Wait for sidecar readyness before starting apps up.

Closes #182

Signed-off-by: Tiago Alves Macambira <[email protected]>

feed-generator/Program.cs

@@ -14,6 +14,7 @@ namespace FeedGenerator
     using Microsoft.Extensions.Logging;
     using Prometheus;
     using System;
+    using System.Threading;
     using System.Threading.Tasks;
 
     /// <summary>
@@ -80,6 +81,14 @@ static internal async void StartMessageGeneratorAsync(int delayInMilliseconds, I
             DaprClientBuilder daprClientBuilder = new DaprClientBuilder();
 
             DaprClient client = daprClientBuilder.Build();
+
+            // When ran in k8s, this app might start before Dapr sidecar is ready
+            // and this will lead to errors. Let's wait a bit for the sidecar to
+            // be ready before we start publishing.
+            logger.LogInformation("Waiting for Dapr sidecar to be ready...");
+            CancellationToken timeout = new CancellationTokenSource(TimeSpan.FromMinutes(1)).Token;
+            await client.WaitForSidecarAsync(timeout);
+
             while (true)
             {
                 SocialMediaMessage message = GeneratePost();

pubsub-workflow/Program.cs

@@ -30,9 +30,18 @@ static void Main(string[] args)
             ObservabilityUtils.StartMetricsServer();
 
             var host = CreateHostBuilder(args).Build();
-
+            
             var logger = host.Services.GetRequiredService<ILogger<PubsubWorkflow>>();
 
+            // When ran in k8s, this app might start before Dapr sidecar is ready
+            // and this will lead to errors. Let's wait a bit for the sidecar to
+            // be ready before we start publishing.
+            logger.LogInformation("Waiting for Dapr sidecar to be ready...");
+            CancellationToken timeout = new CancellationTokenSource(TimeSpan.FromMinutes(1)).Token;
+            var client = new DaprClientBuilder().Build();
+            client.WaitForSidecarAsync(timeout).Wait();
+
+
             logger.LogInformation("Starting Pubsub Workflow");
 
             var rapidTimer = StartPublishingMessages(10, rapidPubsubName, "rapidtopic");