feat: Working on cli client and tests

Sources/CliClient/CliClient.swift

@@ -14,25 +14,38 @@ public extension DependencyValues {
   }
 }
 
+/// Represents the interface needed for the command line application.
+///
+///
 @DependencyClient
 public struct CliClient {
 
+  /// Parse a log level from the given `EnvVars`.
   public var logLevel: @Sendable (EnvVars) -> Logger.Level = { _ in .debug }
+
+  /// Generate the `EnvVars` with the given parameters.
   public var makeEnvVars: @Sendable (EnvVarsRequest) async throws -> EnvVars
+
+  /// Generate the `MQTTClient` with the given parameters.
   public var makeClient: @Sendable (ClientRequest) throws -> MQTTClient
+
+  /// Attempt to parse a string to an `MQTTClient.Version`.
   public var parseMqttClientVersion: @Sendable (String) -> MQTTClient.Version?
 
+  /// Represents the parameters needed to create an `MQTTClient`.
+  ///
+  ///
   public struct ClientRequest: Sendable {
-    public let envVars: EnvVars
+    public let environment: EnvVars
     public let eventLoopGroup: MultiThreadedEventLoopGroup
     public let logger: Logger?
 
     public init(
-      envVars: EnvVars,
+      environment: EnvVars,
       eventLoopGroup: MultiThreadedEventLoopGroup,
       logger: Logger?
     ) {
-      self.envVars = envVars
+      self.environment = environment
       self.eventLoopGroup = eventLoopGroup
       self.logger = logger
     }
@@ -63,7 +76,7 @@ extension CliClient: DependencyKey {
     Self(
       logLevel: { Logger.Level.from(environment: $0) },
       makeEnvVars: {
-        try EnvVars.load(
+        try await EnvVars.load(
           dotEnvFile: $0.envFilePath,
           logger: $0.logger,
           version: $0.mqttClientVersion
@@ -71,7 +84,7 @@ extension CliClient: DependencyKey {
       },
       makeClient: {
         MQTTClient(
-          envVars: $0.envVars,
+          environment: $0.environment,
           eventLoopGroup: $0.eventLoopGroup,
           logger: $0.logger
         )
@@ -81,32 +94,44 @@ extension CliClient: DependencyKey {
   }
 }
 
+// MARK: - Helpers
+
+extension EnvironmentDependency {
+  func dotEnvDict(path: String?) async throws -> [String: String] {
+    guard let path,
+          let file = FileType(path: path)
+    else { return [:] }
+    return try await load(file)
+  }
+}
+
 extension EnvVars {
 
   /// Load the `EnvVars` from the environment.
   ///
   /// - Paramaters:
+  ///   - dotEnvFile: An optional environment file to load.
   ///   - logger: An optional logger to use for debugging.
   ///   - version: A version that is specified from command line, ignoring any environment variable.
   static func load(
     dotEnvFile: String?,
     logger: Logger?,
     version: String?
-  ) throws -> EnvVars {
+  ) async throws -> EnvVars {
+    @Dependency(\.environment) var environment
+
     let defaultEnvVars = EnvVars()
     let encoder = JSONEncoder()
     let decoder = JSONDecoder()
 
-    if let dotEnvFile {
-      try DotEnv.load(path: dotEnvFile)
-    }
-
     let defaultEnvDict = (try? encoder.encode(defaultEnvVars))
       .flatMap { try? decoder.decode([String: String].self, from: $0) }
       ?? [:]
 
+    let dotEnvDict = try await environment.dotEnvDict(path: dotEnvFile)
     let envVarsDict = defaultEnvDict
-      .merging(ProcessInfo.processInfo.environment, uniquingKeysWith: { $1 })
+      .merging(environment.processInfo(), uniquingKeysWith: { $1 })
+      .merging(dotEnvDict, uniquingKeysWith: { $1 })
 
     var envVars = (try? JSONSerialization.data(withJSONObject: envVarsDict))
       .flatMap { try? decoder.decode(EnvVars.self, from: $0) }
@@ -125,7 +150,7 @@ extension EnvVars {
 @_spi(Internal)
 public extension MQTTClient {
   convenience init(
-    envVars: EnvVars,
+    environment envVars: EnvVars,
     eventLoopGroup: EventLoopGroup,
     logger: Logger?
   ) {