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API-First: Going Beyond SOA, ESB, and IntegrationEd Anuff, Apigee

Brian Pagano, Apigee

@edanuffEd Anuff

@brianpaganoBrian Pagano

What do we mean by APIs?

The A in API is for apps

Rich clients(Visual Basic, Delphi, etc.)

Thin clients(Web Applications)

Rich clients(Mobile Apps)

App

HTTP

Browser

App

InternalExternal

App

Modern server-side app

•Often runs in an app server•Monolithic presentation and business logic•Hosted in an environment(often a virtualized container)• Increasingly lightweight

BackendAPI

App

Apps need resources

•Databases and storage•Email services•Sometimes integration-based,but increasingly API-based

APIs are not SOA++

Cloud business services

•Database-as-a-Service•Storage-as-a-Service•Email-as-a-Service•MQ-as-a-Service

•All are already in widespread use …

Internal resources

•Many new resource services already are API-based•Developers prefer to use APIs even with the added work of learning APIs versus ESB approaches

SDK

API

Mobile API architecture

CC-BY-SA

Device-sideapplogic

Server-sideapplication logic &

infrastructure

Sometimes apps talk to other apps

API

Front end

BackendAPI

App APIAPI AppApp

InternalExternal

App-to-app

•API-centric: app developers expose their own APIs and learns others’ APIs• Integration: normalized data interchange•Agility trade-off

API

Front end

BackendAPI

AppAPI

API

Partner App

3rd Party App

InternalExternal

Okay, we have to talk about microservices

Internal

API

Front end

BackendAPI

APIAPI AppAppServic

eServic

eServic

e

Service

Service

Service

Service Service Service

APIs

APIs

Microservice architecture

External

Microservices

•Components are services, not in-process objects•Allows polyglot programming•Easier to scale component services individually

Evolving toward API-first

Monolithic web app

Web apps

App server

Backend services

API-adapted Web AppsConsumption-focused Web Apps

App Server

Backend Services

Other apps

API

API-adapted SOAExposure-focused

Web apps

App server

Internalservices

Other apps

API

ESB

API-first enterprise

Web apps

App servers BackendservicesESB

Mobile apps

API tier

All apps

Security AnalyticsPersistence Orchestration

Other apps

What comes next?

API mass customization

App “B”

App servers BackendservicesESB

App “A”

API Tter

App “C”

API “B”API “A” API “C”

API tier analyticsAll channels

API Tier

All backends

All interactions

Analytics

CorrelationsCohortsConversionsSegmentationA/B & multivariate

API tier with analytics

• API adaptations needed for apps• Enable developers for business• Security for app-to-API• App and behavior analytics

• APIs architected for abstraction• Enable developers for API use• Security for API-to-backend• API analytics

APIAPI

App consumption API exposure

App server ServicesApp

Analytics

Summary

•“A” is for Apps•APIs are not SOA++•Microservices?•How to get to an API-centric architecture