Building resilient and scalable backends using event-driven Serverless

Presented at Bangalore Kubernetes Meetup November 2018 -- running serverless functions on Kubernetes and triggering them on events from the database using Hasura.

Transcript

1. shahidh_k
   Bangalore K8S
   Meetup
   Building Resilient and scalable backends using
   event-driven Serverless
   1
   

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2. shahidh_k 2
   I’m Shahidh
   

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3. shahidh_k
   The Problem
   3
   

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4. shahidh_k
   Traditional architecture
   App
   Database
   API
   Payment microservice Restaurant microservice Delivery microservice
   4
   1. Scalable?
   2. Resilient?
   3. Fun?
   

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5. shahidh_k
   Moving towards scale & resilience
   5
   

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6. shahidh_k
   Async architecture
   App
   Database
   API
   Event system
   Payment processing
   Restaurant approval
   Delivery assignment
   Async microservices
   6
   

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7. shahidh_k
   Serverless
   7
   

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8. shahidh_k
   Serverless
   $ cat index.js
   exports.function = (req, res) => {
   res.json({"message": "Hello World"});
   }
   8
   $ serverless functions deploy hello_world --trigger-http
   https://serverless.functions.net/hello_world
   $ curl https://serverless.functions.net/hello_world
   {"message": "Hello World"}
   

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9. shahidh_k
   Scalable!
   ● No OPS
   ● No VMs to manage
   ● Don’t need to worry about scaling
   ● Just write the code
   ● Deploy
   ● Scale for “free”
   Graphic Source
   9
   

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10. shahidh_k
    Resilient?
    ● Serverless functions are ephemeral
    ● No knowledge of state - async
    ● Trigger them on events
    ● Add retries to the mix
    ● We have resiliency
    10
    

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11. shahidh_k
    Example: Food ordering app
    Column | Value
    -------------------+---------------------------------------
    id | a705a43d-c55b-4a8a-ac16-80679bd02404
    created_at | 2018-09-23 13:24:32.159024+00
    user_id | eca786b6-73ae-44c7-b34f-1757af554464
    is_validated | false
    is_paid | false
    is_approved | false
    is_agent_assigned | false
    11
    

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12. shahidh_k
    Order state machine with serverless
    is_validated | false
    is_paid | false
    is_approved | false
    is_agent_assigned | false
    is_validated | true
    is_paid | false
    is_approved | false
    is_agent_assigned | false
    is_validated | true
    is_paid | true
    is_approved | false
    is_agent_assigned | false
    is_validated | true
    is_paid | true
    is_approved | true
    is_agent_assigned | false
    is_validated | true
    is_paid | true
    is_approved | true
    is_agent_assigned | true
    Checks
    payment
    New order
    Validate
    order
    Restaurant
    approval
    Agent
    assignment
    Completed
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13. shahidh_k
    The cost
    13
    App
    Database
    API
    Event system
    Payment processing
    Restaurant approval
    Delivery assignment
    Generic Event System
    Event system
    Async Serverless Fns
    Payment processing
    Restaurant approval
    Delivery assignment
    

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14. shahidh_k
    High level overview
    Database
    Event system
    Payment
    processing
    Restaurant
    approval
    Delivery
    assignment
    Async serverless
    functions
    A
    Database
    API layer
    Payment
    microservice
    Restaurant
    microservice
    Delivery
    microservice
    Synchronous logic Asynchronous logic
    14
    

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15. shahidh_k
    However, there’s still one
    problem
    

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16. shahidh_k
    GraphQL
    16
    

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17. shahidh_k
    Let’s say I want to build...
    17
    

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18. shahidh_k
    With GraphQL
    ● Standardised spec
    ● All GraphQL Clients are compatible with all
    GraphQL Servers
    ● Client implementations available for all
    major platforms and frameworks
    ● Subscriptions: access to async info
    ● Less work for the developer
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19. shahidh_k
    GraphQL & Serverless architecture
    19
    App
    Database
    Payment processing
    Restaurant approval
    Delivery assignment
    Mutation/Subscriptions Async serverless functions
    

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20. shahidh_k
    Demo Time!
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21. shahidh_k
    Food ordering app
    21
    https://serverless-demo.hasura.app/
    

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22. shahidh_k
    Food ordering app - scalable
    22
    https://serverless-demo.hasura.app/analytics-app
    

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23. shahidh_k
    Food ordering app - resilient
    23
    https://github.com/shahidhk/hasura-serverless
    https://serverless-demo.hasura.app/console
    

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24. shahidh_k 24
    Thanks
    Questions?
    Star us on GitHub
    https://github.com/hasura/graphql-engine
    

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