Serverless for Developers: Tips for Your Next App

Serverless Meetup, Milan, November 3rd, 2016

Serverless architectures simplify operations and maintenance of production applications, abstracting from the underlining infrastructure and OS. But what about development? We are now two years in with tools such as AWS Lambda and what are the best practices to share from a development perspective? In this session you will see some of the key points that can empower a serverless developer: from event-driven design, to simplification (less is more, especially for a small team), extending the functionalities of the platform (per prefix stats for S3 buckets, geohash for DynamoDB tables, API authentication, and so on), integrating new products.

Transcript

1. Serverless for Developers:
   Tips for Your Next App
   Danilo Poccia, Technical Evangelist
   @danilop
   danilop
   

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3. Credit: Gerry Cranham/Fox Photos/Getty Images
   http://www.telegraph.co.uk/travel/destinations/europe/united-kingdom/england/london/galleries/The-history-of-the-Tube-in-pictures-150-years-of-London-Underground/1939-ticket-examin/
   

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4. Credit: Gerry Cranham/Fox Photos/Getty Images
   http://www.telegraph.co.uk/travel/destinations/europe/united-kingdom/england/london/galleries/The-history-of-the-Tube-in-pictures-150-years-of-London-Underground/1939-ticket-examin/
   1939 London Underground
   

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5. AWS
   IoT
   Kinesis
   Stream
   AWS
   Lambda
   DynamoDB
   Table
   S3
   Bucket
   

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6. Virtual Machines Containers Functions
   

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7. Code Microseconds
   to Seconds
   Versioning Single-Threaded
   Single-Task
   Per Memory/Second
   Per Request
   Free Tier
   The World of Lambda Functions
   

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8. No server is easier to
   manage than no server
   Serverless Computing
   

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9. Low Cost
   Security
   Simplicity Reliability
   Scalability Low Latency
   S3: Simple By Name, Simple By Nature
   

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10. Mobile Apps
    Websites
    Services
    Internet
    API Gateway Cache
    API Gateway
    CloudWatch
    Lambda Functions
    EC2 Endpoints
    Any Other Endpoint
    Amazon API Gateway
    

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11. Building An Infinitely Scalable Online Recording Campaign
    For David Guetta & UEFA
    

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12. Dev + Ops
    

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13. Dev + Ops
    + Event Driven
    

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14. Name
    Email
    Create New User
    Submit
    Check the “Name” syntax is right
    (only letters and spaces)
    Check the “Email” syntax is right
    (something@some.domain)
    Create the new user using
    provided Name and Email
    User Interface Actions
    

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15. Name
    Email
    Create New User
    Submit
    Check the “Name” syntax is right
    (only letters and spaces)
    Check the “Email” syntax is right
    (something@some.domain)
    Create the new user using
    provided Name and Email
    User Interface Actions
    Observers
    Target Action
    

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16. Generate thumbnails
    Keep another database in sync
    Process streaming data
    Services Functions
    Platform
    Target Action
    Kinesis
    Stream
    DynamoDB
    Table
    S3
    Bucket
    

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17. area = length x width
    

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18. area = length x width
    Procedural Programming
    “This is a function!”
    

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19. area = length x width
    Procedural Programming
    “This is a function!”
    Reactive Programming
    “This is data binding!”
    

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20. A B
    Event-Driven Design
    For Services
    A triggers B
    or better
    B is caused by A
    

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21. A B
    C
    D
    New Services C and D
    are triggered caused by B
    

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22. A B
    C
    D
    E
    F
    ?
    ?
    What is causing E and F?
    

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23. A B
    C
    D
    E
    F
    New Services (E, F)
    are triggered by C
    

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24. A B
    C
    D
    E
    F
    It can be cyclic
    Think of
    acknowledgements
    

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25. A B
    C
    D
    E
    F
    Each service
    has local visibility
    

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26. A B
    C
    D
    E
    F
    What I need to know
    (input events)
    1
    

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27. A B
    C
    D
    E
    F
    What I need to do
    (internal logic)
    2
    

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28. A B
    C
    D
    E
    F
    Who I need to notify
    (output events)
    3
    

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29. A B
    C
    D
    E
    F
    Who I need to notify
    (output events)
    What I need to know
    (input events)
    What I need to do
    (internal logic)
    1
    2
    3
    

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30. Distributed Data Flow
    Vs
    Centralised Workflow
    

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31. Choreography
    Vs
    Orchestration
    

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32. Distributed Systems
    

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33. Monolith
    Service
    Service
    μ
    μ
    μ
    space (distribution, mobility)
    time (concurrency, latency)
    μ
    μ
    μ
    μ
    “Distributed
    in Time and Space”
    [Jonas Bonér]
    

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34. “…a diagram of
    two microservices
    and their shared database”
    Data should drive
    the boundaries
    

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35. A
    C
    I
    D
    tomic
    onsistent
    isolated
    urable
    

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36. A
    C
    I
    D
    tomic
    onsistent
    isolated
    urable
    A
    C
    I
    D
    ssociative
    ommutative
    dempotent
    istributed
    ACID 2.0
    

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37. A B
    C
    D
    E
    F
    Event-Driven Interactions replacing Distributed Transactions
    using Eventual Consistency
    

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38. A B
    C
    D
    E
    F
    Event-Driven Interactions replacing Distributed Transactions
    using Eventual Consistency
    Differentiate reads (queries)
    from writes (commands),
    as in the Command Query
    Responsibility Segregation
    (CQRS) pattern
    command query
    

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39. Customers Orders
    Warehouse Deliveries
    Payments
    Catalog
    Event-Driven Interactions replacing Distributed Transactions
    using Eventual Consistency
    

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40. Scale
    from Prototype to Production
    

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41. Responsive
    Resilient
    Elastic
    Message Driven
    The Reactive Manifesto
    

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42. The Reactive Manifesto
    Asynchronous
    communication
    is not enforced
    by serverless architectures
    Responsive
    Resilient
    Elastic
    Message Driven
    

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43. Serverless Architectural Patterns
    

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44. AWS
    Lambda
    User Client
    Application
    Back End for a Web or Mobile App
    Calling the Lambda API directly
    Web or Mobile Back End
    DynamoDB
    Table
    S3
    Bucket
    Amazon
    Cognito
    AWS API
    

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45. AWS
    Lambda
    Amazon
    Cognito
    User
    Client
    Application
    OAuth JWT
    Amazon
    API Gateway
    Back End for a Web or Mobile App
    Using an API Gateway for authentication and decoupling
    Web or Mobile Back End
    Via API Gateway
    DynamoDB
    Table
    S3
    Bucket
    HTTPS
    

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46. Using WebSockets instead of Web API to talk to the Back End
    WebSockets Back End
    AWS
    Lambda
    User
    Client
    Application
    AWS
    IoT
    DynamoDB
    Table
    S3
    Bucket
    Amazon
    Cognito
    MQTT or
    Device
    Shadow
    MQTT over

    WebSockets
    

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47. Server ! Client
    {
    "id": "...",
    "html": "..."
    }
    {
    "js": "..."
    }
    Client ! Server
    {
    "cmd": "...",
    "data": "..."
    }
    MQTT Topics
    myapp/client/in/{ID}
    myapp/client/out/{ID}
    Cognito Identity ID ! {ID}
    1
    2
    3
    4
    AWS
    Lambda
    User
    Client
    Application
    AWS
    IoT
    DynamoDB
    Table
    S3
    Bucket
    Amazon
    Cognito
    MQTT or
    Device
    Shadow
    MQTT over

    WebSockets
    

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48. Possible optimisations depending on your data flow
    and your acceptable latency
    Data
    Source
    Kinesis
    Stream
    Kinesis
    Firehose
    Kinesis
    Analytics
    (augment
    & aggregate)
    AWS
    Lambda
    (batch)
    S3
    Bucket
    AWS
    Lambda
    (file)
    Data Streams
    Processing
    Reference
    Data
    

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49. AWS
    Lambda
    (batch)
    Amazon
    Cognito
    User
    Client
    Application
    Buffering Requests to the Back End to reduce Lambda invocations
    Kinesis
    Stream
    Buffered
    Back End For Mobile
    Amazon
    SNS
    DynamoDB
    Table
    S3
    Bucket
    

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50. AWS
    Lambda
    (batch)
    Amazon
    Cognito
    User
    Client
    Application
    Buffering Requests to the Back End to reduce Lambda invocations
    Kinesis
    Stream
    Buffered & Aggregated

    Back End For Mobile
    Amazon
    SNS
    DynamoDB
    Table
    S3
    Bucket
    Kinesis
    Analytics
    (aggregate)
    Kinesis
    Stream
    

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51. AWS
    Lambda
    (batch)
    User
    Client
    Application
    Using WebSockets instead of Web API to talk to the Back End
    Buffering Requests to reduce Lambda invocations
    AWS
    IoT
    Kinesis
    Stream
    Buffered Back End
    For Everything
    MQTT or
    Device Shadow
    Amazon
    Cognito
    DynamoDB
    Table
    S3
    Bucket
    

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52. User
    Client
    Application
    Using WebSockets instead of Web API to talk to the Back End
    Buffering Requests to reduce Lambda invocations
    Storing all customer interactions for further analysis
    AWS
    IoT
    Kinesis
    Firehose
    Buffered Back End
    Saving Interactions
    MQTT or
    Device Shadow
    Amazon
    Cognito
    AWS
    Lambda
    (file)
    S3
    Bucket
    DynamoDB
    Table
    

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53. AWS
    Lambda
    DynamoDB
    Table
    User
    Client
    Application
    Amazon
    API Gateway
    (HTTPS)
    S3 Bucket
    (Website Hosting
    Routing Rules)
    For example, to generate image thumbnails on the first request,
    S3 LifeCycle Rules can delete content after N days
    Dynamic Cache
    Amazon
    Cognito
    HTTP
    Redirect
    Dynamically
    Build Content
    

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54. Content Delivery
    Amazon
    API Gateway
    CloudFront
    Distribution
    S3 Bucket
    AWS
    Lambda
    DynamoDB
    Table
    S3
    Bucket
    Single DNS domain for both static and dynamic content, protected by the WAF,

    DNS health checks can react automatically to service downtime
    User
    Client
    Application
    Amazon
    Route 53
    DNS
    Resolution
    Health
    Checks
    AWS
    WAF
    

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55. Data Analytics
    S3
    Bucket
    Redshift
    Database
    DynamoDB
    Table #N
    AWS
    Lambda
    Kinesis
    Firehose
    Synchronize operational NoSQL databases

    with a columnar store for business intelligence and analytics
    Business
    Intelligence
    DynamoDB
    Table #1
    AWS
    Lambda
    Kinesis
    Firehose
    .
    .
    .
    .
    .
    .
    .
    .
    .
    

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56. To receive events from everywhere on the Internet
    Webhooks are callbacks for the Web
    AWS
    Lambda
    Amazon
    API Gateway
    Internet
    Service
    HTTP(S) GET or POST to https://domain/SOURCE/RANDOM-HOOK
    Webhook
    Other AWS
    Services
    Other public
    APIs
    AWS
    KMS
    Secrets &
    Credentials
    

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57. To generate events
    for repositories
    that don’t support
    AWS Lambda natively
    Log
    Monitor
    AWS
    Lambda
    AWS
    Lambda
    AWS
    Lambda
    Amazon
    SNS
    Kinesis
    Stream
    Log
    Files
    External
    Application
    Log Monitor
    CloudWatch
    Logs or Metrics
    AWS
    Lambda
    

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58. S3 object auto compress
    S3 bucket per prefix statistics
    DynamoDB provisioned throughput dynamic scaling
    DynamoDB item support for geohash
    Relational / NoSQL data synchronisation
    MapReduce with Lambda functions on S3 buckets
    Service discovery
    . . .
    Extending Services with Your Own Functionalities
    

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59. Serverless === Architecture Simplification
    

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60. Serverless === Architecture Simplification
    For example, let’s build a Media Sharing App
    

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61. Client
    Application
    Get Content
    Index
    Get Content
    and Thumbnails
    Upload Content
    with Metadata
    Update Content
    Metadata
    Get Content
    Metadata
    Files
    (Multimedia)
    Database
    Build
    Thumbnails
    Update
    Content Index
    Extract
    and Update
    Metadata
    Functions
    User
    Resources
    Basic
    features
    M
    edia
    Sharing
    App
    

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62. Client
    Application
    Get Content
    Index
    Get Content
    and Thumbnails
    Upload Content
    with Metadata
    Update Content
    Metadata
    Get Content
    Metadata
    Files
    (Multimedia)
    Database
    Build
    Thumbnails
    Update
    Content Index
    Extract
    and Update
    Metadata
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    Functions
    User
    Resources
    Event-driven
    design
    M
    edia
    Sharing
    App
    

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63. Client
    Application
    Get Content
    Index
    Get Content
    and Thumbnails
    Upload Content
    with Metadata
    Update Content
    Metadata
    Get Content
    Metadata
    Files
    (Multimedia)
    Database
    Build
    Thumbnails
    Update
    Content Index
    Extract
    and Update
    Metadata
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    Functions
    User
    Resources
    Understanding
    the overall flow
    M
    edia
    Sharing
    App
    

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64. Client
    Application Get Content Index
    (S3 API)
    Get Content
    and Thumbnails
    (S3 API)
    Upload Content

    with Metadata
    (S3 API)
    Update Content
    Metadata
    (DynamoDB API)
    Get Content Metadata
    (DynamoDB API)
    S3
    Bucket
    DynamoDB
    Table
    Build Thumbnails
    (Lambda function)
    Update
    Content Index
    (Lambda function)
    Extract and Update
    Metadata
    (Lambda function)
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    User
    Choosing
    the technology
    M
    edia
    Sharing
    App
    

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65. Client
    Application Get Content Index
    (S3 API)
    Get Content
    and Thumbnails
    (S3 API)
    Upload Content

    with Metadata
    (S3 API)
    Update Content
    Metadata
    (DynamoDB API)
    Get Content Metadata

    (DynamoDB API)
    S3
    Bucket
    DynamoDB
    Table
    Build Thumbnails
    (Lambda function)
    Update
    Content Index
    (Lambda function)
    Extract and Update
    Metadata
    (Lambda function)
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    User
    Amazon
    Cognito
    Defining
    the security model
    M
    edia
    Sharing
    App
    

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66. Client
    Application Get Content Index
    (S3 API)
    Get Content
    and Thumbnails
    (S3 API)
    Upload Content

    with Metadata
    (S3 API)
    Update Content
    Metadata
    (DynamoDB API)
    Get Content Metadata

    (DynamoDB API)
    S3
    Bucket
    DynamoDB
    Table
    Build Thumbnails
    (Lambda function)
    Update
    Content Index
    (Lambda function)
    Extract and Update
    Metadata
    (Lambda function)
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    User
    Amazon
    Cognito
    From the features
    viewpoint…
    M
    edia
    Sharing
    App
    

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67. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    buildThumbnails
    (Lambda function)
    updateContentIndex
    (Lambda function)
    extractAndUpdateMetadata
    (Lambda function)
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    User
    Amazon
    Cognito
    Amazon S3
    Amazon DynamoDB
    AWS Lambda
    …To the technology
    viewpoint
    M
    edia
    Sharing
    App
    

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68. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    buildThumbnails
    (Lambda function)
    updateContentIndex
    (Lambda function)
    extractAndUpdateMetadata
    (Lambda function)
    Event:
    new or
    updated
    file
    Event:
    new or updated
    content metadata
    User
    Amazon
    Cognito
    Amazon S3
    Amazon DynamoDB
    AWS Lambda
    Some events
    are correlated
    M
    edia
    Sharing
    App
    

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69. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    contentUpdated
    (Lambda function)
    buildThumbnails
    extractAndUpdateMetadata
    updateContentIndex
    (Lambda function)
    Event:
    new or
    updated
    file
    User
    Amazon
    Cognito
    Amazon S3 AWS Lambda
    Amazon DynamoDB
    Event:
    new or updated
    content metadata
    Some functions
    can be tied together
    M
    edia
    Sharing
    App
    

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70. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    contentUpdated
    (Lambda function)
    buildThumbnails
    extractAndUpdateMetadata
    updateContentIndex
    (Lambda function)
    Event:
    new or
    updated
    file
    User
    Amazon
    Cognito
    Amazon S3 AWS Lambda
    Amazon DynamoDB
    Event:
    new or updated
    content metadata
    What if I want to
    delete content?
    M
    edia
    Sharing
    App
    

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71. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    contentUpdated
    (Lambda function)
    buildThumbnails
    extractAndUpdateMetadata
    deleteMetadata
    updateContentIndex
    (Lambda function)
    Event:
    new, updated,
    or deleted
    file
    User
    Amazon
    Cognito
    Amazon S3 AWS Lambda
    Amazon DynamoDB
    DELETE Object
    S3 API
    Event:
    new or updated
    content metadata
    REST to the rescue,
    the events flow is
    almost unchanged
    M
    edia
    Sharing
    App
    

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72. Client
    Application
    GET Object
    S3 API
    PUT Object
    S3 API
    UpdateItem
    DynamoDB API
    GetItem

    DynamoDB API
    S3
    Bucket
    DynamoDB
    Table
    contentUpdated
    (Lambda function)
    buildThumbnails
    extractAndUpdateMetadata
    deleteMetadata
    updateContentIndex
    (Lambda function)
    Event:
    new, updated,
    or deleted
    file
    User
    Amazon
    Cognito
    Amazon S3 AWS Lambda
    Amazon DynamoDB
    DELETE Object
    S3 API
    Event:
    new or updated
    content metadata
    From 8 functions to 2,
    using 5 native
    API calls
    M
    edia
    Sharing
    App
    

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73. Serverless Architectures are not just simplifying Operations
    

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74. Developers can benefit from:
    event-driven design
    architectural patterns
    integrating new products
    architecture simplification
    customization of the platform
    Serverless Architectures are not just simplifying Operations
    

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75. Build Apps With Services,
    Not Servers
    

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76. Thank you
    @danilop
    danilop
    

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