Serverless Django with Zappa—DjangoConUS 2018

A common set of considerations when planning to release a new application are around hosting and resources:

* Which platforms will support my app?
* What OS should I use?
* What WSGI server should I use?
* How much memory and CPU do I need?

Zappa, a framework for running serverless WSGI applications on top of AWS Lambda, can help address these and other questions around application deployment. With some configuration (as code), Zappa can get you up and running quickly, letting you focus on developing the application instead of the infrastructure.

In this talk we’ll go through some of these kinds of questions to see how they might be answered in traditional solutions and then see how Zappa handles them. We’ll also talk about a few specific configuration options for handling SSL certificates and running Django commands on the Zappa-deployed application.

Transcript

1. Dane Hillard Web Application Developer, ITHAKA Twitter / easyaspython GitHub / daneah
3. Zappa
4. Serverless Django with Zappa
5. Miserlou/Zappa
6. Miserlou/Zappa A tool for serverless AWS deployment of Python applications
7. Miserlou/Zappa A tool for serverless AWS deployment of Python applications
8. Overview • Server • Less • AWS • Deployment
9. Server
10. Server Request Response
11. Server nginx gunicorn Django assets cert Django Django database
12. load balancer
13. Less
14. nginx gunicorn Django Assets cert Request Response database
15. nginx gunicorn Django Assets cert Request Response database
16. nginx gunicorn Django Assets ACM Request Response database
17. nginx gunicorn Django Assets ACM Request Response database
18. nginx gunicorn Django Assets ACM Request Response database
19. nginx gunicorn Django S3 ACM Request Response database
20. nginx gunicorn Django S3 ACM Request Response database
21. nginx gunicorn Django S3 ACM Request Response database
22. API gateway Lambda Django S3 ACM Request Response database
23. API gateway Lambda Django S3 ACM Request Response database
24. API gateway Lambda Django S3 ACM Request Response database Lambda Lambda Django Django
25. AWS
26. AWS Certificate Manager bestpuppers.com *.bestpuppers.com Zappa arn:aws:acm:us-east-1:...:certificate/... Still available
27. Simple Storage Service (S3) Zappa S3 bucket best-puppers
28. Lambda WSGI Django WSGI Django WSGI Django
29. API Gateway stage production
30. AWS recap • ACM for SSL certs • S3 for static file storage ◦ (CloudFront for CDN!) • Lambda for request workers • API Gateway for routing
31. Deployment
32. The setup zappa init and zappa_settings.json
33. zappa init $ tree . ├── bestpuppers │ ├── __init__.py │ ├── settings.py │ ├── urls.py │ └── wsgi.py └── manage.py 1 directory, 5 files $ cat ~/.aws/credentials [bestpuppers] aws_access_key_id = ... aws_secret_access_key = ... $ pip install zappa $ zappa init
34. What happens: • Detect application type (Django, Flask, etc.) • Create S3 bucket • Create zappa_settings.json
35. zappa_settings.json { “staging”: { “aws_region”: “us-east-1”, “django_settings”: “bestpuppers.settings”, “profile_name”: “bestpuppers”, “project_name”: “bestpuppers”, “s3_bucket”: “best-puppers”, }, ... }
36. First deployment $ zappa deploy staging Calling deploy for stage staging… Downloading and installing dependencies… Packaging project as zip… Uploading zip (4.3MiB)... Creating API Gateway routes… Deploying API Gateway… Your Zappa deployment is live! https://...execute-api.us-east-1.amazonaws.com/staging
37. What happens: • Freeze Python requirements along with application code into a ZIP file • Upload ZIP file to S3 bucket • Create API Gateway routes • Create Lambda function with code from ZIP file • Hook API Gateway route to Lambda function • Print URL to visit application
38. Updating the application $ zappa update staging Calling update for stage staging… Downloading and installing dependencies… Packaging project as zip… Uploading zip (4.3MiB)... Updating lambda function code... Updating lambda function configuration... Deploying API Gateway... Your updated Zappa deployment is live! https://...execute-api.us-east-1.amazonaws.com/staging
39. Certificates { “staging”: { ..., “certificate_arn”: “arn:aws:acm:us-east-1:...:certificate/...” “domain”: “staging.bestpuppers.com” } } $ zappa certify staging
40. You also get: • Log storage and tailing • Management commands and raw Python in Lambda • Auto-scaling to meet request load (watch out for concurrency and cold start time) • Probably a way lower AWS bill!
41. Odds and ends • Serverless database options ◦ Aurora serverless is a thing; managed solution, but comparable in cost to RDS for now ◦ DynamoDB is a thing; NoSQL solution with no production-ready driver for Django that I know of • Asynchronous tasks ◦ Zappa can run functions on a schedule! ◦ Could split into separate application/Lambda and respond to triggers ◦ Long-running lambdas aren’t well-supported
42. Tips
43. exclude unneeded files! coughnode_modulescough
44. exclude unneeded files • node_modules • .idea/ • media/ • Reduces ZIP file size and upload time
45. Automate your process! Use a task runner like Fabric or npm scripts
46. package.json ..., “scripts”: { “clean”: “rm -rf assets/dist”, “pretest”: “coverage erase”, “test”: “coverage run manage.py test”, “posttest”: “coverage report”, “prebuild”: “npm run clean”, “build”: “webpack”, “build:prod”: “NODE_ENV=production npm run build -- -p --progress”, “prestart”: “npm run clean”, “start”: “webpack --watch”, “predeploy”: “npm run build:prod && npm run test”, “deploy:migrate”: “zappa manage $npm_config_stage migrate”, “deploy:static”: “zappa manage $npm_config_stage ‘collectstatic --noinput’”, “deploy”: “zappa update $npm_config_stage”, “postdeploy”: npm run deploy:migrate && npm run deploy:static” }
47. npm scripts $ npm run deploy --stage=production
48. Thanks! Find me in the hall for a demo
49. Dane Hillard Web Application Developer, ITHAKA Twitter / easyaspython GitHub / daneah