Allow using custom https.Agent instance (#5564)

* Allow using custom https.Agent instance

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>

* Use .constructor(agentOptions)

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>

* Revert

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>

src/common/k8s-api/kube-api.ts

@@ -169,6 +169,13 @@ export interface IRemoteKubeApiConfig {
     clientCertificateData?: string;
     clientKeyData?: string;
   };
+  /**
+   * Custom instance of https.agent to use for the requests
+   * 
+   * @remarks the custom agent replaced default agent, options skipTLSVerify,
+   * clientCertificateData, clientKeyData and caData are ignored.
+   */
+   agent?: Agent;
 }
 
 export function forCluster<
@@ -240,6 +247,10 @@ export function forRemoteCluster<
     reqInit.agent = new Agent(agentOptions);
   }
 
+  if (config.agent) {
+    reqInit.agent = config.agent;
+  }
+
   const token = config.user.token;
   const request = new KubeJsonApi({
     serverAddress: config.cluster.server,