOA: the aggregation of application functions into

higher level business functions In Systems Management: the proper sequencing of

individual management tasks to manage complex IT artifacts

YES: both can be done with the same underlying technology (BPMN, BPEL,…) but the focus is very different

5

Terminology: Composition

“Composition” means different things In SOA/SCA: the aggregation of application functions and

their relations for the purpose of proper deployment In Systems Management: the “parts tree” of complex IT

artifacts for the purpose of setting up the artifacts correctly, as well as the processes for ensuring the appropriate continuous management of the artifacts

6

Conceptual Overview

7

Imagine…

…that you have a nice application that you want to be able to be hosted in different clouds

Why do you want that? Because you don’t want to be locked into the platform of a

single cloud provider, or Because you start in your own private cloud and want to

be able to move it to public cloud or to some community cloud or to hybrid cloud

8

CloudProvider A

CloudProvider B

3. Move (i.e. Provision)

1. Provision& Manage

4. Use

5. Manage

Thus, the Scenario is:Moving Cloud Applications

9

2. Use

What are the Technical Problems?

No interoperable description exists of what your application is and what it requires Virtual images do not suffice at all

They are “just” snapshots of the actual state of your application Another provider might not have a clue how to install,

deploy, run & manage your application Deep detailed skills about the application and its

underlying stack is needed that “arbitrary” providers typically don’t have

10

What Is “(Cloud) Service Template” All About?

A new language (“metamodel”) to specify the building blocks of your application the management functions these

building blocks offer to be managed

the relations between these building blocks

Collection of node types and relationship types(for reuse purposes)

the procedures to follow in order to manage your application as a whole 11

NodeTypes

Rel.shipTypes

Plans

Topology(Template)

(Clo

ud) S

ervi

ce Te

mpl

ate

GroupTemplate

Graphical Representation

12

Prop

ertie

s Interfaces

NodeTemplate

Topology Template

type for

Node Type

Relationship Template

Service TemplateNode Types

Plans

type for

Prop

ertie

s Relationship TypeRelationship Types

GroupTemplate

…and More Colorful…

13

Topology Plans

…and With Angular Brackets…

14

<ServiceTemplate …> <Extensions/>? <Import />*

<Types/>?

( <TopologyTemplate/>

| <TopologyTemplateReference/>)?

<NodeTypes/>?

<RelationshipTypes/>?

<Plans/>? </ServiceTemplate>

Example: High Level View

15

WebSphereCell

DB2 Server

WebSphereProcessServer

BPEL Files

EJBs

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn…and this is a bit more clomplex…

Node Template


Example: WebSphere Cell Refined

16

WebSphere Cell

IHSNode

WAS NDDeployMgr

Node

WAS NDManaged

Node

Application Server

Instance

Cluster

DB2 Server

DB2 Database Instance

"cluster""database"

1..*

1..*exists

Properties, e.g.:ports, servername, weight

Properties, e.g.:WAS install location, Profile name, Node name

WebSphereCell

DB2 Server

Example: Overall Topology Template

17

WebSphere Cell

IHSNode

WAS NDDeployMgr

Node

WAS NDManaged Node

Application Server Instance

Cluster

DB2 Server

DB2 Database Instance

1..*

1..*


BPEL Files

EJBs

WSDL Files

Example: Amazon

18

WebSphereCell

DB2 Server


BPEL Files

EJBs

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn

Amazon

…Which is the “Interoperable Service Templates” Scenario (see later)

19

WebSphereCell

DB2 Server


BPEL Files

EJBs

WSDL Files

Amazon

Example: Amazon – Refined Scenario

20

WebSphereCell

DB2 Server(WAS Data)


BPEL Files

EJBs

WSDL Filesuses

Implemented by deployedOn

requires

requires

Amazon

DB2 Server(Application

Data)

requires

WebSphereCell

deployedOn

On Premise

Example: Amazon – Refined Scenario(Details)

21

WebSphereCell

DB2 Server(WAS Data)


BPEL Files

EJBs

WSDL Filesuses

Implemented by deployedOn

requires

requires

Amazon

DB2 Server(Application

Data)

requires

WebSphereCell

deployedOn

On Premise

The Web Services required by the BPEL processes are hosted on premise

The EJBs (e.g.) implementing the Web Services are deployed on WebSphere hosted on premise

The application data of the WS/EJBs are stored in DB2 on premise

This ensures compliance with data privacy/confidentiality rules

Process Server etc is installed and managed at Amazon’s EC2

The corresponding middleware is provided as AMIs

The process models are deployed on Process Server

Process Server maintains state data in DB2 also running in EC2

Example: Reusing Existing Services

22

Only the processes and required middleware is managed on a “known” cloud

The Web Services needed by the BPEL processes are reused “wherever” they are

The existing Web Services are bound to the BPEL process by the established mechanisms

Specifying binding details can be part of the build plan of the application’s Service Template (.ste)

WebSphereCell

DB2 Server


BPEL Files

WSDL Files

uses

deployedOn

requires

requires

deployedOn

WS1

WS2

WSn

…

„somewhere1“

„somewhere2“

„somewheren“

boun

d to

Example: SAP

23

Netweaver

Oracle

SAP Workflow

BPEL Files

EJB

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn

SAP

Example: Microsoft

24

.Net

SQL Server

BizTalk

BPEL Files

.NetAssemblies

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn

Azure

Example: Different Hosters of a Particular Application

25

Netweaver

Oracle

SAP Workflow

BPEL Files

EJB

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn

IBM

AT&T

T-Systems

...

…Which is the “Market for Cloud Applications” Scenario (see later)

26

Netweaver

Oracle

SAP Workflow

BPEL Files

EJB

WSDL Files

uses

implementedby

deployedOn

requires

requires

deployedOn

deployedOn

IBM

AT&T

T-Systems

...

Sample:Websphere Management Plans

27

Provision Dmgr

Enable Admin

Security

Start Dmgr

Create Cluster

Provision Managed Node

Federate Node

DeployMon. Agent

Create Cluster

Members

Provision IHS Node

Deploy Mon. Agent

(IHS)Start IHS Configure

WebserverStart

Cluster

Deploy Monitoring

Agent (Dmgr)

Provision Managed Node

Federate Node

DeployMon. Agent

Create Cluster

Members

Start Cluster

Unfederate Node Reconfigure

Webserver

RemoveMon. Agent

Deprovision Managed Node

InitialProvisioning

Add Nodes

Remove Nodes

How Plans and Nodes Fit Together

Task of a plan refers to interface of a topology node

Topology node specifies all interfaces offered to manage it

Interface is bound to a concrete implementation

Implementation already available at providers side, or Implementation is copied from somewhere, or A standardized Cloud Interface (Iaas, PaaS, SaaS) is used,

or ...

28

WebSphere Cell …

Create Cluster

… …

Script- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

…refers to…

…bound to…

A Caveat!

The “(Cloud) Service Template” spec is not (!) about standardizing topologies and plans for a series of concrete products

The “(Cloud) Service Template” spec is (!) about standardizing the language that can be used to precisely describe topologies and plans for concrete products

Various products (i.e. their topologies and plans) can be standardized base on that at a later time By various domain experts, vendors,…

29

Baseline

TOSCA is modular and composable

It does not reinvent the wheel, i.e. it uses existing standards wherever possible E.g. WSDL, BPMN, OVF,…

30

Motivation

31

CloudProvider A

CloudProvider B

4. Move

Service Template

Service InstanceService Instance

Service Template

1. Build

2. Use 3. Want Use

5. Build

6. Use

Scenario 1:Mobility of Cloud Applications

32

Important Note

TOSCA deals with interoperability of Service Templates here

I.e. portability of the ingredients of an IT Service (especially the code artifacts) is not addressed by TOSCA

Similarly, mobility of data used by a corresponding service instance is not in the scope of TOSCA

33

ServiceCatalog

1. Create

2. Publish

3. Browseand Select

4. Provision

5. Use

Service Template

Service Instance

Scenario 2: Creating a Market For Cloud Applications

34

CloudProvider A

Realized By

Implemented As

CloudProvider C

CloudProvider B

Scenario 3:Interoperable Service Compositions

35

Scenario 4:Using OVF Packages

36

Note: only subtree of servicedefinition relates to OVF, othersubtrees/nodes can point toshared resources (e.g. DB2,…)

<ovf:Envelope ... > <ovf:VirtualSystemCollection...>

<ovf:VirtualSystem ... > ... <ovf:ProductSection ... > ... </ovf:ProductSection ... > ... </ovf:VirtualSystem>

<ovf:VirtualSystem ... > ... </ovf:VirtualSystem>

...

</ovf:VirtualSystemCollection></ovf:Envelope>

Refined View

37

How ...

------------

------------

------------

OVF OV

FOVF

With ...Scripts WorkflowsEAR (EJBs,…)BPEL

The images of the middleware (DB2, Websphere,…) required to run the application

The business logic of the application, e.g. EJBs, JSPs, JPEG,…

The business processes of the application (BPEL, BPMN, Human Tasks,…)

(Existing) scripts used by task of plans to manage the cloud application

(Existing) workflows used by subprocess-tasks of plans

Service

Cloud Management & Orchestration

38

SaaS

Server Server Storage

AppSrv DB

Application

PaaS

IaaS is maturing. Evolution of standards like OVF or defacto standards like EC2 or S3 enable growth of ecosystems.

PaaS offerings exist (e.g. MicroSoft Azure), but are restricted solely to the PaaS layer.

SaaS offerings exist (e.g Google Apps), but as standalone offerings restricted to the SaaS layer.

Interfaces between PaaS and IaaS starting to evolve.

Components in a composite service can come from one Cloud, multiple Clouds, or can be non-Cloud resources (e.g. existing company LDAP or private DBs).

Man

agem

ent

Scop

e

Management Functionality

Deploy, Decommission

Start, Stop, Resize

Management Plans covering the complete service life cylce.

IaaS

CloudManagement & Orchestration

Service Template: Specification Overview

39

Ingredients of a Service Template

40

Prop

ertie

s Interfaces

NodeTemplate

Topology Template

type for

Node Type


Service TemplateNode Types

Plans

type for

Prop

ertie


GroupTemplate

Structure of .ste Document

41

<ServiceTemplate id="ID" name="string" targetNamespace="anyURI"> <Extensions/>? <Import />* <Types/>? ( <TopologyTemplate/>| <TopologyTemplateReference/>)? <NodeTypes/>? <RelationshipTypes/>?

<Plans/>? </ServiceTemplate>

Topology Template

Node Types

Relationship Types

Plans

Node Types: Overall Structure

42

<NodeTypes>? <NodeType id="ID" name="string">+ <NodeTypeProperties element="Qname"? type="QName"?/>? <DerivedFrom nodeTypeRef="QName"/>?

<InstanceStates/>? <Interfaces/>? <DeploymentArtifacts/>? <Policies/>? </NodeType> </NodeTypes>

Prop

ertie

s Interface

Node TypeNode Types

Interfaces of Node Types

43

<Interfaces>? <Interface>+ ( <WSDL portType="QName“ operation="NCName">+ | <REST method="GET | PUT | POST | DELETE" requestURI="anyURI" requestPayload="QName"? responsePayload="QName"?>+ | <Operation name="NCame">+ <InputParameters>? <InputParamter name="string" type="string" required="yes|no">+ </InputParameters> <OutputParameters>? <OutputParamter name="string" type="string">+ </OutputParameters> <Implementations> <Implementation implementationID="anyURI"? language="anyURI"?>+ ( <ImplementationProper>? code </ImplementationProper> | <ImplementationReference ref="anyURI"/>? ) <Implementation> </Implementations> </Operation> ) </Interface> </Interfaces>

Interfaces

Deployment Artfactsof Node Types

44

<DeploymentArtifacts>? <DeploymentArtifact name="string" type="anyURI">+ artifact specific content </DeploymentArtifact></DeploymentArtifacts>

Policies of Node Types

45

<Policies>? <Policy name="string" type="anyURI">+ policy specific content </Policy> </Policies>

Example: Node Types

<ServiceTemplate name="myService" targetNamespace="http://www.ibm.com/sample"> <NodeTypes> <NodeType name="Project"> <documentation xml:lang="EN"> A reusable definition of a node type supporting the creation of new projects. </documentation> <NodeTypeProperties element="ProjectProperties"/>

<InstanceStates> <InstanceState state="www.my.com/active"/> <InstanceState state="www.my.com/onHalt"/> </InstanceStates>

...

...<Interfaces> <Interface> <Operation name="CreateProject"> <InputParameters> <InputParamter name="ProjectName" type="string"/> <InputParamter name="Owner" type="string"/> <InputParamter name="AccountID" type="string"/> </InputParameters> <Implementations> <Implementation> ... </Implementation> </Implementations> </Operation> </Interface> </Interfaces> </NodeType> </NodeTypes> </ServiceTemplate>>

Relationship Types

47

<RelationshipTypes> <RelationshipType id="ID" name="string" semantics="anyURI" cascadingDeletion="yes|no">+ <RelationshipTypeProperties element="QName"? type="QName"?/>?

<InstanceStates>? <InstanceState state="anyURI">+ </InstanceStates> </RelationshipType> </RelationshipTypes>

Prop

ertie


Example: Relationship Types

<RelationshipTypes> <RelationshipType name="processDeployedOn" semantics="www.my.com/RelSemantics/procDeployedOn" cascadingDeletion="yes"> <RelationshipTypeProperties element="ProcessDeployedOnProperties"/> <InstanceStates> <InstanceState state="www.my.com/successfullyDeployed"/> <InstanceState state="www.my.com/failed"/> </InstanceStates>

</RelationshipType> </RelationshipTypes>

<TopologyTemplate id="ID" name="string"?> ( <NodeTemplate/> | <RelationshipTemplate/> | <GroupTemplate/> )+ </TopologyTemplate>^

Topology Template

49

Node Template

…type for…


…type for…

GroupTemplate

Topology Template (cont.)

50

<TopologyTemplate id="ID" name="NCName"> ( <NodeTemplate id="ID" name="string" nodeType="QName" minInstances="int"? maxInstances="int|string"?>+ <PropertyDefaults>? XMLDocument </PropertyDefaults> <PropertyConstraints>? <PropertyConstraint property="string" constraintType="anyURI">+ constraint? </PropertyConstraint> </PropertyConstraints> <Policies/>? <EnvironmentConstraints>? <EnvironmentConstraint constraintType="anyURI">+ constraint type specific content? </EnvironmentConstraint> </EnvironmentConstraints> <DeploymentArtifacts/>? </NodeTemplate> | <RelationshipTemplate/> | <GroupTemplate/> )+ </TopologyTemplate>

Node Template

…type for…


…type for…

GroupTemplate


51

<TopologyTemplate id="ID" name="NCName"> ( <NodeTemplate/> | <RelationshipTemplate id="ID" name="string" relationshipType="QName">+ <SourceNodeElement id="IDREF"/> ( <TargetNodeElement id="IDREF"/> | <TargetNodeTemplateReference name="QName"/> ) <PropertyDefaults/>? <RelationshipConstraints>? <RelationshipConstraint constraintType="anyURI">+ constraint? </RelationshipConstraint> </RelationshipConstraints> </RelationshipTemplate> | <GroupTemplate/> )+ </TopologyTemplate>

Node Template

…type for…


…type for…

GroupTemplate


52

<TopologyTemplate id="ID" name="NCName"> ( <NodeTemplate/> | <RelationshipTemplate/> | <GroupTemplate id="ID" name="string"? minInstances="int"? maxInstances="int|string"?> ( <NodeTemplate ... /> | <RelationshipTemplate ... /> | <GroupTemplate ... /> )+ <Policies/> </GroupTemplate> )+ </TopologyTemplate>

Node Template

…type for…


…type for…

GroupTemplate

Example: Service Topology Template

<ServiceTemplate name="myService" targetNamespace="http://www.ibm.com/sample" xmlns:abc="http://www.ibm.com/sample"> <Import namespace="http://www.ibm.com/sample" importType=" http://www.example.org/STE"/> <TopologyTemplate name="VirtualServerProject"> <NodeTemplate id="myProject" nodeType="abc:Project"> <PropertyDefaults> <ProjectProperties> <Owner>Frank</Owner> <ProjectName>Thomas’ favorite project</ProjectName> </ProjectProperties> </PropertyDefaults> <NodeTemplate/>

<NodeTemplate id="myVirtualServer" nodeType="abc:VirtualServer" minInstances="0" maxInstances="unbounded"/> ...

…

<RelationshipTemplates> <RelationshipTemplate name="myRelationship" relationshipType="contains"> <SourceNodeElement id="myProject"/> <TargetNodeElement id="myVirtualServer"/> </RelationshipTemplate> </RelationshipTemplates> </TopologyTemplate> </ServiceTemplate>

53

Plans

54

<Plans> <Plan id="ID" name="string"? planType="anyURI" languageUsed="anyURI">+ <PreCondition expressionLanguage="anyURI">? condition </PreCondition> ( <PlanModel> actual plan </PlanModel> | <PlanModelReference reference="anyURI"/> ) </Plan> </Plans>

Plans

Example: Plans

...

<Plan id="RemoveApplication" planType= "http://www.example.org/STE/PlanTypes/TerminatioPlan" languageUsed= "http://docs.oasis-open.org/wsbpel/…/executable"> <PlanModelReference reference="prj:RemoveApp"/> </Plan> </Plans>

<Plans> <Plan id="DeployApplication" name="Sample Application Build Plan" planType= "http://www.example.org/STE/PlanTypes/BuildPlan" languageUsed="http://www.omg.org/spec/BPMN/2.0/"> <PreCondition expressionLanguage="www.my.com/text">? Run only if funding is available </PreCondition> <PlanModel> <process name="DeployNewApplication" id="p1"> <task id="t1" name="CreateAccount"/> <task id="t2" name="AcquireNetworkAddresses" isSequential="false" loopDataInput="t2Input.LoopCounter"/> <sequenceFlow id="s1" targetRef="t2" sourceRef="t1"/> ... </process> </PlanModel>

...

Scenario

56

Sample Node Type: SuperStorage

<xs:element name="StorageProperties"> <xs:complexType> <xs:sequence> <xs:element name="TotalStorageAmount" type="xs:string"/> <xs:element name="IPAddress" type="xs:string"/> … </xs:sequence> </xs:complexType> </xs:element>

<NodeType name="SuperStorage"> <NodeTypeProperties element="StorageProperties"/> <Interface> <Operation name="CreateStorageContainer"> <REST method="POST" … <Operation name="AddFile"> <REST method="PUT" … … </Interface> </NodeType>

Vendor „BestStorageVendor“ Sells ist Devices with Corresponding Node Template

BestStorageVendor defines Node Template to specify its BestStorageDevice based on former Node Type

Vendor sets Properties that are known from the outset TotalStorageAmount is known IPAddress is set during installation/deployment

Implementation of interface is referenced from Node Template

<NodeTemplate name="BestStorageDevice" nodeType="SuperStorage"> <PropertyDefaults> <TotalStorageAmount>1000TB</TotalStorageAmount> </PropertyDefaults>

<DeploymentArtifacts> <DeploymentArtifact name="InterfaceImplementation" type="WARref">

... </DeploymentArtifact> </DeploymentArtifacts>

</NodeTemplate>

Customer Deploys New Device

.......

.....

Service Template Deployment Artifacts

StorageAPI.war

…

TOSCAContainer

TOSCADatabase

1

2

3

StorageAPI.war

1. IPAddress-Property of Device is set2. StorageAPI.war is deployed

• IP address of Servlet Container is set3. IP-Address of Servlet Container becomes HOST header for REST API

Tasks of Plans are Deployed

BestStorageDevice

…

CreateStorage

… …

1. refers to…

3. values from…

TOSCADatabase

<NodeTemplate name="BestStorageDevice" nodeType="SuperStorage"> <PropertyDefaults> <TotalStorageAmount>1000TB</TotalStorageAmount> </PropertyDefaults> <NodeType name="SuperStorage"> <Interface> <Operation name="CreateStorageContainer"> <REST method="POST" …

CreateStorageContainer

StorageAPI.war

2. requires data…

4. locates code…

End of Document

61

Documents

(Cloud) Services: An Introduction to TOSCA (Topology and Orchestration Specification for Cloud Services)