vpc/dhcp_options: Fix panic

.changelog/39427.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_vpc_dhcp_options: Fix a bug causing a panic crash when an option is absent
+```

internal/service/ec2/vpc_dhcp_options.go

@@ -255,27 +255,33 @@ func newDHCPOptionsMap(tfToApi map[string]string) *dhcpOptionsMap {
 
 // dhcpConfigurationsToResourceData sets Terraform ResourceData from a list of AWS API DHCP configurations.
 func (m *dhcpOptionsMap) dhcpConfigurationsToResourceData(dhcpConfigurations []awstypes.DhcpConfiguration, d *schema.ResourceData) error {
- for v := range m.tfToApi {
- d.Set(v, nil)
+ // Clear existing values
+ for tfName := range m.tfToApi {
+ d.Set(tfName, nil)
  }
 
  for _, dhcpConfiguration := range dhcpConfigurations {
  apiName := aws.ToString(dhcpConfiguration.Key)
- if tfName, ok := m.apiToTf[apiName]; ok {
- switch v := d.Get(tfName).(type) {
- case string:
- d.Set(tfName, dhcpConfiguration.Values[0].Value)
- case []interface{}:
- var values []*string
- for _, v := range dhcpConfiguration.Values {
- values = append(values, v.Value)
+ tfName, ok := m.apiToTf[apiName]
+ if !ok {
+ return fmt.Errorf("unsupported DHCP option: %s", apiName)
+ }
+
+ currentValue := d.Get(tfName)
+
+ switch currentValue.(type) {
+ case string:
+ d.Set(tfName, dhcpConfiguration.Values[0].Value)
+ case []interface{}:
+ var values []string
+ for _, v := range dhcpConfiguration.Values {
+ if v.Value != nil {
+ values = append(values, aws.ToString(v.Value))
  }
- d.Set(tfName, values)
- default:
- return fmt.Errorf("Attribute (%s) is of unsupported type: %T", tfName, v)
  }
- } else {
- return fmt.Errorf("Unsupported DHCP option: %s", apiName)
+ d.Set(tfName, values)
+ default:
+ return fmt.Errorf("attribute (%s) is of unsupported type: %T", tfName, currentValue)
  }
  }
 
@@ -287,7 +293,8 @@ func (m *dhcpOptionsMap) resourceDataToDHCPConfigurations(d *schema.ResourceData
  var output []awstypes.NewDhcpConfiguration
 
  for tfName, apiName := range m.tfToApi {
- switch v := d.Get(tfName).(type) {
+ value := d.Get(tfName)
+ switch v := value.(type) {
  case string:
  if v != "" {
  output = append(output, awstypes.NewDhcpConfiguration{
@@ -297,10 +304,9 @@ func (m *dhcpOptionsMap) resourceDataToDHCPConfigurations(d *schema.ResourceData
  }
  case []interface{}:
  var values []string
- for _, v := range v {
- v := v.(string)
- if v != "" {
- values = append(values, v)
+ for _, item := range v {
+ if str, ok := item.(string); ok && str != "" {
+ values = append(values, str)
  }
  }
  if len(values) > 0 {
@@ -310,7 +316,7 @@ func (m *dhcpOptionsMap) resourceDataToDHCPConfigurations(d *schema.ResourceData
  })
  }
  default:
- return nil, fmt.Errorf("Attribute (%s) is of unsupported type: %T", tfName, v)
+ return nil, fmt.Errorf("attribute (%s) is of unsupported type: %T", tfName, value)
  }
  }