Add dart3 test with for hybrid horizontal scaling with load balancer (#10634)

* revert dart3.dockerfile to scratch

* delete run.sh

* bump dart version

* update HttpStatus for requestTimeout

* remove requestTimeout and make _handleRequest synchronous again

* remove unnecessary Future and async

* move workerGroupTag after pre-existing args

* expose args in _startServer function

* add base structure for hybrid scaling

* fix benchmark_config.json

* implement loadbalancer

* replace CMD with ENTRYPOINT in Dockerfile

* allow --port to be parsed at runtime

* update run.sh to make busybox happy

* update run.sh to make busybox happy (1)

* comments added to run.sh

Author: iapicca

frameworks/Dart/dart3/analysis_options.yaml

@@ -1 +1,3 @@
 include: package:lints/recommended.yaml
+formatter:
+  trailing_commas: preserve

frameworks/Dart/dart3/benchmark_config.json

@@ -24,6 +24,18 @@
       "language": "Dart",
       "os": "Linux",
       "database_os": "Linux"
+    },
+    "hybrid": {
+      "display_name": "dart3_hybrid",
+      "json_url": "/json",
+      "plaintext_url": "/plaintext",
+      "port": 8080,
+      "approach": "Stripped",
+      "classification": "Platform",
+      "database": "None",
+      "language": "Dart",
+      "os": "Linux",
+      "database_os": "Linux"
     }
-}]
+  }]
 }

frameworks/Dart/dart3/bin/server.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 import 'dart:io';
 import 'dart:isolate';
 import 'dart:math' show min;
+import 'package:args/args.dart' show ArgParser;
 
 /// Environment declarations are evaluated at compile-time. Use 'const' to
 /// ensure values are baked into AOT/Native binaries for the benchmark.
@@ -73,7 +74,7 @@ void _startServer(List<String> args) async {
   /// Binds the [HttpServer] on `0.0.0.0:8080`.
   final server = await HttpServer.bind(
     InternetAddress.anyIPv4,
-    8080,
+    _portParser(args, defaultPort: 8080),
     shared: true,
   );
 
@@ -131,10 +132,28 @@ void _sendText(HttpRequest request, String response) => _sendResponse(
 );
 
 /// Responds with the JSON test to the [request].
-void _jsonTest(HttpRequest request) =>
-    _sendJson(request, const {'message': 'Hello, World!'});
+void _jsonTest(HttpRequest request) => _sendJson(
+  request,
+  const {'message': 'Hello, World!'},
+);
 
 /// Responds with the plaintext test to the [request].
-void _plaintextTest(HttpRequest request) => _sendText(request, 'Hello, World!');
+void _plaintextTest(HttpRequest request) => _sendText(
+  request,
+  'Hello, World!',
+);
 
 final _jsonEncoder = JsonUtf8Encoder();
+
+int _portParser(
+  List<String> args, {
+  required int defaultPort,
+  portTag = 'port',
+}) {
+  final parser = ArgParser()
+    ..addOption(
+      portTag,
+      defaultsTo: '$defaultPort',
+    );
+  return int.tryParse(parser.parse(args)[portTag]) ?? defaultPort;
+}

frameworks/Dart/dart3/dart3-hybrid.dockerfile

@@ -0,0 +1,34 @@
+
+FROM dart:3.10.8 AS build
+WORKDIR /app
+
+# Define the maximum number of Dart Isolates at build time
+ARG MAX_ISOLATES=10
+
+COPY pubspec.yaml .
+COPY bin bin
+
+RUN dart compile exe bin/server.dart \
+    --define=MAX_ISOLATES=${MAX_ISOLATES} \
+    -o server
+
+FROM traefik:latest AS traefik_source
+
+FROM busybox:glibc
+WORKDIR /app
+# Matches `ARG MAX_ISOLATES` in `build`
+ENV MAX_ISOLATES=10
+# Define the minimum number of processes dedicated to `Traefik`
+ENV MIN_TRAEFIK_PROCESSES=4
+
+COPY --from=build /runtime/ /
+COPY --from=build /app/server /app/server
+COPY --from=traefik_source /usr/local/bin/traefik /usr/local/bin/traefik
+COPY /dart_hybrid/traefik.yaml /etc/traefik/traefik.yaml
+COPY /dart_hybrid/traefik_dynamic.yaml /etc/traefik/traefik_dynamic.yaml
+COPY /dart_hybrid/run.sh /app/run.sh
+
+RUN chmod +x /app/run.sh
+
+EXPOSE 8080
+CMD ["/app/run.sh"]

frameworks/Dart/dart3/dart_hybrid/run.sh

@@ -0,0 +1,41 @@
+#!/bin/sh
+
+# --- 1. Environment & Hardware Detection ---
+TOTAL_PROCESSES=$(grep -c ^processor /proc/cpuinfo)
+MAX_ISO=${MAX_ISOLATES:-8}
+RESERVED=${MIN_TRAEFIK_PROCESSES:-4}
+
+# --- 2. Scaling Logic ---
+if [ "$TOTAL_PROCESSES" -le "$((MAX_ISO * 2))" ]; then
+    exec /app/server
+else
+    DART_POOL=$((TOTAL_PROCESSES - RESERVED))
+    NUM_WORKERS=$(( DART_POOL / MAX_ISO ))
+    DART_PROCESSES=$(( NUM_WORKERS * MAX_ISO )) 
+    TRAEFIK_PROCESSES=$(( TOTAL_PROCESSES - DART_PROCESSES ))
+
+    export GOMAXPROCS=$TRAEFIK_PROCESSES
+
+# --- 3. Generate Backend List ---
+    TMP_URLS="/tmp/urls.yaml"
+    true > "$TMP_URLS"
+
+    for i in $(seq 1 $NUM_WORKERS); do
+        PORT=$((9000 + i))
+        echo "          - url: \"http://127.0.0.1:$PORT\"" >> "$TMP_URLS"
+
+        /app/server --port=$PORT &
+    done
+
+# --- 4. Traefik Configuration ---
+    sed -i "/# DART_WORKERS_PLACEHOLDER/ {
+      r $TMP_URLS
+      d
+    }" /etc/traefik/traefik_dynamic.yaml
+    rm "$TMP_URLS"
+    
+# --- 5. Readiness & Execution ---
+    until nc -z 127.0.0.1 9001; do sleep 0.1; done
+
+    exec traefik --configfile=/etc/traefik/traefik.yaml
+fi

frameworks/Dart/dart3/dart_hybrid/traefik.yaml

@@ -0,0 +1,17 @@
+global:
+  checkNewVersion: false
+  sendAnonymousUsage: false
+
+entryPoints:
+  web:
+    address: ":8080"
+    transport:
+      respondingTimeouts:
+        readTimeout: "0s"
+        writeTimeout: "0s"
+        idleTimeout: "0s"
+
+providers:
+  file:
+    filename: /etc/traefik/traefik_dynamic.yaml
+    watch: false

frameworks/Dart/dart3/dart_hybrid/traefik_dynamic.yaml

@@ -0,0 +1,19 @@
+http:
+  routers:
+    to-dart:
+      rule: "PathPrefix(`/`)"
+      service: dart-service
+      middlewares:
+        - dart-header
+      entryPoints:
+        - web
+  middlewares:
+    dart-header:
+      headers:
+        customResponseHeaders:
+          Server: "dart"
+  services:
+    dart-service:
+      loadBalancer:
+        servers:
+          # DART_WORKERS_PLACEHOLDER

frameworks/Dart/dart3/pubspec.yaml

@@ -3,5 +3,9 @@ description: A benchmark of dart
 environment:
   sdk: ^3.10.8
 
+dependencies:
+  args: ^2.7.0
+
 dev_dependencies:
   lints: ^6.0.0
+