public Task StartAsync()

in src/WebJobs.Extensions.DurableTask/LocalGrpcListener.cs [56:108]
47 lines of code
6 McCabe index (conditional complexity)

        public Task StartAsync(CancellationToken cancelToken = default)
        {
            const int maxAttempts = 10;
            int numAttempts = 1;
            while (numAttempts <= maxAttempts)
            {
                ChannelOption[] options = new[]
                {
                    new ChannelOption(ChannelOptions.MaxReceiveMessageLength, int.MaxValue),
                    new ChannelOption(ChannelOptions.MaxSendMessageLength, int.MaxValue),
                };

                this.grpcServer = new Server(options);
                this.grpcServer.Services.Add(P.TaskHubSidecarService.BindService(new TaskHubGrpcServer(this)));

                int listeningPort = numAttempts == 1 ? DefaultPort : this.GetRandomPort();
                int portBindingResult = this.grpcServer.Ports.Add("localhost", listeningPort, ServerCredentials.Insecure);
                if (portBindingResult != 0)
                {
                    try
                    {
                        this.grpcServer.Start();
                        this.ListenAddress = $"http://localhost:{listeningPort}";

                        this.extension.TraceHelper.ExtensionInformationalEvent(
                            this.extension.Options.HubName,
                            instanceId: string.Empty,
                            functionName: string.Empty,
                            message: $"Opened local gRPC endpoint: {this.ListenAddress}",
                            writeToUserLogs: true);

                        return Task.CompletedTask;
                    }
                    catch (IOException)
                    {
                        portBindingResult = 0;
                    }
                }

                if (portBindingResult == 0)
                {
                    this.extension.TraceHelper.ExtensionWarningEvent(
                        this.extension.Options.HubName,
                        functionName: string.Empty,
                        instanceId: string.Empty,
                        message: $"Failed to open local port {listeningPort}. This was attempt #{numAttempts} to open a local port.");
                    this.attemptedPorts.Add(listeningPort);
                    numAttempts++;
                }
            }

            throw new IOException($"Unable to find a port to open an RPC endpoint on after {maxAttempts} attempts");
        }