ow2con'14 - erocci, a scalable, model-based rest api framework

November 5th, 2014 erocci - Jean Parpaillon 1

erocci

A scalable model-driven REST framework

Jean Parpaillon <[email protected]>


REST API : a user point of view



Data formatJSON formatXML formatScalar data types (string, integer, float, etc)

Data access protocolFilteringSortingPaginationAuthnz (tokens, etc), return codes, etc.

Finally...Application level : data types (structures, relations, etc)



Data formatJSON formatXML formatScalar data types (string, integer, float, etc)

Data access protocolFilteringSortingPaginationAuthnz (tokens, etc), return codes, etc.

Finally...Application level : data types (structures, relations, etc)

Schémas ?

One to rule them all ?

A single meta-model ?


Let's speak about a standard ?


Let's speak about a standard for REST

A standardIs not a catalog of schemasIs not a constraint for developersMust be implemented (implementable)

A good standardShould allow to concentrate on the design, not the implementation detailsAllow to build an ecosystemAllow to accelerate the development, not the contrary


The Open Cloud Computing Interface

OCCI is typedA ressource is an instance of a kindA kind is a named list of typed attributes and actions

e.g. : compute : # cores (integer), RAM (float), etc Attribute : name, type, default value, mutability, etc. Action : an invocable operation on a ressource Kinds are inheritable



OCCI is extensibleResource can be associated with mixinsMixin: a named set of additional attributes and actions

e.g. : IPNetworkInterface adds IP, netmask, etc to a network interface

User Mixin : aka « tags » e.g. : http://example.com/occi/mixins#my_project1



OCCI is relationalLinks are ressources with additional attributes

occi.core.source : resource URI occi.core.target : URI

A bounded collection is a list of ressources of the same kind/mixin :

e.g. : GET /collections/compute/ An unbounded collection is a list of ressources with same prefx :

e.g. : GET /myresources/



OCCI is self-describedGET /-/ (capabilities)

List of supported kindsList of supported mixins

Capabilities returns collection's URLhttp://schemas.ogf.org/occi/infrastructure#compute → /collections/compute/

http://schemas.ogf.org/occi/infrastructure#compute



OCCI is meta-model basedModel consistency checkingAutomatic model implementationRendering independant

text/plain, application/json, …Transport independant

HTTP, ...


OCCI Ecosystem

Framework

rOCCI (ruby)

occi4java (not maintained)

Specifc implementations

CompatibleOne

PyOCNI

OpenStack, OpenNebula, etc

Limits

Models are language/extensions/lib dependant

See http://occi-wg/community/implementations/

Tools

DoYouSpeakOcci : tests

Monitoring (Intel)

http://occi-wg/community/implementations/

http://occi-wg/community/implementations/


Why erocci ?

Generic : a framework to build OCCI applications Less code, more designSmall, tested, reliableEasy to deployScalable

Runs embedded in connected objects (IoT)Scales out to serve millions of users

Extensible


Architecture


Genericity

Only OCCI meta-model is hard-codedEverything is pluggable :

Authentication mechanismTransport protocol (HTTP, XMPP, etc)Data sources (backends)

Allow composition of services by plugging data sources (backends) at runtime


Less code, more design

A schema for ressources' categories (kinds, mixins)ACL-based authorizations


Small, tested, reliable

SmallAround 12k lines

TestedContinuous integration

ReliableErlang cowboy web server (LeoFS, MongooseIM, etc)erlang/OTP platform provides fault toleranceProcess supervision


Easy to deploy

All included erlang/OTP platformSelf contained : no web frontend Just try it !


Scalable

Thanks to erlang/OTPRuns on RaspberryPI (~ 100 req/sec)Scales out to a full cluster


Extensible

Pluggable mechanismsFor those who don't like erlang

D-Bus backend API (experimental)


(1) use case : a REST backend for blog

No need for ORM, web server, database, templating, etc.Design your model

Blog entry kindUser kindContribution kind (link between a user and an entry)

Choose a storage backendChoose a transport (HTTP?)Defnes ACLAnd that's all


(2) use case : API adapter

Backend API : write a new data source for your API Erlang APID-Bus API (any language)In any case, implements CRUD operations

Choose a transportEnjoy scalability, supervision, transports, ACL, etc.


(3) use case : a protocol adapter

You have a resource oriented protocol and want to expose it through HTTP/OCCIUse occi_store for storing your dataerocci deals with storage, rendering, scalability, ...


Roadmap

Authn/authzx509 based authnoauth

occi_storeOptimizationsIntegrate authnz, pagination (wip)

XMPPEnable pubsub (notifcations)

New storage backendsRiak (wip)ODBC (SQL)…

TestingImprove functional testsImprove unit testing


Eco-system : OCCIware

(1) consortiumResearch, industry, standardization

(3) pillarsTheory : proven meta-model (OCCI) Design : Eclipse-based tools Runtime : erocci, …

(*) use casesIaaS, PaaS, SaaS, IoT, ...Every RESTful services


Resources

Website (WIP)http://erocci.ow2.org/

Source codehttp://github.com/erocci/erocci

Continuous integrationhttps://travis-ci.org/jeanparpaillon/erocci

Mailing [email protected] / [email protected]

http://erocci.ow2.org/

http://github.com/erocci/erocci

https://travis-ci.org/jeanparpaillon/erocci

mailto:[email protected]

mailto:[email protected]


Thanks !

Questions ?

ow2con'14 - erocci, a scalable, model-based rest api framework

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