Google App Engine Danail Alexiev Technical Trainer SoftAcad.bg

Who’s Talking? Danail Alexiev o Software Consultant at Axway, technical trainer at SoftAcad learning center

Topics Today What is Google App Engine(GAE) ? Why GAE ? Architecture of GAE Quota & Pricing Developing using GAE Deploying Applications Security GAE datastore Demo application

What is GAE? Google’s platform to build Web Applications on the cloud Dynamic Web server Transactional DataStore Model

Why GAE? Automatic scaling and load balancing Lower total cost of ownership Web administration console & utilities Enhances developing & deploying of web applications Multilanguage support (Java, Python, GO..) Secure environment (Sandbox)

Architecture of GAE

Quota & Pricing $ $0.12 per CPU core-hour $ $0.18 per GB-month of storage $ $0.13 per GB outgoing bandwidth $ $0.11 per GB incoming bandwidth

Developing using GAE Dynamic web serving o With full support for common web technologies Persistent storage o With queries, sorting and transactions Automatic scaling and load balancing Google Account APIs o For authenticating users and sending A local development environment o That simulates Google App Engine on your computer Task queues o For performing work outside of the scope of a web request Scheduled tasks for triggering events

The Sandbox Outgoing access via URL fetch or services Incoming access via HTTP (or HTTPS) Store state via App Engine datastore, memcache Respond to web request, queued task, scheduled task Return response data within 30 seconds Quotas and Limits Free 500MB of storage and 5 million page views a month 10 applications per developer account

The GAE Datastore

Intro to DS Apparently based on BigTable Absolutely not a relational database No joins (they do have “reference fields”) No aggregate queries - not even count()! Hierarchy affects sharding and transactions All queries must run against an existing index

Models & Entities Data is stored as entities Entities have properties - key/value pairs An entity has a unique key Entities live in a hierarchy, and siblings exist in the same entity group o These are actually really important for transactions and performance A model is kind of like a class; it lets you define a type of entity

Developing using GAE Hello world Datastore & entities Memcache Mail and Task Queues API High Replication Queues & Backends Warmup requests Pagination

Deployment Deployment Register using admin console if not done yet and get application ID Uploading using eclipse plugin – just click upload! Or using command line : appengine-java-sdk\bin\appcfg.cmd [options]

Google App Engine

Homework 1.Following the GAE tutorial at ava/gettingstarted/creating create and deploy a "Hello World" application in the GAE cloud. ava/gettingstarted/creating 2.Following the official GAE manuals ( java/gettingstarted/) create and deploy a simple guestbook application in Java or Python. java/gettingstarted/ In case you find difficulties, check the solution here: As a result of your work send the source code + the URLs of your working application deployed in GAE.