fix: network-instance configured DNS servers are not sent to Zedcloud(CI-574) (#145)

The issue was that the configured DNS servers were not sent to the network instances' create request.

Changes:

Fixed the dns field in the dhcp_server schema.
Updated tests to test the dns field.

Author: ikurakin-zededa

v2/resources/testdata/network_instance/create_complete.tf

@@ -140,6 +140,15 @@ resource "zedcloud_network_instance" "complete" {
         }
         mask = "255.255.255.0"
         ntp = "10.1.0.2"
+        dns = [
+          "9.9.9.9",
+          "8.8.8.8",
+          "7.7.7.7",
+          "6.6.6.6",
+          "5.5.5.5",
+          "4.4.4.4",
+          "3.3.3.3"
+        ]
     }
     opaque {
         oconfig = "Test OConfig"

v2/resources/testdata/network_instance/create_complete_expected.yaml

@@ -18,7 +18,14 @@ ip:
     dhcprange:
         end: "10.0.20.100"
         start: "10.0.20.50"
-    dns: []
+    dns:
+        - "9.9.9.9"
+        - "8.8.8.8"
+        - "7.7.7.7"
+        - "6.6.6.6"
+        - "5.5.5.5"
+        - "4.4.4.4"
+        - "3.3.3.3"
     mask: "255.255.255.0"
     ntp: "10.1.0.2"
 kind: NETWORK_INSTANCE_KIND_LOCAL

v2/schemas/dhcp_server.go

@@ -19,7 +19,7 @@ func DHCPServerModel(d *schema.ResourceData) *models.DhcpServerConfig {
 	if dnsIsSet {
 		dnsSlice := dnsInterface.([]interface{})
 		for _, i := range dnsSlice {
-			dnsSlice = append(dnsSlice, i.(string))
+			dns = append(dns, i.(string))
 		}
 	}
 	domain, _ := d.Get("domain").(string)
@@ -53,7 +53,7 @@ func DHCPServerModelFromMap(m map[string]interface{}) *models.DhcpServerConfig {
 	if dnsIsSet {
 		dnsSlice := dnsInterface.([]interface{})
 		for _, i := range dnsSlice {
-			dnsSlice = append(dnsSlice, i.(string))
+			dns = append(dns, i.(string))
 		}
 	}
 	domain, _ := m["domain"].(string)
@@ -117,8 +117,7 @@ func DHCPServer() map[string]*schema.Schema {
 			Elem: &schema.Schema{
 				Type: schema.TypeString,
 			},
-			DiffSuppressFunc: diffSuppressDNSListOrder("dns"),
-			Optional:         true,
+			Optional: true,
 		},
 
 		"domain": {