feat: implement zero-downtime Green/Blue deployment using local TCP proxy

.gitea/workflows/deploy.yml

@@ -100,6 +100,7 @@ jobs:
 
       - name: Package artifact
         run: |
+          cp deploy_gb.sh ./publish/deploy_gb.sh
           tar -czf taxbaik_deploy.tgz -C ./publish .
           echo "✓ Package: $(du -sh taxbaik_deploy.tgz | cut -f1)"
 
@@ -163,11 +164,9 @@ jobs:
           test -s "\$DEPLOY_DIR/appsettings.Production.json" \
             || { echo "FATAL: appsettings.Production.json 없음" >&2; exit 1; }
 
-          echo "--- [3/5] 심볼릭 링크 전환 ---"
-          ln -sfn "\$DEPLOY_DIR" "\$DEPLOY_HOME/taxbaik_active"
-
-          echo "--- [4/5] 서비스 재시작 ---"
-          sudo /usr/bin/systemctl restart taxbaik
+          echo "--- [3/4] Green-Blue 배포 실행 ---"
+          chmod +x "\$DEPLOY_DIR/deploy_gb.sh"
+          "\$DEPLOY_DIR/deploy_gb.sh" "\$DEPLOY_DIR"
 
           echo "--- [5/5] 헬스 체크 (최대 60초) ---"
           ATTEMPTS=20

TaxBaik.Proxy/Program.cs

@@ -0,0 +1,93 @@
+using System;
+using System.IO;
+using System.Net;
+using System.Net.Sockets;
+using System.Threading;
+using System.Threading.Tasks;
+
+class Program
+{
+    private const string PortFile = "/home/kjh2064/taxbaik_port";
+    private static int _fallbackPort = 5003;
+
+    static async Task Main(string[] args)
+    {
+        // Allow setting fallback port via args
+        if (args.Length > 0 && int.TryParse(args[0], out var port))
+        {
+            _fallbackPort = port;
+        }
+
+        var listener = new TcpListener(IPAddress.Loopback, 5001);
+        listener.Start();
+        Console.WriteLine($"[TaxBaik Proxy] Listening on 127.0.0.1:5001 (Forwarding to target in {PortFile})");
+
+        while (true)
+        {
+            try
+            {
+                var client = await listener.AcceptTcpClientAsync();
+                _ = HandleClientAsync(client);
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine($"[TaxBaik Proxy] Accept error: {ex.Message}");
+                await Task.Delay(100);
+            }
+        }
+    }
+
+    private static int GetTargetPort()
+    {
+        try
+        {
+            if (File.Exists(PortFile))
+            {
+                var content = File.ReadAllText(PortFile).Trim();
+                if (int.TryParse(content, out var port) && port > 1024 && port < 65535)
+                {
+                    return port;
+                }
+            }
+        }
+        catch { }
+        return _fallbackPort;
+    }
+
+    private static async Task HandleClientAsync(TcpClient client)
+    {
+        client.NoDelay = true;
+        int targetPort = GetTargetPort();
+        using var backend = new TcpClient();
+        backend.NoDelay = true;
+
+        try
+        {
+            using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+            await backend.ConnectAsync(IPAddress.Loopback, targetPort, cts.Token);
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"[TaxBaik Proxy] Failed to connect to backend on port {targetPort}: {ex.Message}");
+            client.Close();
+            return;
+        }
+
+        try
+        {
+            using var clientStream = client.GetStream();
+            using var backendStream = backend.GetStream();
+
+            var toBackend = clientStream.CopyToAsync(backendStream);
+            var toClient = backendStream.CopyToAsync(clientStream);
+
+            await Task.WhenAny(toBackend, toClient);
+        }
+        catch { }
+        finally
+        {
+            client.Close();
+            backend.Close();
+        }
+    }
+}

TaxBaik.Proxy/TaxBaik.Proxy.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

deploy_gb.sh

@@ -0,0 +1,96 @@
+#!/bin/bash
+set -e
+
+DEPLOY_HOME="/home/kjh2064"
+PORT_FILE="$DEPLOY_HOME/taxbaik_port"
+TIMESTAMP=$(date +%Y%m%d_%H%M%S)
+
+echo "===== 🚀 TaxBaik Green/Blue Deployment Script ====="
+
+# 1. Determine active port
+ACTIVE_PORT=5003
+if [ -f "$PORT_FILE" ]; then
+  ACTIVE_PORT=$(cat "$PORT_FILE" | tr -d '[:space:]')
+fi
+
+# 2. Determine target port
+TARGET_PORT=5003
+if [ "$ACTIVE_PORT" -eq 5003 ]; then
+  TARGET_PORT=5004
+else
+  TARGET_PORT=5003
+fi
+
+echo "Active Port: $ACTIVE_PORT"
+echo "Target Port: $TARGET_PORT"
+
+# 3. New deploy dir is passed as first argument
+DEPLOY_DIR="$1"
+if [ -z "$DEPLOY_DIR" ]; then
+  echo "Error: Deployment directory argument required"
+  exit 1
+fi
+
+echo "Deploy Directory: $DEPLOY_DIR"
+
+# 4. Start the new app on the target port
+echo "=== Starting New App on Port $TARGET_PORT ==="
+cd "$DEPLOY_DIR"
+export ASPNETCORE_ENVIRONMENT=Production
+export ASPNETCORE_URLS="http://127.0.0.1:$TARGET_PORT"
+
+# Run dotnet process
+nohup /usr/bin/dotnet TaxBaik.Web.dll > "web_${TARGET_PORT}.log" 2>&1 &
+NEW_PID=$!
+sleep 2
+
+# Verify process is running
+if ! ps -p $NEW_PID > /dev/null; then
+  echo "❌ Failed to start dotnet process on port $TARGET_PORT"
+  exit 1
+fi
+
+# 5. Health Check Loop
+echo "=== Health Checking Port $TARGET_PORT ==="
+ATTEMPTS=20
+SUCCESS=false
+for i in $(seq 1 $ATTEMPTS); do
+  STATUS=$(curl -sf -o /dev/null -w '%{http_code}' "http://127.0.0.1:${TARGET_PORT}/taxbaik/healthz" 2>/dev/null || echo "000")
+  if [ "$STATUS" = "200" ]; then
+    echo "✓ Health check passed on port $TARGET_PORT (Attempt $i/$ATTEMPTS)"
+    SUCCESS=true
+    break
+  fi
+  echo "  Waiting for health check... ($i/$ATTEMPTS, Status: $STATUS)"
+  sleep 2
+done
+
+if [ "$SUCCESS" = "false" ]; then
+  echo "❌ Health check failed. Rolling back..."
+  kill -9 $NEW_PID || true
+  exit 1
+fi
+
+# 6. Switch Traffic
+echo "=== Switching Traffic to Port $TARGET_PORT ==="
+echo "$TARGET_PORT" > "$PORT_FILE"
+echo "✓ Traffic routed to $TARGET_PORT"
+
+# 7. Terminate Old App
+echo "=== Stopping Old App on Port $ACTIVE_PORT ==="
+# Find PID listening on ACTIVE_PORT
+OLD_PID=$(ss -tlnp | grep ":$ACTIVE_PORT " | grep -oP 'pid=\K\d+' | head -n1)
+if [ -n "$OLD_PID" ]; then
+  echo "Killing old process PID: $OLD_PID"
+  kill -15 $OLD_PID || kill -9 $OLD_PID
+  echo "✓ Old process terminated"
+else
+  echo "No old process found on port $ACTIVE_PORT"
+fi
+
+# 8. Cleanup old deployment directories (Keep last 5)
+echo "=== Cleaning Up Old Deployments ==="
+ls -1dt $DEPLOY_HOME/deployments/taxbaik_* 2>/dev/null | tail -n +6 | xargs rm -rf 2>/dev/null || true
+echo "✓ Cleanup completed"
+
+echo "===== ✅ Green/Blue Deployment Completed Successfully ====="