Fix: Handle nil deployment outputs gracefully

Signed-off-by: Arun P Nair <[email protected]>

Author: arunpnair

pkg/arm/templates/arm.go

@@ -462,6 +462,10 @@ func (d *deployer) pollUntilComplete(
 func getOutputs(
 	deployment *resourcesSDK.DeploymentExtended,
 ) (map[string]interface{}, error) {
+	// Check if deployment output is nil as "outputs" section/element is optional in ARM template.
+	if deployment.Properties.Outputs == nil {
+		return map[string]interface{}{}, nil
+	}
 	outputs, ok := deployment.Properties.Outputs.(map[string]interface{})
 	if !ok {
 		return nil, errors.New("error decoding deployment outputs")

pkg/arm/templates/arm_test.go

@@ -0,0 +1,52 @@
+package templates
+
+import (
+	"testing"
+
+	resourcesSDK "github.com/Azure/azure-sdk-for-go/services/resources/mgmt/2017-05-10/resources"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetOutputs_ValidOutputs(t *testing.T) {
+	deployment := &resourcesSDK.DeploymentExtended{
+		Properties: &resourcesSDK.DeploymentPropertiesExtended{
+			Outputs: map[string]interface{}{
+				"output1": map[string]interface{}{
+					"value": "amaterasu",
+				},
+				"output2": map[string]interface{}{
+					"value": 108,
+				},
+			},
+		},
+	}
+
+	outputs, err := getOutputs(deployment)
+	assert.NoError(t, err)
+	assert.Equal(t, "amaterasu", outputs["output1"])
+	assert.Equal(t, 108, outputs["output2"])
+}
+
+func TestGetOutputs_InvalidOutputs(t *testing.T) {
+	deployment := &resourcesSDK.DeploymentExtended{
+		Properties: &resourcesSDK.DeploymentPropertiesExtended{
+			Outputs: "invalid",
+		},
+	}
+
+	outputs, err := getOutputs(deployment)
+	assert.Error(t, err)
+	assert.Nil(t, outputs)
+}
+
+func TestGetOutputs_NoOutputs(t *testing.T) {
+	deployment := &resourcesSDK.DeploymentExtended{
+		Properties: &resourcesSDK.DeploymentPropertiesExtended{
+			Outputs: nil,
+		},
+	}
+
+	outputs, err := getOutputs(deployment)
+	assert.NoError(t, err)
+	assert.Empty(t, outputs)
+}