Added support to set builder and fn pod specs via helm chart (#2461)

The users can now set the pod spec for builder and fn pods via helm chart.
Currently we have set some default securitycontext for the pods. Before there were no permissions set and the user would by default enter root when kubectl exec into pod. Now the permissions have been set and the user will not be able to access root directory in poolmgr and newdeploy pods.

pkg/buildermgr/buildermgr.go

@@ -22,11 +22,15 @@ import (
 
 	"github.com/pkg/errors"
 	"go.uber.org/zap"
+	apiv1 "k8s.io/api/core/v1"
 	k8sInformers "k8s.io/client-go/informers"
 
+	fv1 "github.com/fission/fission/pkg/apis/core/v1"
 	"github.com/fission/fission/pkg/crd"
+	"github.com/fission/fission/pkg/executor/util"
 	fetcherConfig "github.com/fission/fission/pkg/fetcher/config"
 	genInformer "github.com/fission/fission/pkg/generated/informers/externalversions"
+	"github.com/fission/fission/pkg/utils"
 )
 
 // Start the buildermgr service.
@@ -48,7 +52,18 @@ func Start(ctx context.Context, logger *zap.Logger, storageSvcUrl string, envBui
 		return errors.Wrap(err, "error making fetcher config")
 	}
 
-	envWatcher := makeEnvironmentWatcher(bmLogger, fissionClient, kubernetesClient, fetcherConfig, envBuilderNamespace)
+	var podSpecPatch *apiv1.PodSpec
+	namespace, err := utils.GetCurrentNamespace()
+	if err != nil {
+		logger.Warn("Current namespace not found %v", zap.Error(err))
+	} else {
+		podSpecPatch, err = util.GetSpecFromConfigMap(ctx, kubernetesClient, fv1.BuilderPodSpecConfigmap, namespace)
+		if err != nil {
+			logger.Warn("Either configmap is not found or error reading data %v", zap.Error(err))
+		}
+	}
+
+	envWatcher := makeEnvironmentWatcher(bmLogger, fissionClient, kubernetesClient, fetcherConfig, envBuilderNamespace, podSpecPatch)
 	go envWatcher.watchEnvironments()
 
 	k8sInformerFactory := k8sInformers.NewSharedInformerFactory(kubernetesClient, time.Minute*30)

pkg/buildermgr/envwatcher.go

@@ -87,6 +87,7 @@ type (
 		fetcherConfig          *fetcherConfig.Config
 		builderImagePullPolicy apiv1.PullPolicy
 		useIstio               bool
+		podSpecPatch           *apiv1.PodSpec
 	}
 )
 
@@ -95,7 +96,8 @@ func makeEnvironmentWatcher(
 	fissionClient versioned.Interface,
 	kubernetesClient kubernetes.Interface,
 	fetcherConfig *fetcherConfig.Config,
-	builderNamespace string) *environmentWatcher {
+	builderNamespace string,
+	podSpecPatch *apiv1.PodSpec) *environmentWatcher {
 
 	useIstio := false
 	enableIstio := os.Getenv("ENABLE_ISTIO")
@@ -119,6 +121,7 @@ func makeEnvironmentWatcher(
 		builderImagePullPolicy: builderImagePullPolicy,
 		useIstio:               useIstio,
 		fetcherConfig:          fetcherConfig,
+		podSpecPatch:           podSpecPatch,
 	}
 
 	go envWatcher.service()
@@ -503,6 +506,16 @@ func (envw *environmentWatcher) createBuilderDeployment(env *fv1.Environment, ns
 		},
 	}
 
+	if envw.podSpecPatch != nil {
+
+		updatedPodSpec, err := util.MergePodSpec(&pod.Spec, envw.podSpecPatch)
+		if err == nil {
+			pod.Spec = *updatedPodSpec
+		} else {
+			envw.logger.Warn("Failed to merge the specs: %v", zap.Error(err))
+		}
+	}
+
 	pod.Spec = *(util.ApplyImagePullSecret(env.Spec.ImagePullSecret, pod.Spec))
 
 	deployment := &appsv1.Deployment{