Add PostgreSQL status check

build.gradle.kts

@@ -20,6 +20,7 @@ dependencies {
     implementation("io.ktor:ktor-server-netty-jvm:3.1.3")
     implementation("io.ktor:ktor-server-content-negotiation-jvm:3.1.3")
     implementation("io.ktor:ktor-serialization-kotlinx-json-jvm:3.1.3")
+    implementation("org.postgresql:postgresql:42.7.4")
     implementation("ch.qos.logback:logback-classic:1.5.18")
 
     testImplementation(kotlin("test"))

src/main/kotlin/de/ruvnox/tactical/Main.kt

@@ -13,19 +13,32 @@ import io.ktor.server.routing.routing
 import io.ktor.serialization.kotlinx.json.json
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.json.Json
+import java.sql.DriverManager
 
 @Serializable
 data class ServiceStatusResponse(
     val service: String,
     val status: String,
-    val version: String
+    val version: String,
+    val database: DatabaseStatusResponse
+)
+
+@Serializable
+data class DatabaseStatusResponse(
+    val status: String,
+    val host: String,
+    val port: Int,
+    val name: String
 )
 
 fun main() {
+    val serverHost = System.getenv("SERVER_HOST") ?: "0.0.0.0"
+    val serverPort = System.getenv("SERVER_PORT")?.toIntOrNull() ?: 8080
+
     embeddedServer(
         Netty,
-        port = 8080,
+        port = serverPort,
-        host = "0.0.0.0",
+        host = serverHost,
         module = Application::module
     ).start(wait = true)
 }
@@ -61,9 +74,41 @@ fun Application.module() {
                 ServiceStatusResponse(
                     service = "ruvnox-tactical-server",
                     status = "online",
-                    version = "0.1.0-SNAPSHOT"
+                    version = "0.1.0-SNAPSHOT",
+                    database = checkDatabaseStatus()
                 )
             )
         }
     }
 }
+
+fun checkDatabaseStatus(): DatabaseStatusResponse {
+    val dbHost = System.getenv("DB_HOST") ?: "unset"
+    val dbPort = System.getenv("DB_PORT")?.toIntOrNull() ?: 5432
+    val dbName = System.getenv("DB_NAME") ?: "unset"
+    val dbUser = System.getenv("DB_USER") ?: ""
+    val dbPassword = System.getenv("DB_PASSWORD") ?: ""
+
+    val status = try {
+        DriverManager.getConnection(
+            "jdbc:postgresql://$dbHost:$dbPort/$dbName",
+            dbUser,
+            dbPassword
+        ).use { connection ->
+            connection.createStatement().use { statement ->
+                statement.executeQuery("select 1").use { result ->
+                    if (result.next()) "online" else "error"
+                }
+            }
+        }
+    } catch (_: Exception) {
+        "offline"
+    }
+
+    return DatabaseStatusResponse(
+        status = status,
+        host = dbHost,
+        port = dbPort,
+        name = dbName
+    )
+}