From 823c2988e9634afeb69a5fec3f5cc854236b3948 Mon Sep 17 00:00:00 2001
From: Yu Qi Zhang <jerzhang@redhat.com>
Date: Wed, 8 Apr 2020 11:33:33 -0400
Subject: [PATCH] controller: do not error on empty Ignition configs

With the introduction of rawExtension for Ignition config objects
via https://github.com/openshift/machine-config-operator/pull/996,
we also now use ignition.Parse directly to process the validity of
ignition configs. This will cause machineconfigs without a Ignition
section to fail, which we don't want.

Also modify some error messages for clarity.

Signed-off-by: Yu Qi Zhang <jerzhang@redhat.com>
---
 pkg/controller/common/helpers.go              | 41 +++++++++++++------
 .../container-runtime-config/helpers.go       |  2 +-
 pkg/controller/kubelet-config/helpers.go      |  2 +-
 3 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/pkg/controller/common/helpers.go b/pkg/controller/common/helpers.go
index 75de24d3c5..3455ad1ec9 100644
--- a/pkg/controller/common/helpers.go
+++ b/pkg/controller/common/helpers.go
@@ -28,10 +28,16 @@ func MergeMachineConfigs(configs []*mcfgv1.MachineConfig, osImageURL string) (*m
 
 	var fips bool
 	var kernelType string
+	var outIgn igntypes.Config
 
-	outIgn, report, err := ign.Parse(configs[0].Spec.Config.Raw)
-	if err != nil {
-		return nil, errors.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
+	if configs[0].Spec.Config.Raw == nil {
+		outIgn = igntypes.Config{}
+	} else {
+		parsedIgn, report, err := ign.Parse(configs[0].Spec.Config.Raw)
+		if err != nil {
+			return nil, errors.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
+		}
+		outIgn = parsedIgn
 	}
 
 	for idx := 1; idx < len(configs); idx++ {
@@ -39,9 +45,16 @@ func MergeMachineConfigs(configs []*mcfgv1.MachineConfig, osImageURL string) (*m
 		if configs[idx].Spec.FIPS {
 			fips = true
 		}
-		appendIgn, report, err := ign.Parse(configs[idx].Spec.Config.Raw)
-		if err != nil {
-			return nil, errors.Errorf("parsing appendix Ignition config failed with error: %v\nReport: %v", err, report)
+
+		var appendIgn igntypes.Config
+		if configs[idx].Spec.Config.Raw == nil {
+			appendIgn = igntypes.Config{}
+		} else {
+			parsedIgn, report, err := ign.Parse(configs[idx].Spec.Config.Raw)
+			if err != nil {
+				return nil, errors.Errorf("parsing appendix Ignition config failed with error: %v\nReport: %v", err, report)
+			}
+			appendIgn = parsedIgn
 		}
 		outIgn = ign.Append(outIgn, appendIgn)
 	}
@@ -121,12 +134,16 @@ func ValidateMachineConfig(cfg mcfgv1.MachineConfigSpec) error {
 	if !(cfg.KernelType == "" || cfg.KernelType == KernelTypeDefault || cfg.KernelType == KernelTypeRealtime) {
 		return errors.Errorf("kernelType=%s is invalid", cfg.KernelType)
 	}
-	ignCfg, report, err := ign.Parse(cfg.Config.Raw)
-	if err != nil {
-		return errors.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
-	}
-	if err := ValidateIgnition(ignCfg); err != nil {
-		return err
+
+	if cfg.Config.Raw != nil {
+		ignCfg, report, err := ign.Parse(cfg.Config.Raw)
+		if err != nil {
+			return errors.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
+		}
+		if err := ValidateIgnition(ignCfg); err != nil {
+			return err
+		}
 	}
+
 	return nil
 }
diff --git a/pkg/controller/container-runtime-config/helpers.go b/pkg/controller/container-runtime-config/helpers.go
index 899f8b459e..4c29ebbb25 100644
--- a/pkg/controller/container-runtime-config/helpers.go
+++ b/pkg/controller/container-runtime-config/helpers.go
@@ -138,7 +138,7 @@ func findRegistriesConfig(mc *mcfgv1.MachineConfig) (*igntypes.File, error) {
 func findPolicyJSON(mc *mcfgv1.MachineConfig) (*igntypes.File, error) {
 	ignCfg, report, err := ign.Parse(mc.Spec.Config.Raw)
 	if err != nil {
-		return nil, fmt.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
+		return nil, fmt.Errorf("parsing Policy JSON Ignition config failed with error: %v\nReport: %v", err, report)
 	}
 	for _, c := range ignCfg.Storage.Files {
 		if c.Path == policyConfigPath {
diff --git a/pkg/controller/kubelet-config/helpers.go b/pkg/controller/kubelet-config/helpers.go
index 0efe0c0f24..ccb5c4494c 100644
--- a/pkg/controller/kubelet-config/helpers.go
+++ b/pkg/controller/kubelet-config/helpers.go
@@ -52,7 +52,7 @@ func createNewDefaultFeatureGate() *osev1.FeatureGate {
 func findKubeletConfig(mc *mcfgv1.MachineConfig) (*igntypes.File, error) {
 	ignCfg, report, err := ign.Parse(mc.Spec.Config.Raw)
 	if err != nil {
-		return nil, fmt.Errorf("parsing Ignition config failed with error: %v\nReport: %v", err, report)
+		return nil, fmt.Errorf("parsing Kubelet Ignition config failed with error: %v\nReport: %v", err, report)
 	}
 	for _, c := range ignCfg.Storage.Files {
 		if c.Path == "/etc/kubernetes/kubelet.conf" {