12 Factors of Pain and Suffering

Want to build simple, scalable and reliable web applications? In this presentation, you'll learn all about the 12-Factor App, and the principles it teaches.

You'll also see firsthand how even an experienced programmer has screwed up these best practices in every way imaginable, sometimes with terrible consequences.

Transcript

1. @rdegges
   @rdegges
   12 Factors of
   PAIN and SUFFERING
   Sad Programming Stories
   

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2. @rdegges
   HEY, I'm Randall.
   Head of DevRel @ OKTA
   Python/JS/Go Hacker
   Open Source *
   Author
   Builder
   

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3. @rdegges
   The 12 Factor App
   "A methodology for building simple,
   scalable, and dependable web applications."
   

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4. @rdegges
   I fucked up.
   

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5. @rdegges
   I. Codebase
   One codebase tracked in revision
   control, many deploys.
   Code
   Prod
   Stag
   Dev1
   Dev2
   

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6. @rdegges
   818-217-9229 - Randall Degges
   - Granada Hills, CA 94519
   - He is *not* a spam bot
   - Etc...
   $$$
   I hate your website.
   CODEBASE
   newsketchdomain.com
   CODEBASE1 CODEBASE2
   domain1.com
   domain2.com
   CTRL-C
   +
   CTRL-V
   

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7. @rdegges
   

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8. @rdegges
   II. Dependencies
   Explicitly declare and isolate
   dependencies.
   

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9. @rdegges
   How It Works
   {
   "dependencies": {
   "axios": "^0.18.0",
   "dotenv": "^6.1.0",
   "express": "^4.16.4",
   "vue": "^2.5.17"
   }
   }
   Declare Dependencies
   $ npm install
   + dotenv@6.1.0
   + axios@0.18.0
   + express@4.16.4
   + vue@2.5.17
   added 57 packages from 41 contributors and audited
   128 packages in 2.064s
   found 0 vulnerabilities
   Isolate Dependencies
   

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10. @rdegges
    Image
    Optimization API
    Shrink this image!
    OK! Let me optimize
    that for you.
    VPS
    - optipng
    - jpegoptim
    - gifsicle
    - ...
    code
    optipng
    gifsicle
    

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11. @rdegges
    III. Config
    Store config in the environment
    DATABASE_URL
    MAX_THREADS
    API_KEY
    PRICE
    

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12. @rdegges
    Asterisk
    Fuuuuuuuuuuuuuck.
    Phone calls
    SMS
    Etc.
    Rackspace
    API Key
    Code
    GitHub!
    - $25,000
    

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13. @rdegges
    IV. Backing Services
    Treat backing services as attached
    resources.
    Production
    Deploy
    Postgres
    S3 SMTP
    smtp://auth@host
    https://auth@s3.amazonaws.com
    postgres://auth@host/db
    

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14. @rdegges
    Blog
    MySQL
    I should make a blog.
    I should give out pirated
    movies to everyone.
    ERROR: No disk space
    MySQL
    

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15. @rdegges
    V. Build, Release, Run
    Strictly separate build and run
    stages.
    Code
    Build
    Config
    Release
    

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16. @rdegges
    WEbsite Code
    $ scp -r my_project root@104.102.96.72:
    Web Server
    $ ssh root@104.102.96.72
    (root) $ vim my_project/admin.php
    

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17. @rdegges
    

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18. @rdegges
    VI. Processes
    Execute the app as one or more
    stateless processes.
    

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19. @rdegges
    Conference
    Call App
    Datacenter
    Conference
    Call App
    Conference
    Call App
    818-217-9229
    555-444-3333
    925-431-1337
    

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20. @rdegges
    VII. Port Binding
    Expose services via port binding.
    0.0.0.0:80
    localhost:443
    Routing
    App $PORT
    App $PORT
    App $PORT
    

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21. @rdegges
    VIII. Concurrency
    Scale out via the process model.
    web.1
    web.2
    worker.1
    worker.2
    worker.3
    worker.4
    clock.1
    Process Types
    Scale
    

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22. @rdegges
    IRC Web App
    daemon();
    process
    process
    process
    process
    IRC Room
    IRC Room
    IRC Room
    

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23. @rdegges
    IX. Disposability
    Maximize robustness with fast
    startup and graceful shutdown.
    Shut down gracefully when SIGTTERM is received
    Shut down within a few seconds
    Be robust against sudden death
    

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24. @rdegges
    Process 1
    Load
    Balancer
    Requests
    Process 2
    Process 3
    Process 4
    Process 5
    def startup():
    download_audio()
    listen(env["PORT"])
    

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25. @rdegges
    X. Dev/Prod Parity
    Keep development, staging, and
    production as similar as possible.
    Code
    Postgres
    SQLite
    VARCHARRRRR
    

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26. @rdegges
    XI. Logs
    Treat logs as event streams.
    App
    
    
    
    
    
    
    
    ...
    Order by timestamp
    Write to STDOUT
    Consist of *all* process and backing services logs
    

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27. @rdegges
    Conference
    Call Web App
    Conference
    Call API
    Asterisk
    Asterisk
    Asterisk
    
    
    
    
    
    ...
    calls.csv
    $ scp root@...:calls.csv .
    Log Router
    

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28. @rdegges
    XII. Admin Processes
    Run admin/management tasks
    as one-off processes.
    Code
    Admin
    Task
    Run a database migration
    $ python manage.py migrate
    Prod
    Infrastructure
    

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29. @rdegges
    Run a database migration
    New Feature
    Alter Table DB Migration Code
    "I only need to do this
    once… So..."
    $ python manage.py migrate
    Deploy Feature!
    

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30. @rdegges
    @rdegges
    Thank You
    rdegges.com
    developer.okta.com
    @oktadev
    

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