Akka.NET Cluster Bootstrapper

AzureBootstrapper.cs

namespace WebCrawler.AzureBootstrap
{
    public static class AzureRuntimeBootLoader
    {
        public static async Task<Config> CreateRuntimeConfig(string seedRoleName, string akkaEndpoint)
        {
            // Need to wait until at least 1 instance of our seed role is up and available
            while(!IsSeedRoleAvailable(seedRoleName))
            {
                await Task.Delay(TimeSpan.FromSeconds(1.5));
            }

            return CreateConfig(seedRoleName, akkaEndpoint);
        }

        public static bool IsSeedRoleAvailable(string seedRoleName)
        {
            if (!RoleEnvironment.Roles.ContainsKey(seedRoleName))
                throw new ArgumentException("Undefined role " + seedRoleName + " in Azure service definition");
            return RoleEnvironment.Roles[seedRoleName].Instances.Any();
        }

        private static Config CreateConfig(string seedRoleName, string akkaEndpoint)
        {
            var section = (AkkaConfigurationSection)ConfigurationManager.GetSection("akka");
            var clusterConfig = section.AkkaConfig;

            var selfAzureAddress = RoleEnvironment.CurrentRoleInstance.InstanceEndpoints[akkaEndpoint];
            var selfAkkaAddress = selfAzureAddress.IPEndpoint.Address;
            var selfPort = selfAzureAddress.IPEndpoint.Port;
            var seedNodes = new List<string>();

            var trackerRoles = RoleEnvironment.Roles[seedRoleName].Instances;
            foreach (var trackerEndpoint in trackerRoles.Select(x => x.InstanceEndpoints[akkaEndpoint]))
            {
                seedNodes.Add(string.Format(@"""akka.tcp://{0}@{1}:{2}""", "webcrawler", trackerEndpoint.IPEndpoint.Address, trackerEndpoint.IPEndpoint.Port));
            }

            var remoteConfig = ConfigurationFactory.ParseString(string.Format(@"akka.remote.helios.tcp.public-hostname = ""{0}"" 
            akka.remote.helios.tcp.port = {1}", selfAkkaAddress, selfPort));
            var clusterSeedConfig = ConfigurationFactory.ParseString(string.Format(@"akka.cluster.seed-nodes = [{0}]", string.Join(",", seedNodes)));
            var finalConfig = clusterSeedConfig.WithFallback(remoteConfig).WithFallback(clusterConfig);
            return finalConfig;
        }
    }
}