Change AccountService from go to dotnet (auto)

src/accountingservice/AccountingService.csproj

@@ -0,0 +1,29 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+	<PropertyGroup>
+		<OutputType>Exe</OutputType>
+		<TargetFramework>net8.0</TargetFramework>
+		<ImplicitUsings>enable</ImplicitUsings>
+		<Nullable>enable</Nullable>
+		<DockerDefaultTargetOS>Linux</DockerDefaultTargetOS>
+	</PropertyGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Confluent.Kafka" Version="2.3.0" />
+		<PackageReference Include="Confluent.SchemaRegistry.Serdes.Protobuf" Version="2.3.0" />
+		<PackageReference Include="Google.Protobuf" Version="3.26.1" />
+		<PackageReference Include="Grpc.Tools" Version="2.62.0">
+			<PrivateAssets>all</PrivateAssets>
+			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+		</PackageReference>
+		<PackageReference Include="Microsoft.Extensions.Logging" Version="8.0.0" />
+		<PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" Version="1.20.1" />
+		<PackageReference Include="OpenTelemetry.AutoInstrumentation" Version="1.5.0" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<!-- GrpcServices is 'none' so that we do not need to depend on the grpc nuget package, and we only need protobuf support. -->
+		<Protobuf Include="..\..\pb\demo.proto" GrpcServices="none" />
+	</ItemGroup>
+
+</Project>

src/accountingservice/AccountingService.sln

@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.9.34701.34
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AccountingService", "AccountingService.csproj", "{C66C35E2-DF04-4DCF-8F6A-87B6D6433FF6}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{C66C35E2-DF04-4DCF-8F6A-87B6D6433FF6}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C66C35E2-DF04-4DCF-8F6A-87B6D6433FF6}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C66C35E2-DF04-4DCF-8F6A-87B6D6433FF6}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C66C35E2-DF04-4DCF-8F6A-87B6D6433FF6}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {6340CDDC-E917-4532-A056-5526E0A7BDDA}
+	EndGlobalSection
+EndGlobal

src/accountingservice/Consumer.cs

@@ -0,0 +1,89 @@
+using Confluent.Kafka;
+using Confluent.Kafka.SyncOverAsync;
+using Confluent.SchemaRegistry.Serdes;
+using Microsoft.Extensions.Logging;
+using Oteldemo;
+
+namespace AccountingService;
+
+internal class Consumer : IDisposable
+{
+    private const string TopicName = "orders";
+
+    private ILogger _logger;
+    private IConsumer<string, OrderResult> _consumer;
+    private bool _isListening;
+
+    public Consumer(ILogger<Consumer> logger)
+    {
+        _logger = logger;
+
+        var servers = Environment.GetEnvironmentVariable("KAFKA_SERVICE_ADDR")
+            ?? throw new ArgumentNullException("KAFKA_SERVICE_ADDR");
+
+        _consumer = BuildConsumer(servers);
+        _consumer.Subscribe(TopicName);
+
+        _logger.LogInformation($"Connecting to Kafka: {servers}");
+    }
+
+    public void StartListening()
+    {
+        _isListening = true;
+
+        try
+        {
+            while (_isListening)
+            {
+                try
+                {
+                    var consumeResult = _consumer.Consume();
+                    if (consumeResult.IsPartitionEOF)
+                    {
+                        continue;
+                    }
+
+                    ProcessMessage(consumeResult.Message);
+                }
+                catch (ConsumeException e)
+                {
+                    _logger.LogError(e, "Consume error: {0}", e.Error.Reason);
+                }
+            }
+        }
+        catch (OperationCanceledException)
+        {
+            _logger.LogInformation("Closing consumer");
+
+            _consumer.Close();
+        }
+    }
+
+    private void ProcessMessage(Message<string, OrderResult> message)
+    {
+        Log.LogOrderReceivedMessage(_logger, message.Value);
+    }
+
+    private IConsumer<string, OrderResult> BuildConsumer(string servers)
+    {
+        var conf = new ConsumerConfig
+        {
+            GroupId = $"accountingservice",
+            BootstrapServers = servers,
+            // https://github.com/confluentinc/confluent-kafka-dotnet/tree/07de95ed647af80a0db39ce6a8891a630423b952#basic-consumer-example
+            AutoOffsetReset = AutoOffsetReset.Earliest,
+            CancellationDelayMaxMs = 10_000,
+            EnableAutoCommit = true
+        };
+
+        return new ConsumerBuilder<string, OrderResult>(conf)
+            .SetValueDeserializer(new ProtobufDeserializer<OrderResult>().AsSyncOverAsync())
+            .Build();
+    }
+
+    public void Dispose()
+    {
+        _isListening = false;
+        _consumer?.Dispose();
+    }
+}

src/accountingservice/Dockerfile

@@ -1,32 +1,32 @@
-# Copyright The OpenTelemetry Authors
-# SPDX-License-Identifier: Apache-2.0
-
-
-FROM golang:1.22-alpine AS builder
-
-WORKDIR /usr/src/app
-
-RUN apk update \
-    && apk add --no-cache make protobuf-dev
-
-RUN --mount=type=cache,target=/go/pkg/mod/ \
-    --mount=type=bind,source=./src/accountingservice/go.sum,target=go.sum \
-    --mount=type=bind,source=./src/accountingservice/go.mod,target=go.mod \
-    --mount=type=bind,source=./src/accountingservice/tools.go,target=tools.go \
-    go mod download \
-    && go list -e -f '{{range .Imports}}{{.}} {{end}}' tools.go | CGO_ENABLED=0 xargs go install -mod=readonly
-
-RUN --mount=type=cache,target=/go/pkg/mod/ \
-    --mount=type=cache,target=/root/.cache/go-build \
-    --mount=type=bind,rw,source=./src/accountingservice,target=. \
-    --mount=type=bind,rw,source=./pb,target=./pb \
-    protoc -I ./pb ./pb/demo.proto --go_out=./ --go-grpc_out=./ \
-    && go build -ldflags "-s -w" -o /go/bin/accountingservice/ ./
-
-FROM alpine
-
-WORKDIR /usr/src/app/
-
-COPY --from=builder /go/bin/accountingservice/ ./
-
-ENTRYPOINT [ "./accountingservice" ]
+FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base
+USER app
+WORKDIR /app
+
+FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
+ARG BUILD_CONFIGURATION=Release
+WORKDIR /src
+COPY ["AccountingService/AccountingService.csproj", "AccountingService/"]
+RUN dotnet restore "./AccountingService/AccountingService.csproj"
+COPY . .
+WORKDIR "/src/AccountingService"
+RUN dotnet build "./AccountingService.csproj" -c $BUILD_CONFIGURATION -o /app/build
+
+FROM build AS publish
+ARG BUILD_CONFIGURATION=Release
+RUN dotnet publish "./AccountingService.csproj" --use-current-runtime -c $BUILD_CONFIGURATION -o /app/publish /p:UseAppHost=false
+
+FROM base AS final
+WORKDIR /app
+COPY --from=publish /app/publish .
+
+USER root
+RUN mkdir -p "/var/log/opentelemetry/dotnet"
+RUN chown app "/var/log/opentelemetry/dotnet"
+USER app
+
+ENV OTEL_TRACES_EXPORTER=otlp
+ENV OTEL_METRICS_EXPORTER=none
+ENV OTEL_LOGS_EXPORTER=otlp
+ENV OTEL_LOG_LEVEL=debug
+
+ENTRYPOINT ["./instrument.sh", "dotnet", "AccountingService.dll"]

src/accountingservice/Helpers.cs

@@ -0,0 +1,31 @@
+using System.Collections;
+
+namespace AccountingService
+{
+    internal static class Helpers
+    {
+        private static List<string> RelevantPrefixes = ["DOTNET_", "CORECLR_", "OTEL_", "KAFKA_"];
+
+        public static IEnumerable<DictionaryEntry> FilterRelevant(this IDictionary envs)
+        {
+            foreach (DictionaryEntry env in envs)
+            {
+                foreach (var prefix in RelevantPrefixes)
+                {
+                    if (env.Key.ToString()?.StartsWith(prefix, StringComparison.InvariantCultureIgnoreCase) ?? false)
+                    {
+                        yield return env;
+                    }
+                }
+            }
+        }
+
+        public static void OutputInOrder(this IEnumerable<DictionaryEntry> envs)
+        {
+            foreach (var env in envs.OrderBy(x => x.Key))
+            {
+                Console.WriteLine(env);
+            }
+        }
+    }
+}

src/accountingservice/Log.cs

@@ -0,0 +1,13 @@
+using Microsoft.Extensions.Logging;
+using Oteldemo;
+
+namespace AccountingService
+{
+    internal static partial class Log
+    {
+        [LoggerMessage(
+            Level = LogLevel.Information, 
+            Message = "Order details: {@OrderResult}.")]
+        public static partial void LogOrderReceivedMessage(ILogger logger, OrderResult orderResult);
+    }
+}

src/accountingservice/Program.cs

@@ -0,0 +1,21 @@
+using AccountingService;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+
+Console.WriteLine("Accounting service started");
+
+Environment.GetEnvironmentVariables()
+    .FilterRelevant()
+    .OutputInOrder();
+
+var host = Host.CreateDefaultBuilder(args)
+    .ConfigureServices(services =>
+    {
+        services.AddSingleton<Consumer>();
+    })
+    .Build();
+
+var consumer = host.Services.GetRequiredService<Consumer>();
+consumer.StartListening();
+
+host.Run();

src/accountingservice/README.md

@@ -7,7 +7,7 @@ This service consumes new orders from a Kafka topic.
 To build the service binary, run:
 
 ```sh
-go build -o /go/bin/accountingservice/
+dotnet build
 ```
 
 ## Docker Build
@@ -18,22 +18,10 @@ From the root directory, run:
 docker compose build accountingservice
 ```
 
-## Regenerate protos
-
-> [!NOTE]
-> [`protoc`](https://grpc.io/docs/protoc-installation/) is required.
-
-To regenerate gRPC code run:
-
-```sh
-go generate
-```
-
 ## Bump dependencies
 
-To bump all dependencies run:
+To bump all dependencies run in Package manager:
 
 ```sh
-go get -u -t ./...
-go mod tidy
+Update-Package -ProjectName AccountingService
 ```