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table of contents

scaling your webapp
10 Getting real

The Web is a great place to host your app…until things get real.
Sooner or later, you’ll hit the jackpot and your webapp will be wildly successful. When
that happens, your webapp goes from a handful of hits a day to thousands, possibly ten
of thousands, or even more. Will you be ready? Will your web server handle the load?
How will you know? What will it cost? Who will pay? Can your data model scale to
millions upon millions of data items without slowing to a crawl? Getting a webapp up and
running is easy with Python and now, thanks to Google App Engine, scaling a Python
webapp is achievable, too.

There are whale sightings everywhere 352
The HFWWG needs to automate 353
Build your webapp with Google App Engine 354
Download and install App Engine 355
Make sure App Engine is working 356
App Engine uses the MVC pattern 359
Model your data with App Engine 360
What good is a model without a view? 363
Use templates in App Engine 364
Django’s form validation framework 368
Check your form 369
Controlling your App Engine webapp 370
Restrict input by providing options 376
Meet the “blank screen of death” 378
Process the POST within your webapp 379
Put your data in the datastore 380
Don’t break the “robustness principle” 384
Accept almost any date and time 385
It looks like you’re not quite done yet 388
Sometimes, the tiniest change can make all the difference… 389
Capture your user’s Google ID, too 390
Deploy your webapp to Google’s cloud 391
Your HFWWG webapp is deployed! 394
Your Python Toolbox 395

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