Stav vlastní orchestrace v Durable Functions (Azure Functions)

Vlastní stav orchestrace umožňuje nastavit vlastní hodnotu stavu pro funkci orchestrátoru. Tento stav se poskytuje prostřednictvím rozhraní HTTP GetStatus API nebo ekvivalentního rozhraní API sady SDK v objektu klienta orchestrace.

Ukázkové případy použití

Vizualizace průběhu

Klienti se můžou dotazovat na koncový bod stavu a zobrazit uživatelské rozhraní průběhu, které vizualizuje aktuální fázi provádění. Následující ukázka ukazuje sdílení průběhu:

C#

Poznámka

Tyto příklady jazyka C# jsou napsané pro Durable Functions 2.x a nejsou kompatibilní s Durable Functions 1.x. Další informace o rozdílech mezi verzemi najdete v článku Durable Functions verze.

[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

E1_HelloSequence funkce orchestrátoru:

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;
});

E1_SayHello funkce aktivity:

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

Python

E1_HelloSequence Orchestrator

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)

E1_SayHello Funkce aktivity

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

PowerShell

E1_HelloSequence Orchestrator

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

E1_SayHello Funkce aktivity

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);
}

A pak klient obdrží výstup orchestrace pouze v případech, kdy CustomStatus je pole nastaveno na "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;
};

Poznámka

V JavaScriptu customStatus se pole nastaví při naplánování další yield akce nebo return akce.

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')

Poznámka

V Pythonu custom_status se pole nastaví při naplánování další yield akce nebo return akce.

PowerShell

Tato funkce není v současné době v PowerShellu implementovaná.

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();
}

Přizpůsobení výstupu

Dalším zajímavým scénářem je segmentace uživatelů vrácením přizpůsobeného výstupu založeného na jedinečných vlastnostech nebo interakcích. Pomocí vlastního stavu orchestrace zůstane kód na straně klienta obecný. Všechny hlavní úpravy budou probíhat na straně serveru, jak je znázorněno v následující ukázce:

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

CityRecommender Orchestrator

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

CityRecommender Orchestrator

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

CityRecommender Orchestrator

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;
}

Specifikace instrukce

Orchestrátor může klientům poskytnout jedinečné pokyny prostřednictvím vlastního stavu. Vlastní stavové pokyny se namapují na kroky v kódu orchestrace:

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;
}

Dotazování vlastního stavu pomocí HTTP

Následující příklad ukazuje, jak se dají dotazovat vlastní hodnoty stavu pomocí integrovaných rozhraní HTTP API.

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;
}

Když je orchestrace spuštěná, externí klienti můžou načíst tento vlastní stav:

GET /runtime/webhooks/durabletask/instances/instance123

Klienti obdrží následující odpověď:

{
  "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"
}

Upozornění

Datová část vlastního stavu je omezená na 16 kB textu JSON UTF-16. Pokud potřebujete větší datovou část, doporučujeme použít externí úložiště.

Další kroky

Informace o trvalých časovačech