forex api config + refactor (#45)

backend/src/main/kotlin/me/sujanpoudel/playdeals/Conf.kt

@@ -11,7 +11,8 @@ data class Conf(
   val api: Api,
   val environment: Environment,
   val backgroundTask: BackgroundTask,
-  val firebaseAuthCredential: String
+  val firebaseAuthCredential: String,
+  val forexApiKey: String
 ) {
   data class DB(
     val host: String,

backend/src/main/kotlin/me/sujanpoudel/playdeals/common/Conf.kt

@@ -1,3 +1,5 @@
+@file:Suppress("UNCHECKED_CAST")
+
 package me.sujanpoudel.playdeals.common
 
 import me.sujanpoudel.playdeals.Conf
@@ -7,74 +9,67 @@ import java.util.Base64
 
 class BootstrapException(val violations: List<String>) : RuntimeException()
 
-fun buildConf(env: Map<String, String>) = com.github.michaelbull.result.runCatching {
+fun buildConf(envs: Map<String, String>) = com.github.michaelbull.result.runCatching {
   val violations = mutableListOf<String>()
 
-  val environment = env.getOrDefault("ENV", Environment.PRODUCTION.name).asEnumOrNull<Environment>()
-
-  if (environment == null) {
-    violations += "Invalid ENV"
-  }
-
-  val dashboardEnabled = env.getOrDefault("DASHBOARD", "true").toBooleanStrictOrNull()
-  if (dashboardEnabled == null) {
-    violations += "Invalid DASHBOARD"
+  @Suppress("UNCHECKED_CAST")
+  fun <T> env(
+    envVarName: String,
+    default: String? = null,
+    converter: (String) -> T? = { it as? T }
+  ): T? = (
+    envs[envVarName] ?: default ?: run {
+      violations += "No '$envVarName' env var defined!".also { logger.error { it } }
+      null
+    }
+    )?.let(converter) ?: run {
+    violations += "Invalid '$envVarName'"
+    null
   }
 
-  val appPort = env.getOrDefault("APP_PORT", "8888").toIntOrNull()
-
-  if (appPort == null) {
-    violations += "Invalid APP_PORT"
-  }
+  val environment = env("ENV", Environment.PRODUCTION.name) { it.asEnumOrNull<Environment>() }
 
-  val dbPort = env.getOrDefault("DB_PORT", "5432").toIntOrNull()
-  if (dbPort == null) {
-    violations += "Invalid DB_PORT"
-  }
+  val appPort = env("APP_PORT", "8888") { it.toIntOrNull() }
+  val cors = env<String>("CORS", ".*.")
 
-  val dbName = env.getOrDefault("DB_NAME", "play_deals")
-  val dbPoolSize = (env["DB_POOL_SIZE"] ?: "5").toIntOrNull()
-  if (dbPoolSize == null) {
-    violations += "Invalid DB_POOL_SIZE"
-  }
+  val dbPort = env("DB_PORT", "5432") { it.toIntOrNull() }
+  val dbName = env<String>("DB_NAME", "play_deals")
+  val dbPoolSize = env("DB_POOL_SIZE", "5") { it.toIntOrNull() }
+  val dbHost = env<String>("DB_HOST")
+  val dbUsername = env<String>("DB_USERNAME")
+  val dbPassword = env<String>("DB_PASSWORD", "password")
 
-  fun envVar(envVarName: String): String? {
-    val value = env[envVarName]
+  val dashboardEnabled = env("DASHBOARD", "true") { it.toBooleanStrictOrNull() }
+  val dashboardUser = env<String>("DASHBOARD_USER", "admin")
+  val dashboardPassword = env<String>("DASHBOARD_PASS", "admin")
 
-    return if (value.isNullOrBlank()) {
-      violations += "No $envVarName env var defined!".also { logger.error { it } }
-      null
-    } else {
-      value
-    }
+  val firebaseAuthCredential = env("FIREBASE_ADMIN_AUTH_CREDENTIALS") {
+    Base64.getDecoder().decode(it).decodeToString()
   }
 
-  val dbHost: String = envVar("DB_HOST").orEmpty()
-  val dbUsername: String = envVar("DB_USERNAME").orEmpty()
-  val firebaseAuthCredential = envVar("FIREBASE_ADMIN_AUTH_CREDENTIALS")?.let {
-    Base64.getDecoder().decode(it).decodeToString()
-  }.orEmpty()
+  val forexApiKey = env<String>("FOREX_API_KEY")
 
   if (violations.isNotEmpty()) {
     throw BootstrapException(violations)
   } else {
     Conf(
-      api = Conf.Api(appPort!!, cors = env.getOrDefault("CORS", ".*.")),
+      api = Conf.Api(appPort!!, cors = cors!!),
       environment = environment!!,
       db = Conf.DB(
-        host = dbHost,
+        host = dbHost!!,
         port = dbPort!!,
-        name = dbName,
-        username = dbUsername,
-        password = env.getOrDefault("DB_PASSWORD", "password"),
+        name = dbName!!,
+        username = dbUsername!!,
+        password = dbPassword!!,
         poolSize = dbPoolSize!!
       ),
       backgroundTask = Conf.BackgroundTask(
-        dashboardEnabled!!,
-        env.getOrDefault("DASHBOARD_USER", "admin"),
-        env.getOrDefault("DASHBOARD_PASS", "admin")
+        dashboardEnabled = dashboardEnabled!!,
+        dashboardUserName = dashboardUser!!,
+        dashboardPassword = dashboardPassword!!
       ),
-      firebaseAuthCredential = firebaseAuthCredential
+      firebaseAuthCredential = firebaseAuthCredential!!,
+      forexApiKey = forexApiKey!!
     )
   }
 }

backend/src/test/kotlin/me/sujanpoudel/playdeals/IntegrationTest.kt

@@ -56,7 +56,8 @@ abstract class IntegrationTest(private val vertx: Vertx) {
       "admin",
       "admin"
     ),
-    firebaseAuthCredential = ""
+    firebaseAuthCredential = "",
+    forexApiKey = ""
   )
 
   var di = configureDI(vertx, conf)

backend/src/test/kotlin/me/sujanpoudel/playdeals/MainTest.kt

@@ -3,7 +3,6 @@ package me.sujanpoudel.playdeals
 import com.github.michaelbull.result.unwrap
 import com.github.michaelbull.result.unwrapError
 import io.kotest.matchers.collections.shouldContainExactlyInAnyOrder
-import io.kotest.matchers.collections.shouldHaveSize
 import io.kotest.matchers.collections.shouldNotBeEmpty
 import io.kotest.matchers.shouldBe
 import me.sujanpoudel.playdeals.common.BootstrapException
@@ -14,6 +13,7 @@ class MainTest {
   @Test
   fun `Should return a proper conf with all values from env`() {
     val env = mutableMapOf(
+      "ENV" to "DEVELOPMENT",
       "APP_PORT" to "123",
       "CORS" to "*.example.com",
 
@@ -28,14 +28,14 @@ class MainTest {
       "DB_PORT" to "3333",
       "DB_NAME" to "db-name",
 
-      "APP_PORT" to "123",
-
       "FIREBASE_ADMIN_AUTH_CREDENTIALS" to "dGVzdF9jcmVk",
-      "ENV" to "DEVELOPMENT"
+      "FOREX_API_KEY" to "forex_key"
     )
 
     val conf = buildConf(env).unwrap()
 
+    conf.environment shouldBe Environment.DEVELOPMENT
+    conf.api.port shouldBe 123
     conf.api.cors shouldBe "*.example.com"
 
     conf.backgroundTask.dashboardEnabled shouldBe true
@@ -49,41 +49,40 @@ class MainTest {
     conf.db.username shouldBe "u"
     conf.db.port shouldBe 3333
 
-    conf.api.port shouldBe 123
-
-    conf.environment shouldBe Environment.DEVELOPMENT
-  }
-
-  @Test
-  fun `Should fail on first critical incorrect val from env`() {
-    val env = mutableMapOf(
-      "ENV" to "prod"
-    )
-
-    val err = buildConf(env).unwrapError()
-    err.printStackTrace()
-    val violations = (err as BootstrapException).violations
-    violations.shouldHaveSize(4) shouldContainExactlyInAnyOrder listOf(
-      "Invalid ENV",
-      "No DB_HOST env var defined!",
-      "No DB_USERNAME env var defined!",
-      "No FIREBASE_ADMIN_AUTH_CREDENTIALS env var defined!"
-    )
+    conf.firebaseAuthCredential shouldBe "test_cred"
+    conf.forexApiKey shouldBe "forex_key"
   }
 
   @Test
   fun `Should return a proper conf with some defaults being taken`() {
     val env = mutableMapOf(
+      "DB_PORT" to "3333",
       "DB_HOST" to "localhost",
       "DB_USERNAME" to "u",
       "DB_PASSWORD" to "p",
-      "DB_PORT" to "3333",
-      "DB_NAME" to "db-name",
-      "FIREBASE_ADMIN_AUTH_CREDENTIALS" to "dGVzdF9jcmVk"
+      "FIREBASE_ADMIN_AUTH_CREDENTIALS" to "dGVzdF9jcmVk",
+      "FOREX_API_KEY" to "forex_key"
     )
 
     val conf = buildConf(env).unwrap()
+
+    conf.environment shouldBe Environment.PRODUCTION
     conf.api.port shouldBe 8888
+    conf.api.cors shouldBe ".*."
+
+    conf.backgroundTask.dashboardEnabled shouldBe true
+    conf.backgroundTask.dashboardUserName shouldBe "admin"
+    conf.backgroundTask.dashboardPassword shouldBe "admin"
+
+    conf.db.name shouldBe "play_deals"
+    conf.db.host shouldBe "localhost"
+    conf.db.password shouldBe "p"
+    conf.db.poolSize shouldBe 5
+    conf.db.username shouldBe "u"
+    conf.db.port shouldBe 3333
+
+    conf.firebaseAuthCredential shouldBe "test_cred"
+    conf.forexApiKey shouldBe "forex_key"
   }
 
   @Test
@@ -96,11 +95,16 @@ class MainTest {
     val violations = ((buildConf(env).unwrapError()) as BootstrapException).violations
     violations.shouldNotBeEmpty()
     violations shouldContainExactlyInAnyOrder listOf(
-      "Invalid APP_PORT",
-      "Invalid ENV",
-      "No DB_HOST env var defined!",
-      "No DB_USERNAME env var defined!",
-      "No FIREBASE_ADMIN_AUTH_CREDENTIALS env var defined!"
+      "Invalid 'ENV'",
+      "Invalid 'APP_PORT'",
+      "No 'DB_HOST' env var defined!",
+      "Invalid 'DB_HOST'",
+      "No 'DB_USERNAME' env var defined!",
+      "Invalid 'DB_USERNAME'",
+      "No 'FIREBASE_ADMIN_AUTH_CREDENTIALS' env var defined!",
+      "Invalid 'FIREBASE_ADMIN_AUTH_CREDENTIALS'",
+      "No 'FOREX_API_KEY' env var defined!",
+      "Invalid 'FOREX_API_KEY'"
     )
   }
 }