template languages for openstack - heat and tosca

Template Languages for OpenStack

Shay Naeh and Yaron Parasol

About Us

• Shay Naeh – Senior Solution Architect, GigaSpaces

• Yaron Parasol – VP of Product, GigaSpaces– @yaronpar on twitter

Meet the Cast

• HOT – Heat Orchestration Template– Declarative– YAML

• TOSCA– Topology & Orchestration Standard for Cloud

Application– Declarative & Imperative– XML and now YAML

History

• HOT– Came to replace Cloud Formation syntax– Main use case in mind – Infrastructure creation– Following the Cloud Formation limited model

• TOSCA– Application centric by design– Automation of any production process

Similarities

• Similar structure:– Description– Input parameters– Components graph– Output parameters

• Components Design– Component is an object of type– It has dependencies on other components– It has configuration / initial state in the format of

properties

Mutual Influences

• TOSCA adopted HOT Input and Output parameters (coming from Cloud Formation)

• HOT added software_config provider to describe application stack explicitly

• HOT adopted TOSCA relationship syntax and semantics

Differences• Lifecycle

– HOT has limited lifecycle events model• post create hook for installation

– TOSCA using interfaces has lifecycle hooks for node and for relationship node

• Wiring and Validation - Requirements and Capabilities– HOT doesn’t have wiring beyond explicit relationship and parameters injection through

user data– TOSCA – has the mechanism of requirements and capabilities for fine grained wiring

and validations

• Support of Workflows– HOT is 100% declarative. The WF is hardcoded into Heat engine– TOSCA using interfaces allow for any imperative workflow as the driver of processes

(No hard coded processes)

Putting it all together

• TOSCA to HOT translator project:– Developed outside of stackforge but coming in soon– Contributors: IBM, GigaSpaces, Huawei and others – Allow users to describe their stack in TOSCA and use

HEAT• Cloudify – Holistic approach to application

automation on Openstack– Uses TOSCA (currently TOSCA like) templates– Soon to use HEAT to orchestrate infrastructure– Adds: Monitoring, Log collection, Analytics, workflows

DEEP DIVE

Topology

Infrastructure

Middleware

Application

Host Host Network

Apache Tomcat MySQL

Mod_proxy WAR Schema

TOSCA in a Nutshell

Sugar CRM Example

HOT

Type

Lang

uage

Type

sTe

mpl

ates

OS::Nova::Server OS::Heat::software_config

Sugar_CRM_VM Sugar_CRM_App

Sugar_CRM_DB

apache

mySQL

RelationshipScript

Depends_on

Hosted_on

Connects_to

TOSCA Input

Hot Input

TOSCA Node

HOT Component & Resource

TOSCA Requirements

TOSCA Relationship

HOT Relationships

DEMO

Heat Template

Heat Topology View

Apache Server DB Server

NodeJS

NodeCellerMongoDB

TOSCA (Like) Example• App Network• App Subnet• App Port• Security Group• Apache Floating IP• Router Gateway

• Data Network• Data Subnet• Data Port• Security Group

Router

Monitoring, Logging CI

Network View

Topology View

TOSCA (Like) Blueprint

References

• Wine cellar example– https://github.com/cloudify-cosmo/

cloudify-nodecellar-openstack• Cloudify 3– http://getcloudify.org