From 0849a0acb6093c94a3fb6f22781101427fecfd11 Mon Sep 17 00:00:00 2001
From: Ferdinando Formica <ferdinando.formica@ie.ibm.com>
Date: Thu, 28 Nov 2024 13:59:25 +0000
Subject: [PATCH] #334: protect against empty answers

---
 ns1/resource_record.go      | 96 ++++++++++++++++++++-----------------
 ns1/resource_record_test.go | 17 +++++++
 2 files changed, 68 insertions(+), 45 deletions(-)

diff --git a/ns1/resource_record.go b/ns1/resource_record.go
index 2376c78..540071e 100644
--- a/ns1/resource_record.go
+++ b/ns1/resource_record.go
@@ -370,47 +370,51 @@ func resourceDataToRecord(r *dns.Record, d *schema.ResourceData) error {
 
 	if shortAnswers := d.Get("short_answers").([]interface{}); len(shortAnswers) > 0 {
 		for _, answerRaw := range shortAnswers {
-			answer := answerRaw.(string)
-			switch d.Get("type") {
-			case "TXT", "SPF":
-				r.AddAnswer(dns.NewTXTAnswer(answer))
-			case "CAA":
-				r.AddAnswer(dns.NewAnswer(strings.SplitN(answer, " ", 3)))
-			default:
-				r.AddAnswer(dns.NewAnswer(strings.Split(answer, " ")))
+			if answerRaw != nil {
+				answer := answerRaw.(string)
+				switch d.Get("type") {
+				case "TXT", "SPF":
+					r.AddAnswer(dns.NewTXTAnswer(answer))
+				case "CAA":
+					r.AddAnswer(dns.NewAnswer(strings.SplitN(answer, " ", 3)))
+				default:
+					r.AddAnswer(dns.NewAnswer(strings.Split(answer, " ")))
+				}
 			}
 		}
 	}
 	if answers := d.Get("answers").([]interface{}); len(answers) > 0 {
 		for _, answerRaw := range answers {
-			answer := answerRaw.(map[string]interface{})
-			var a *dns.Answer
-
-			v := answer["answer"].(string)
-			switch d.Get("type") {
-			case "TXT", "SPF":
-				a = dns.NewTXTAnswer(v)
-			case "CAA":
-				a = dns.NewAnswer(strings.SplitN(v, " ", 3))
-			default:
-				a = dns.NewAnswer(strings.Split(v, " "))
-			}
+			if answerRaw != nil {
+				answer := answerRaw.(map[string]interface{})
+				var a *dns.Answer
+
+				v := answer["answer"].(string)
+				switch d.Get("type") {
+				case "TXT", "SPF":
+					a = dns.NewTXTAnswer(v)
+				case "CAA":
+					a = dns.NewAnswer(strings.SplitN(v, " ", 3))
+				default:
+					a = dns.NewAnswer(strings.Split(v, " "))
+				}
 
-			if v, ok := answer["region"]; ok {
-				a.RegionName = v.(string)
-			}
+				if v, ok := answer["region"]; ok {
+					a.RegionName = v.(string)
+				}
 
-			if v, ok := answer["meta"]; ok {
-				log.Println("answer meta", v)
-				meta, err := metaHandler(v)
-				if err != nil {
-					return err
+				if v, ok := answer["meta"]; ok {
+					log.Println("answer meta", v)
+					meta, err := metaHandler(v)
+					if err != nil {
+						return err
+					}
+
+					a.Meta = meta
 				}
 
-				a.Meta = meta
+				r.AddAnswer(a)
 			}
-
-			r.AddAnswer(a)
 		}
 	}
 	log.Println("number of answers found:", len(r.Answers))
@@ -447,21 +451,23 @@ func resourceDataToRecord(r *dns.Record, d *schema.ResourceData) error {
 	r.UseClientSubnet = &useClientSubnet
 
 	if rawFilters := d.Get("filters").([]interface{}); len(rawFilters) > 0 {
-		filters := make([]*filter.Filter, len(rawFilters))
-		for i, filterRaw := range rawFilters {
-			fi := filterRaw.(map[string]interface{})
-			config := make(map[string]interface{})
-			f := filter.Filter{
-				Type:   fi["filter"].(string),
-				Config: config,
-			}
-			if disabled, ok := fi["disabled"]; ok {
-				f.Disabled = disabled.(bool)
-			}
-			if rawConfig, ok := fi["config"]; ok {
-				f.Config = rawConfig.(map[string]interface{})
+		filters := make([]*filter.Filter, 0, len(rawFilters))
+		for _, filterRaw := range rawFilters {
+			if filterRaw != nil {
+				fi := filterRaw.(map[string]interface{})
+				config := make(map[string]interface{})
+				f := filter.Filter{
+					Type:   fi["filter"].(string),
+					Config: config,
+				}
+				if disabled, ok := fi["disabled"]; ok {
+					f.Disabled = disabled.(bool)
+				}
+				if rawConfig, ok := fi["config"]; ok {
+					f.Config = rawConfig.(map[string]interface{})
+				}
+				filters = append(filters, &f)
 			}
-			filters[i] = &f
 		}
 		r.Filters = filters
 	}
diff --git a/ns1/resource_record_test.go b/ns1/resource_record_test.go
index 866d9cd..ba8076e 100644
--- a/ns1/resource_record_test.go
+++ b/ns1/resource_record_test.go
@@ -606,6 +606,10 @@ func TestAccRecord_validationError(t *testing.T) {
 				*/
 				ExpectError: regexp.MustCompile(`(?s)(Error: (zone|domain) has an invalid (leading|trailing) "\.", got: .*){4}`),
 			},
+			{
+				Config:      testAccRecordNoAnswers(rString),
+				ExpectError: regexp.MustCompile(`Invalid body`),
+			},
 		},
 	})
 }
@@ -2018,6 +2022,19 @@ resource "ns1_record" "it" {
 `, rString, rString)
 }
 
+// there must be at least one answer
+func testAccRecordNoAnswers(rString string) string {
+	return fmt.Sprintf(`
+resource "ns1_record" "it" {
+  zone              = "terraform-test-%s.io"
+  domain            = "test.terraform-test-%s.io"
+  type              = "CNAME"
+  ttl               = 60
+  answers {}
+}
+`, rString, rString)
+}
+
 func testAccRecordLink(rString string) string {
 	return fmt.Sprintf(`
 # the name being tested that is a link