test(gateway): run the assembled gateway against a fake controller and Influx

Asserts the POMPA point keeps exactly the 8 legacy field names with their values, heat_pump is written, and /health and /snapshot answer. MockModbusServer becomes public to be used from another package.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/test/java/home/gateway/GatewayEndToEndTest.java

@@ -0,0 +1,156 @@
+package home.gateway;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.sun.net.httpserver.HttpServer;
+import home.gateway.adapters.heatpump.HeatPumpSettings;
+import home.gateway.adapters.heatpump.RegisterBlock;
+import home.gateway.adapters.modbus.MockModbusServer;
+import home.gateway.config.GatewayConfig;
+import home.gateway.config.GatewayConfigLoader;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.time.Clock;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.stream.Collectors;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/** The assembled gateway against a fake controller and a fake InfluxDB, both on localhost. */
+class GatewayEndToEndTest {
+
+    private static final Set<String> LEGACY_FIELDS = Set.of(
+            "External\\ temperature=-4.3", "Temp\\ wew=21.5", "Temp\\ co=35.0", "Temp\\ cwu=48.0",
+            "Temp\\ in=8.5", "Temp\\ out=5.5", "Temp\\ pc\\ out=17.0", "Temp\\ zsr=5.2");
+
+    private final ObjectMapper json = new ObjectMapper();
+    private final HttpClient http = HttpClient.newHttpClient();
+    private final List<String> influxWrites = new CopyOnWriteArrayList<>();
+    private MockModbusServer controller;
+    private HttpServer influx;
+    private Gateway gateway;
+    private int gatewayPort;
+
+    @TempDir
+    Path dir;
+
+    @BeforeEach
+    void startFakes() throws IOException {
+        controller = new MockModbusServer();
+        for (RegisterBlock block : HeatPumpSettings.PRODUCTION_BLOCKS) {
+            for (int address = block.start(); address < block.start() + block.count(); address++) {
+                controller.holding(address, 0);
+            }
+        }
+        controller.holding(4065, 0x8000 | 43);
+        controller.holding(4066, 215);
+        controller.holding(4067, 350);
+        controller.holding(4069, 480);
+        controller.holding(4070, 85);
+        controller.holding(4071, 55);
+        controller.holding(4072, 170);
+        controller.holding(4199, 52);
+        controller.holding(4143, 38);
+
+        influx = HttpServer.create(new InetSocketAddress(InetAddress.getLoopbackAddress(), 0), 0);
+        influx.createContext("/write", exchange -> {
+            influxWrites.add(exchange.getRequestURI().getQuery() + "\n"
+                    + new String(exchange.getRequestBody().readAllBytes(), StandardCharsets.UTF_8));
+            exchange.sendResponseHeaders(204, -1);
+            exchange.close();
+        });
+        influx.start();
+    }
+
+    @AfterEach
+    void stopFakes() throws IOException {
+        if (gateway != null) {
+            gateway.close();
+        }
+        influx.stop(0);
+        controller.close();
+    }
+
+    @Test
+    void polledHeatPumpReachesInfluxAndTheApi() throws Exception {
+        gateway = Gateway.start(loadConfig(), Clock.systemUTC(), () -> { });
+
+        waitForFirstPoll();
+        assertEquals(200, get("/health").statusCode());
+        assertEquals("heat-pump", json.readTree(get("/snapshot").body()).get(0).get("name").asText());
+
+        gateway.close();
+        List<String> lines = influxLines();
+        assertTrue(influxWrites.get(0).startsWith("db=Dom_Pompa&"), influxWrites.get(0));
+        assertEquals(LEGACY_FIELDS, fieldsOf(lineOf(lines, "POMPA")));
+        Set<String> heatPump = fieldsOf(lineOf(lines, "heat_pump"));
+        assertTrue(heatPump.contains("setpoint_cwu_economy=38.0"), heatPump.toString());
+        assertTrue(heatPump.contains("outdoor_temp=-4.3"), heatPump.toString());
+    }
+
+    private Path configFile() throws IOException {
+        try (ServerSocket free = new ServerSocket(0)) {
+            gatewayPort = free.getLocalPort();
+        }
+        return Files.writeString(dir.resolve("gateway.json"), """
+                {"influx": {"baseUri": "http://localhost:%d", "spoolDirectory": "%s"},
+                 "http": {"port": %d},
+                 "devices": {"heatPump": {"enabled": true,
+                   "connection": {"host": "localhost", "port": %d, "minimumPauseMs": 1}}}}"""
+                .formatted(influx.getAddress().getPort(), dir.resolve("spool"), gatewayPort,
+                        controller.port()));
+    }
+
+    private GatewayConfig loadConfig() throws IOException {
+        return GatewayConfigLoader.load(configFile());
+    }
+
+    private void waitForFirstPoll() throws Exception {
+        for (int attempt = 0; attempt < 100; attempt++) {
+            JsonNode devices = json.readTree(get("/snapshot").body());
+            if (devices.size() == 1 && !devices.get(0).get("lastSuccess").isNull()) {
+                return;
+            }
+            Thread.sleep(100);
+        }
+        throw new AssertionError("the heat pump was not polled in 10 s");
+    }
+
+    private HttpResponse<String> get(String path) throws Exception {
+        return http.send(HttpRequest.newBuilder(URI.create("http://localhost:" + gatewayPort + path)).build(),
+                HttpResponse.BodyHandlers.ofString());
+    }
+
+    private List<String> influxLines() {
+        return influxWrites.stream().flatMap(write -> Arrays.stream(write.split("\n")).skip(1)).toList();
+    }
+
+    private static String lineOf(List<String> lines, String measurement) {
+        return lines.stream().filter(line -> line.startsWith(measurement + " ")).findFirst()
+                .orElseThrow(() -> new AssertionError("no " + measurement + " line in " + lines));
+    }
+
+    /** The field part of {@code measurement fields timestamp}; no field key here contains a comma. */
+    private static Set<String> fieldsOf(String line) {
+        String fields = line.substring(line.indexOf(' ') + 1, line.lastIndexOf(' '));
+        return Arrays.stream(fields.split(",")).collect(Collectors.toSet());
+    }
+}

src/test/java/home/gateway/adapters/modbus/MockModbusServer.java

@@ -13,7 +13,7 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /** Local Modbus TCP fake answering FC3 and FC4; unknown addresses get exception code 2. */
-final class MockModbusServer implements Closeable {
+public final class MockModbusServer implements Closeable {
 
     private final ServerSocket server;
     private final Map<Integer, Integer> holding = new ConcurrentHashMap<>();
@@ -24,12 +24,12 @@ final class MockModbusServer implements Closeable {
     private volatile boolean wrongTransactionId;
     private volatile boolean overlapped;
 
-    MockModbusServer() throws IOException {
+    public MockModbusServer() throws IOException {
         server = new ServerSocket(0, 50, InetAddress.getLoopbackAddress());
         Thread.ofVirtual().start(this::acceptLoop);
     }
 
-    int port() {
+    public int port() {
         return server.getLocalPort();
     }
 
@@ -37,7 +37,7 @@ final class MockModbusServer implements Closeable {
         return connections.get();
     }
 
-    void holding(int address, int value) {
+    public void holding(int address, int value) {
         holding.put(address, value);
     }