Add function to create KubernetesClientConfig from string (#41)

Author: AaronKaa

Sources/SwiftkubeClient/Config/KubernetesClientConfig.swift

@@ -114,6 +114,30 @@ public extension KubernetesClientConfig {
 
 		return try? URLConfigLoader(url: url).load(timeout: timeout, redirectConfiguration: redirectConfiguration, logger: logger)
 	}
+    
+    /// Initializes a client configuration from a given String.
+    ///
+    /// It is also possible to override the default values for the underlying `HTTPClient` timeout and redirect config.
+    ///
+    /// - Parameters:
+    ///   - string: The string to load the configuration from.
+    ///   - timeout: The desired timeout configuration to apply. If not provided, then `connect` timeout will
+    /// default to 10 seconds.
+    ///   - redirectConfiguration: Specifies redirect processing settings. If not provided, then it will default
+    /// to a maximum of 5 follows w/o cycles.
+    ///   - logger: The logger to use for the underlying configuration loaders.
+    /// - Returns: An instance of KubernetesClientConfig for the Swiftkube KubernetesClient
+    static func createFromString(
+        fromString string: String,
+        timeout: HTTPClient.Configuration.Timeout? = nil,
+        redirectConfiguration: HTTPClient.Configuration.RedirectConfiguration? = nil,
+        logger: Logger = SwiftkubeClient.loggingDisabled
+    ) -> KubernetesClientConfig? {
+        let timeout = timeout ?? .init()
+        let redirectConfiguration = redirectConfiguration ?? .follow(max: 5, allowCycles: false)
+
+        return try? StringConfigLoader(contents: string).load(timeout: timeout, redirectConfiguration: redirectConfiguration, logger: logger)
+    }
 }
 
 // MARK: - KubernetesClientConfigLoader
@@ -133,6 +157,59 @@ extension KubernetesClientConfigLoader {
 	}
 }
 
+// MARK: - StringConfigLoader
+
+internal struct StringConfigLoader: KubernetesClientConfigLoader {
+
+    let contents: String
+    
+    internal func load(
+        timeout: HTTPClient.Configuration.Timeout,
+        redirectConfiguration: HTTPClient.Configuration.RedirectConfiguration,
+        logger: Logger?
+    ) throws -> KubernetesClientConfig? {
+        let decoder = YAMLDecoder()
+
+        guard let kubeConfig = try? decoder.decode(KubeConfig.self, from: contents) else {
+            return nil
+        }
+
+        guard let currentContext = kubeConfig.currentContext else {
+            return nil
+        }
+
+        guard let context = kubeConfig.contexts?.filter({ $0.name == currentContext }).map(\.context).first else {
+            return nil
+        }
+
+        guard let cluster = kubeConfig.clusters?.filter({ $0.name == context.cluster }).map(\.cluster).first else {
+            return nil
+        }
+
+        guard let masterURL = URL(string: cluster.server) else {
+            return nil
+        }
+
+        guard let authInfo = kubeConfig.users?.filter({ $0.name == context.user }).map(\.authInfo).first else {
+            return nil
+        }
+
+        guard let authentication = authInfo.authentication(logger: logger) else {
+            return nil
+        }
+
+        return KubernetesClientConfig(
+            masterURL: masterURL,
+            namespace: context.namespace ?? "default",
+            authentication: authentication,
+            trustRoots: cluster.trustRoots(logger: logger),
+            insecureSkipTLSVerify: cluster.insecureSkipTLSVerify ?? true,
+            timeout: timeout,
+            redirectConfiguration: redirectConfiguration
+        )
+    }
+}
+
 // MARK: - URLConfigLoader
 
 internal struct URLConfigLoader: KubernetesClientConfigLoader {