Migrate to JetBrains Exposed

Author: dvitski

build.gradle.kts

@@ -19,6 +19,7 @@ repositories {
 
 dependencies {
     val ktor_version = property("ktor_version")
+    val exposed_version = property("exposed_version")
 
     testImplementation("org.jetbrains.kotlin:kotlin-test")
 
@@ -32,6 +33,12 @@ dependencies {
 
     implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.1")
 
+    implementation("org.jetbrains.exposed:exposed-core:$exposed_version")
+    implementation("org.jetbrains.exposed:exposed-jdbc:$exposed_version")
+    implementation("org.jetbrains.exposed:exposed-kotlin-datetime:$exposed_version")
+    implementation("org.jetbrains.exposed:exposed-json:$exposed_version")
+    implementation("org.jetbrains.exposed:exposed-dao:$exposed_version")
+
     implementation("com.mojang:datafixerupper:7.0.14")
     implementation("com.mojang:brigadier:1.0.18")
 }

gradle.properties

@@ -1,3 +1,4 @@
 kotlin.code.style=official
 ktor_version=2.3.9
-version=1.5.6
+version=2.0
+exposed_version=0.54.0

src/main/kotlin/net/mcbrawls/api/Main.kt

@@ -6,12 +6,18 @@ import kotlinx.serialization.Serializable
  * Ranks on the MC Brawls Minecraft server.
  */
 @Serializable(with = RankSerializer::class)
-enum class Rank {
-    ADMIN,
-    BUILDER,
-    MODERATOR,
-    MCCIT,
-    PARTNER,
-    STAFF,
-    DEFAULT;
-}
+enum class Rank(private val rankId: String) {
+    ADMIN("admin"),
+    BUILDER("builder"),
+    MODERATOR("moderator"),
+    MCCIT("mccit"),
+    PARTNER("partner"),
+    STAFF("staff"),
+    DEFAULT("default");
+
+    companion object {
+        private val BY_ID = entries.associateBy(Rank::rankId)
+
+        fun fromId(id: String): Rank? = BY_ID[id]
+    }
+}

src/main/kotlin/net/mcbrawls/api/Rank.kt

@@ -0,0 +1,31 @@
+package net.mcbrawls.api.database
+
+import org.jetbrains.exposed.sql.Database
+
+/**
+ * Manages the remote Brawls MySQL database.
+ */
+object BrawlsDatabaseFactory {
+    /**
+     * Loads the configuration from disk.
+     */
+    fun createDatabase(schema: String): Database {
+        val url = ConnectionConfig.url
+        return Database.connect(
+            url = "jdbc:mysql://$url/$schema",
+            user = ConnectionConfig.username,
+            password = ConnectionConfig.password,
+        )
+    }
+
+    private object ConnectionConfig {
+        val url = env("URL")
+        val username = env("USERNAME")
+        val password = env("PASSWORD")
+
+        private fun env(name: String): String {
+            val fullName = "BRAWLS_DB_$name"
+            return System.getenv(fullName) ?: throw IllegalArgumentException("Environment variable not found: $fullName")
+        }
+    }
+}