make ConfigMap collector namespace-optional (#1212)

* try to load default namespace from kubectl current context

* use  ns from kubectl context when no ns is given in the spec

* remove test prints

* Update pkg/collect/configmap.go

Co-authored-by: Diamon Wiggins <38189728+diamonwiggins@users.noreply.github.com>

---------

Co-authored-by: Diamon Wiggins <38189728+diamonwiggins@users.noreply.github.com>

pkg/collect/configmap.go

@@ -10,11 +10,13 @@ import (
 
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
+	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
 	corev1 "k8s.io/api/core/v1"
 	kuberneteserrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 type ConfigMapOutput struct {
@@ -49,8 +51,20 @@ func (c *CollectConfigMap) Collect(progressChan chan<- interface{}) (CollectorRe
 	output := NewResult()
 
 	configMaps := []corev1.ConfigMap{}
+	namespace := c.Collector.Namespace
+
 	if c.Collector.Name != "" {
-		configMap, err := c.Client.CoreV1().ConfigMaps(c.Collector.Namespace).Get(c.Context, c.Collector.Name, metav1.GetOptions{})
+		if namespace == "" {
+			kubeconfig := k8sutil.GetKubeconfig()
+			ns, _, err := kubeconfig.Namespace()
+			klog.V(2).Infof("no namespace was set for configmap '%s': using namespace '%s' from current kubeconfig context", c.Collector.Name, ns)
+			if err != nil {
+				return nil, errors.Wrapf(err, "a namespace was not specified for configmap '%s' and could not be discovered from kubeconfig", c.Collector.Name)
+			}
+			namespace = ns
+		}
+		klog.V(1).Infof("looking for configmap '%s' in namespace '%s'", c.Collector.Name, namespace)
+		configMap, err := c.Client.CoreV1().ConfigMaps(namespace).Get(c.Context, c.Collector.Name, metav1.GetOptions{})
 		if err != nil {
 			if kuberneteserrors.IsNotFound(err) {
 				filePath, encoded, err := configMapToOutput(c.Collector, nil, c.Collector.Name)

testdata/supportbundle/configmaps.yaml

@@ -0,0 +1,21 @@
+apiVersion: troubleshoot.sh/v1beta2
+kind: SupportBundle
+metadata:
+  name: example-collect-all-configmap-data
+spec:
+  collectors:
+    - configMap:
+        name: kube-root-ca.crt
+        # expected in default namespace
+    - configMap:
+        name: cluster-info
+        # missing namespace parameter
+    - configMap:
+        name: does-not-exist
+    - configMap:
+        selector:
+          - app=kube-proxy
+        # only selector set
+    - configMap:
+        name: coredns
+        namespace: kube-system