État d’orchestration personnalisé dans Fonctions durables (Azure Functions)

L’état d’orchestration personnalisé vous permet de définir une valeur d’état personnalisée pour votre fonction d’orchestrateur. Cet état est fourni via l’API HTTP GetStatus ou l’API ou l’API de SDK équivalente sur l’objet client d’orchestration.

Exemples de cas d’utilisation

Visualiser la progression

Les clients peuvent interroger le point de terminaison de l’état et afficher une interface utilisateur où l’étape d’exécution actuelle est visualisée. L’exemple suivant illustre le partage de la progression :

C#

Notes

Ces exemples C# sont écrits pour Durable Functions 2.x et ne sont pas compatibles avec Durable Functions 1.x. Pour en savoir plus sur les différences entre les versions, consultez l’article Versions de Durable Functions.

[FunctionName("E1_HelloSequence")]
public static async Task<List<string>> Run(
    [OrchestrationTrigger] IDurableOrchestrationContext context)
{
    var outputs = new List<string>();

    outputs.Add(await context.CallActivityAsync<string>("E1_SayHello", "Tokyo"));
    context.SetCustomStatus("Tokyo");
    outputs.Add(await context.CallActivityAsync<string>("E1_SayHello", "Seattle"));
    context.SetCustomStatus("Seattle");
    outputs.Add(await context.CallActivityAsync<string>("E1_SayHello", "London"));
    context.SetCustomStatus("London");

    // returns ["Hello Tokyo!", "Hello Seattle!", "Hello London!"]
    return outputs;
}

[FunctionName("E1_SayHello")]
public static string SayHello([ActivityTrigger] string name)
{
    return $"Hello {name}!";
}

JavaScript

Fonction d’orchestrateur E1_HelloSequence :

const df = require("durable-functions");

module.exports = df.orchestrator(function*(context){
    const outputs = [];

    outputs.push(yield context.df.callActivity("E1_SayHello", "Tokyo"));
    context.df.setCustomStatus("Tokyo");
    outputs.push(yield context.df.callActivity("E1_SayHello", "Seattle"));
    context.df.setCustomStatus("Seattle");
    outputs.push(yield context.df.callActivity("E1_SayHello", "London"));
    context.df.setCustomStatus("London");

    // returns ["Hello Tokyo!", "Hello Seattle!", "Hello London!"]
    return outputs;
});

Fonction d'activité E1_SayHello :

module.exports = async function(context, name) {
    return `Hello ${name}!`;
};

Python

Fonction d’orchestrateur E1_HelloSequence

import azure.functions as func
import azure.durable_functions as df


def orchestrator_function(context: df.DurableOrchestrationContext):
    
    output1 = yield context.call_activity('E1_SayHello', 'Tokyo')
    context.set_custom_status('Tokyo')
    output2 = yield context.call_activity('E1_SayHello', 'Seattle')
    context.set_custom_status('Seattle')
    output3 = yield context.call_activity('E1_SayHello', 'London')
    context.set_custom_status('London')
    
    return [output1, output2, output3]

main = df.Orchestrator.create(orchestrator_function)

Fonction d’activité E1_SayHello

def main(name: str) -> str:
    return f"Hello {name}!"

PowerShell

Fonction d’orchestrateur E1_HelloSequence

param($Context)

$output = @()

$output += Invoke-DurableActivity -FunctionName 'E1_SayHello' -Input 'Tokyo'
Set-DurableCustomStatus -CustomStatus 'Tokyo'

$output += Invoke-DurableActivity -FunctionName 'E1_SayHello' -Input 'Seattle'
Set-DurableCustomStatus -CustomStatus 'Seattle'

$output += Invoke-DurableActivity -FunctionName 'E1_SayHello' -Input 'London'
Set-DurableCustomStatus -CustomStatus 'London'


return $output

Fonction d’activité E1_SayHello

param($name)

"Hello $name"

Java

@FunctionName("HelloCities")
public String helloCitiesOrchestrator(
        @DurableOrchestrationTrigger(name = "ctx") TaskOrchestrationContext ctx) {
    String result = "";
    result += ctx.callActivity("SayHello", "Tokyo", String.class).await() + ", ";
    ctx.setCustomStatus("Tokyo");
    result += ctx.callActivity("SayHello", "London", String.class).await() + ", ";
    ctx.setCustomStatus("London");
    result += ctx.callActivity("SayHello", "Seattle", String.class).await();
    ctx.setCustomStatus("Seattle");
    return result;
}

@FunctionName("SayHello")
public String sayHello(@DurableActivityTrigger(name = "name") String name) {
    return String.format("Hello %s!", name);
}

Le client reçoit ensuite la sortie de l’orchestration uniquement quand le champ CustomStatus est défini sur « London » :

C#

[FunctionName("HttpStart")]
public static async Task<HttpResponseMessage> Run(
    [HttpTrigger(AuthorizationLevel.Function, methods: "post", Route = "orchestrators/{functionName}")] HttpRequestMessage req,
    [DurableClient] IDurableOrchestrationClient starter,
    string functionName,
    ILogger log)
{
    // Function input comes from the request content.
    dynamic eventData = await req.Content.ReadAsAsync<object>();
    string instanceId = await starter.StartNewAsync(functionName, (string)eventData);

    log.LogInformation($"Started orchestration with ID = '{instanceId}'.");

    DurableOrchestrationStatus durableOrchestrationStatus = await starter.GetStatusAsync(instanceId);
    while (durableOrchestrationStatus.CustomStatus.ToString() != "London")
    {
        await Task.Delay(200);
        durableOrchestrationStatus = await starter.GetStatusAsync(instanceId);
    }

    HttpResponseMessage httpResponseMessage = new HttpResponseMessage(HttpStatusCode.OK)
    {
        Content = new StringContent(JsonConvert.SerializeObject(durableOrchestrationStatus))
    };

    return httpResponseMessage;
  }
}

JavaScript

const df = require("durable-functions");

module.exports = async function(context, req) {
    const client = df.getClient(context);

    // Function input comes from the request content.
    const eventData = req.body;
    const instanceId = await client.startNew(req.params.functionName, undefined, eventData);

    context.log(`Started orchestration with ID = '${instanceId}'.`);

    let durableOrchestrationStatus = await client.getStatus(instanceId);
    while (durableOrchestrationStatus.customStatus.toString() !== "London") {
        await new Promise((resolve) => setTimeout(resolve, 200));
        durableOrchestrationStatus = await client.getStatus(instanceId);
    }

    const httpResponseMessage = {
        status: 200,
        body: JSON.stringify(durableOrchestrationStatus),
    };

    return httpResponseMessage;
};

Notes

Dans JavaScript, le champ customStatus sera défini lorsque la prochaine action yield ou return est planifiée.

Python

import json
import logging
import azure.functions as func
import azure.durable_functions as df
from time import sleep

async def main(req: func.HttpRequest, starter: str) -> func.HttpResponse:
    client = df.DurableOrchestrationClient(starter)    
    instance_id = await client.start_new(req.params.functionName, None, None)

    logging.info(f"Started orchestration with ID = '{instance_id}'.")

    durable_orchestration_status = await client.get_status(instance_id)
    while durable_orchestration_status.custom_status != 'London':
        sleep(0.2)
        durable_orchestration_status = await client.get_status(instance_id)

    return func.HttpResponse(body='Success', status_code=200, mimetype='application/json')

Notes

Dans Python, le champ custom_status sera défini lors de la planification de la prochaine action yield ou return.

PowerShell

La fonctionnalité n’est pas implémentée actuellement dans PowerShell

Java

@FunctionName("StartHelloCities")
public HttpResponseMessage startHelloCities(
        @HttpTrigger(name = "req") HttpRequestMessage<Void> req,
        @DurableClientInput(name = "durableContext") DurableClientContext durableContext,
        final ExecutionContext context) throws InterruptedException {

    DurableTaskClient client = durableContext.getClient();
    String instanceId = client.scheduleNewOrchestrationInstance("HelloCities");
    context.getLogger().info("Created new Java orchestration with instance ID = " + instanceId);

    OrchestrationMetadata metadata;
    try {
        metadata = client.waitForInstanceStart(instanceId, Duration.ofMinutes(5), true);
    } catch (TimeoutException ex) {
        return req.createResponseBuilder(HttpStatus.INTERNAL_SERVER_ERROR).build();
    }

    while (metadata.readCustomStatusAs(String.class) != "London") {
        Thread.sleep(200);
        metadata = client.getInstanceMetadata(instanceId, true);
    }

    return req.createResponseBuilder(HttpStatus.OK).build();
}

Personnalisation de la sortie

Un autre scénario intéressant consiste à segmenter les utilisateurs en renvoyant une sortie personnalisée basée sur des caractéristiques ou des interactions uniques. Grâce à l’état d’orchestration personnalisé, le code côté client reste générique. Toutes les modifications principales se produisent côté serveur, comme l’illustre l’exemple suivant :

C#

[FunctionName("CityRecommender")]
public static void Run(
  [OrchestrationTrigger] IDurableOrchestrationContext context)
{
  int userChoice = context.GetInput<int>();

  switch (userChoice)
  {
    case 1:
    context.SetCustomStatus(new
    {
      recommendedCities = new[] {"Tokyo", "Seattle"},
      recommendedSeasons = new[] {"Spring", "Summer"}
     });
      break;
    case 2:
      context.SetCustomStatus(new
      {
        recommendedCities = new[] {"Seattle, London"},
        recommendedSeasons = new[] {"Summer"}
      });
        break;
      case 3:
      context.SetCustomStatus(new
      {
        recommendedCities = new[] {"Tokyo, London"},
        recommendedSeasons = new[] {"Spring", "Summer"}
      });
        break;
  }

  // Wait for user selection and refine the recommendation
}

JavaScript

Orchestrateur CityRecommender

const df = require("durable-functions");

module.exports = df.orchestrator(function*(context) {
    const userChoice = context.df.getInput();

    switch (userChoice) {
        case 1:
            context.df.setCustomStatus({
                recommendedCities: [ "Tokyo", "Seattle" ],
                recommendedSeasons: [ "Spring", "Summer" ],
            });
            break;
        case 2:
            context.df.setCustomStatus({
                recommendedCities: [ "Seattle", "London" ],
                recommendedSeasons: [ "Summer" ],
            });
            break;
        case 3:
            context.df.setCustomStatus({
                recommendedCity: [ "Tokyo", "London" ],
                recommendedSeasons: [ "Spring", "Summer" ],
            });
            break;
    }

    // Wait for user selection and refine the recommendation
});

Python

Orchestrateur CityRecommender

import azure.functions as func
import azure.durable_functions as df

def orchestrator_function(context: df.DurableOrchestrationContext):
    userChoice = int(context.get_input())

    if userChoice == 1:
        context.set_custom_status({
            'recommendedCities' : ['Tokyo', 'Seattle'], 
            'recommendedSeasons' : ['Spring', 'Summer']
        }))
    if userChoice == 2:
        context.set_custom_status({
            'recommendedCities' : ['Seattle', 'London']
            'recommendedSeasons' : ['Summer']
        }))
    if userChoice == 3:
        context.set_custom_status({
            'recommendedCities' : ['Tokyo', 'London'], 
            'recommendedSeasons' : ['Spring', 'Summer']
        }))



    # Wait for user selection and refine the recommendation

main = df.Orchestrator.create(orchestrator_function)

PowerShell

Orchestrateur CityRecommender

param($Context)

$userChoice = $Context.Input -as [int]

if ($userChoice -eq 1) {
    Set-DurableCustomStatus -CustomStatus @{ recommendedCities = @('Tokyo', 'Seattle'); 
                                             recommendedSeasons = @('Spring', 'Summer') 
                                            }  
}

if ($userChoice -eq 2) {
    Set-DurableCustomStatus -CustomStatus @{ recommendedCities = @('Seattle', 'London'); 
                                             recommendedSeasons = @('Summer') 
                                            }  
}

if ($userChoice -eq 3) {
    Set-DurableCustomStatus -CustomStatus @{ recommendedCities = @('Tokyo', 'London'); 
                                             recommendedSeasons = @('Spring', 'Summer') 
                                            }  
}

# Wait for user selection and refine the recommendation

Java

@FunctionName("CityRecommender")
public void cityRecommender(
        @DurableOrchestrationTrigger(name = "ctx") TaskOrchestrationContext ctx) {
    int userChoice = ctx.getInput(int.class);
    switch (userChoice) {
        case 1:
            ctx.setCustomStatus(new Recommendation(
                    new String[]{ "Tokyo", "Seattle" },
                    new String[]{ "Spring", "Summer" }));
            break;
        case 2:
            ctx.setCustomStatus(new Recommendation(
                    new String[]{ "Seattle", "London" },
                    new String[]{ "Summer" }));
            break;
        case 3:
            ctx.setCustomStatus(new Recommendation(
                    new String[]{ "Tokyo", "London" },
                    new String[]{ "Spring", "Summer" }));
            break;
    }

    // Wait for user selection with an external event
}

class Recommendation {
    public Recommendation() { }

    public Recommendation(String[] cities, String[] seasons) {
        this.recommendedCities = cities;
        this.recommendedSeasons = seasons;
    }

    public String[] recommendedCities;
    public String[] recommendedSeasons;
}

Spécification d’instructions

L’orchestrateur peut fournir des instructions uniques aux clients via l’état personnalisé. Les instructions de l’état personnalisé sont mappées avec les étapes du code de l’orchestration :

C#

[FunctionName("ReserveTicket")]
public static async Task<bool> Run(
  [OrchestrationTrigger] IDurableOrchestrationContext context)
{
  string userId = context.GetInput<string>();

  int discount = await context.CallActivityAsync<int>("CalculateDiscount", userId);

  context.SetCustomStatus(new
  {
    discount = discount,
    discountTimeout = 60,
    bookingUrl = "https://www.myawesomebookingweb.com",
  });

  bool isBookingConfirmed = await context.WaitForExternalEvent<bool>("BookingConfirmed");

  context.SetCustomStatus(isBookingConfirmed
    ? new {message = "Thank you for confirming your booking."}
    : new {message = "The booking was not confirmed on time. Please try again."});

  return isBookingConfirmed;
}

JavaScript

const df = require("durable-functions");

module.exports = df.orchestrator(function*(context) {
    const userId = context.df.getInput();

    const discount = yield context.df.callActivity("CalculateDiscount", userId);

    context.df.setCustomStatus({
        discount,
        discountTimeout = 60,
        bookingUrl = "https://www.myawesomebookingweb.com",
    });

    const isBookingConfirmed = yield context.df.waitForExternalEvent("bookingConfirmed");

    context.df.setCustomStatus(isBookingConfirmed
        ? { message: "Thank you for confirming your booking." }
        : { message: "The booking was not confirmed on time. Please try again." }
    );

    return isBookingConfirmed;
});

Python

import azure.functions as func
import azure.durable_functions as df

def orchestrator_function(context: df.DurableOrchestrationContext):
    userId = int(context.get_input())

    discount = yield context.call_activity('CalculateDiscount', userId)

    status = { 'discount' : discount,
        'discountTimeout' : 60,
        'bookingUrl' : "https://www.myawesomebookingweb.com",
    }
    context.set_custom_status(status)

    is_booking_confirmed = yield context.wait_for_external_event('BookingConfirmed')
    context.set_custom_status({'message': 'Thank you for confirming your booking.'} if is_booking_confirmed 
        else {'message': 'The booking was not confirmed on time. Please try again.'})
    return is_booking_confirmed

main = df.Orchestrator.create(orchestrator_function)

PowerShell

param($Context)

$userId = $Context.Input -as [int]

$discount = Invoke-DurableActivity -FunctionName 'CalculateDiscount' -Input $userId

$status = @{
            discount = $discount;
            discountTimeout = 60;
            bookingUrl = "https://www.myawesomebookingweb.com"
            }

Set-DurableCustomStatus -CustomStatus $status

$isBookingConfirmed = Invoke-DurableActivity -FunctionName 'BookingConfirmed'

if ($isBookingConfirmed) {
    Set-DurableCustomStatus -CustomStatus @{message = 'Thank you for confirming your booking.'}
} else {
    Set-DurableCustomStatus -CustomStatus @{message = 'The booking was not confirmed on time. Please try again.'}
}

return $isBookingConfirmed

Java

@FunctionName("ReserveTicket")
public boolean reserveTicket(
        @DurableOrchestrationTrigger(name = "ctx") TaskOrchestrationContext ctx) {
    String userID = ctx.getInput(String.class);
    int discount = ctx.callActivity("CalculateDiscount", userID, int.class).await();
    ctx.setCustomStatus(new DiscountInfo(discount, 60, "https://www.myawesomebookingweb.com"));

    boolean isConfirmed = ctx.waitForExternalEvent("BookingConfirmed", boolean.class).await();
    if (isConfirmed) {
        ctx.setCustomStatus("Thank you for confirming your booking.");
    } else {
        ctx.setCustomStatus("There was a problem confirming your booking. Please try again.");
    }

    return isConfirmed;
}

class DiscountInfo {
    public DiscountInfo() { }
    public DiscountInfo(int discount, int discountTimeout, String bookingUrl) {
        this.discount = discount;
        this.discountTimeout = discountTimeout;
        this.bookingUrl = bookingUrl;
    }
    public int discount;
    public int discountTimeout;
    public String bookingUrl;
}

Interrogation d’un état personnalisé avec HTTP

L’exemple suivant montre comment les valeurs d’état personnalisées peuvent être interrogées à l’aide des API HTTP intégrées.

C#

public static async Task SetStatusTest([OrchestrationTrigger] IDurableOrchestrationContext context)
{
    // ...do work...

    // update the status of the orchestration with some arbitrary data
    var customStatus = new { nextActions = new [] {"A", "B", "C"}, foo = 2, };
    context.SetCustomStatus(customStatus);

    // ...do more work...
}

JavaScript

const df = require("durable-functions");

module.exports = df.orchestrator(function*(context) {
    // ...do work...

    // update the status of the orchestration with some arbitrary data
    const customStatus = { nextActions: [ "A", "B", "C" ], foo: 2, };
    context.df.setCustomStatus(customStatus);

    // ...do more work...
});

Python

import azure.functions as func
import azure.durable_functions as df

def orchestrator_function(context: df.DurableOrchestrationContext):
    # ...do work...

    custom_status = {'nextActions': ['A','B','C'], 'foo':2}
    context.set_custom_status(custom_status)

    # ...do more work...

main = df.Orchestrator.create(orchestrator_function)

PowerShell

param($Context)

# ...do work...

Set-DurableCustomStatus -CustomStatus @{ nextActions = @('A', 'B', 'C'); 
                                         foo = 2 
                                        }  

# ...do more work...

Java

@FunctionName("MyCustomStatusOrchestrator")
public void myCustomStatusOrchestrator(
        @DurableOrchestrationTrigger(name = "ctx") TaskOrchestrationContext ctx) {
    // ... do work ...

    // update the status of the orchestration with some arbitrary data
    CustomStatusPayload payload = new CustomStatusPayload();
    payload.nextActions = new String[] { "A", "B", "C" };
    payload.foo = 2;
    ctx.setCustomStatus(payload);

    // ... do more work ...
}

class CustomStatusPayload {
    public String[] nextActions;
    public int foo;
}

Pendant l’exécution de l’orchestration, les clients externes peuvent récupérer cet état personnalisé :

GET /runtime/webhooks/durabletask/instances/instance123

Les clients obtiennent la réponse suivante :

{
  "runtimeStatus": "Running",
  "input": null,
  "customStatus": { "nextActions": ["A", "B", "C"], "foo": 2 },
  "output": null,
  "createdTime": "2019-10-06T18:30:24Z",
  "lastUpdatedTime": "2019-10-06T19:40:30Z"
}

Avertissement

La charge utile d’état personnalisé est limitée à 16 ko de texte JSON UTF-16. Nous vous recommandons d’utiliser un stockage externe si vous avez besoin d’une charge utile plus importante.

Étapes suivantes

En savoir plus sur les minuteurs durables