1 files changed, 110 insertions, 0 deletions
diff --git a/lib/gitlab/kubernetes/kube_client.rb b/lib/gitlab/kubernetes/kube_client.rb
new file mode 100644
index 00000000000..8312b901524
--- /dev/null
+++ b/lib/gitlab/kubernetes/kube_client.rb
@@ -0,0 +1,110 @@
+# frozen_string_literal: true
+
+require 'uri'
+
+module Gitlab
+  module Kubernetes
+    # Wrapper around Kubeclient::Client to dispatch
+    # the right message to the client that can respond to the message.
+    # We must have a kubeclient for each ApiGroup as there is no
+    # other way to use the Kubeclient gem.
+    #
+    # See https://github.com/abonas/kubeclient/issues/348.
+    class KubeClient
+      include Gitlab::Utils::StrongMemoize
+
+      SUPPORTED_API_GROUPS = [
+        'api',
+        'apis/rbac.authorization.k8s.io',
+        'apis/extensions'
+      ].freeze
+
+      # Core API methods delegates to the core api group client
+      delegate :get_pods,
+        :get_secrets,
+        :get_config_map,
+        :get_namespace,
+        :get_pod,
+        :get_service,
+        :get_service_account,
+        :delete_pod,
+        :create_config_map,
+        :create_namespace,
+        :create_pod,
+        :create_service_account,
+        :update_config_map,
+        :update_service_account,
+        to: :core_client
+
+      # RBAC methods delegates to the apis/rbac.authorization.k8s.io api
+      # group client
+      delegate :create_cluster_role_binding,
+        :get_cluster_role_binding,
+        :update_cluster_role_binding,
+        to: :rbac_client
+
+      # Deployments resource is currently on the apis/extensions api group
+      delegate :get_deployments,
+        to: :extensions_client
+
+      # non-entity methods that can only work with the core client
+      # as it uses the pods/log resource
+      delegate :get_pod_log,
+        :watch_pod_log,
+        to: :core_client
+
+      def initialize(api_prefix, api_groups = ['api'], api_version = 'v1', **kubeclient_options)
+        raise ArgumentError unless check_api_groups_supported?(api_groups)
+
+        @api_prefix = api_prefix
+        @api_groups = api_groups
+        @api_version = api_version
+        @kubeclient_options = kubeclient_options
+      end
+
+      def discover!
+        clients.each(&:discover)
+      end
+
+      def clients
+        hashed_clients.values
+      end
+
+      def core_client
+        hashed_clients['api']
+      end
+
+      def rbac_client
+        hashed_clients['apis/rbac.authorization.k8s.io']
+      end
+
+      def extensions_client
+        hashed_clients['apis/extensions']
+      end
+
+      def hashed_clients
+        strong_memoize(:hashed_clients) do
+          @api_groups.map do |api_group|
+            api_url = join_api_url(@api_prefix, api_group)
+            [api_group, ::Kubeclient::Client.new(api_url, @api_version, **@kubeclient_options)]
+          end.to_h
+        end
+      end
+
+      private
+
+      def check_api_groups_supported?(api_groups)
+        api_groups.all? {|api_group| SUPPORTED_API_GROUPS.include?(api_group) }
+      end
+
+      def join_api_url(api_prefix, api_path)
+        url = URI.parse(api_prefix)
+        prefix = url.path.sub(%r{/+\z}, '')
+
+        url.path = [prefix, api_path].join("/")
+
+        url.to_s
+      end
+    end
+  end
+end