mikhailshilkov

// Create a Role giving our Lambda access.
let policy: aws.iam.PolicyDocument = { /* Redacted for brevity */ };
let role = new aws.iam.Role("lambda-role", {
    assumeRolePolicy: JSON.stringify(policy),
});
let fullAccess = new aws.iam.RolePolicyAttachment("lambda-access", {
    role: role,
    policyArn: aws.iam.AWSLambdaFullAccess,
});

mikhailshilkov

import * as aws from "@pulumi/aws";

// A DynamoDB table with a single primary key
let counterTable = new aws.dynamodb.Table("urls", {
    name: "urls",
    attributes: [
        { name: "name", type: "S" },
    ],
    hashKey: "name",
    readCapacity: 1,

mikhailshilkov

let workflow wishlist = async {
    let! matches = 
        wishlist.Wishes
        |> List.map findMatchingGift
        |> Async.Parallel

    let gift = pickGift (List.concat matches)
    
    let reservation = { Kid = wishlist.Kid; Product = gift }
    do! reserve reservation

mikhailshilkov

[<FunctionName("FindMatchingGift")>]
let FindMatchingGift([<ActivityTrigger>] wish) = 
    Activity.run findMatchingGiftActivity wish

[<FunctionName("PickGift")>]
let PickGift([<ActivityTrigger>] matches) = 
    Activity.run pickGiftActivity matches

[<FunctionName("Reserve")>]
let Reserve([<ActivityTrigger>] wish) = 

mikhailshilkov

let workflow wishlist = orchestrator {
    let! matches = 
        wishlist.Wishes
        |> List.map (Activity.call findMatchingGiftActivity)
        |> Activity.all

    let! gift = Activity.call pickGiftActivity (List.concat matches)
    
    let reservation = { Kid = wishlist.Kid; Product = gift }
    do! Activity.call reserveActivity reservation

mikhailshilkov

let findMatchingGiftActivity = Activity.defineAsync "FindMatchingGift" findMatchingGift
let pickGiftActivity = Activity.define "PickGift" pickGift
let reserveActivity = Activity.defineAsync "Reserve" reserve

mikhailshilkov

// 1. Simple sequencing of activities
let Run([<OrchestrationTrigger>] context: DurableOrchestrationContext) = task {
  let! hello1 = context.CallActivityAsync<string>("E1_SayHello", "Tokyo")
  let! hello2 = context.CallActivityAsync<string>("E1_SayHello", "Seattle")
  let! hello3 = context.CallActivityAsync<string>("E1_SayHello", "London")
  return [hello1; hello2; hello3]
}     

// 2. Parallel calls snippet
let tasks = Array.map (fun f -> context.CallActivityAsync<int64>("E2_CopyFileToBlob", f)) files

mikhailshilkov

// WishList -> Async<Reservation>
let workflow (wishlist: WishList) = async {

    // 1. Find matches for each wish 
    let! matches = 
        wishlist.Wishes
        |> List.map findMatchingGift
        |> Async.Parallel

    // 2. Pick one product from the combined list of matches

mikhailshilkov

// Reservation -> Async<unit>
let reserve (reservation: Reservation) = async {
    // Call Santa's Archive of Products
}

mikhailshilkov

// Match list -> Product
let pickGift (candidates: Match list) =
    candidates
    |> List.sortByDescending (fun x -> x.Confidence)
    |> List.head
    |> (fun x -> x.Product)