docs/resources/server_reverse_name.md

@@ -0,0 +1,48 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "binarylane_server_reverse_name Resource - terraform-provider-binarylane"
+subcategory: ""
+description: |-
+  Manage the reverse name (PTR record) for a public IPv4 address of a BinaryLane server. Destroying this resource clears the custom reverse name, restoring the BinaryLane default.
+---
+
+# binarylane_server_reverse_name (Resource)
+
+Manage the reverse name (PTR record) for a public IPv4 address of a BinaryLane server. Destroying this resource clears the custom reverse name, restoring the BinaryLane default.
+
+## Example Usage
+
+```terraform
+resource "binarylane_server" "example" {
+  # ...
+}
+
+resource "binarylane_server_reverse_name" "example" {
+  server_id    = binarylane_server.example.id
+  ipv4_address = binarylane_server.example.public_ipv4_addresses.0
+  reverse_name = "mx1.example.com"
+}
+```
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `ipv4_address` (String) The public IPv4 address to set the reverse name for.
+- `reverse_name` (String) The reverse name (PTR record) for the IPv4 address.
+- `server_id` (Number) The ID of the server the IPv4 address is assigned to.
+
+### Read-Only
+
+- `id` (String) The ID of this resource, in the format `<server_id>:<ipv4_address>`.
+
+## Import
+
+Import is supported using the following syntax:
+
+The [`terraform import` command](https://developer.hashicorp.com/terraform/cli/commands/import) can be used, for example:
+
+```shell
+terraform import binarylane_server_reverse_name.example "<server id>:<ipv4 address>"
+```

examples/resources/binarylane_server_reverse_name/import.sh

@@ -0,0 +1 @@
+terraform import binarylane_server_reverse_name.example "<server id>:<ipv4 address>"

examples/resources/binarylane_server_reverse_name/resource.tf

@@ -0,0 +1,9 @@
+resource "binarylane_server" "example" {
+  # ...
+}
+
+resource "binarylane_server_reverse_name" "example" {
+  server_id    = binarylane_server.example.id
+  ipv4_address = binarylane_server.example.public_ipv4_addresses.0
+  reverse_name = "mx1.example.com"
+}

internal/provider/provider.go

@@ -103,6 +103,7 @@ func (p *binarylaneProvider) Resources(_ context.Context) []func() resource.Reso
 	return []func() resource.Resource{
 		NewServerResource,
 		NewServerFirewallRulesResource,
+		NewServerReverseNameResource,
 		NewSshKeyResource,
 		NewVpcResource,
 		NewVpcRouteEntriesResource,

internal/provider/server_firewall_rules_resource.go

@@ -121,6 +121,11 @@ func (r *serverFirewallRulesResource) Create(ctx context.Context, req resource.C
 		return
 	}
 
+	resp.Diagnostics.Append(resolveUnknownDestinationPorts(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
 	// Save data into Terraform state
 	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
 }
@@ -207,6 +212,11 @@ func (r *serverFirewallRulesResource) Update(ctx context.Context, req resource.U
 		return
 	}
 
+	resp.Diagnostics.Append(resolveUnknownDestinationPorts(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
 	// Save updated data into Terraform state
 	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
 }
@@ -245,6 +255,22 @@ func (r *serverFirewallRulesResource) Delete(ctx context.Context, req resource.D
 	}
 }
 
+// Omitted destination_ports (all ports) are planned as unknown because the attribute is computed.
+func resolveUnknownDestinationPorts(ctx context.Context, data *serverFirewallRulesResourceModel) diag.Diagnostics {
+	var rules []resources.FirewallRulesValue
+	diags := data.FirewallRules.ElementsAs(ctx, &rules, false)
+	if diags.HasError() {
+		return diags
+	}
+	for i := range rules {
+		if rules[i].DestinationPorts.IsUnknown() {
+			rules[i].DestinationPorts = types.ListNull(types.StringType)
+		}
+	}
+	data.FirewallRules, diags = types.ListValueFrom(ctx, resources.FirewallRulesValue{}.Type(ctx), rules)
+	return diags
+}
+
 func GetFirewallRulesState(ctx context.Context, firewallRules *[]binarylane.AdvancedFirewallRule) (basetypes.ListValue, diag.Diagnostics) {
 	var diags diag.Diagnostics
 
@@ -258,7 +284,7 @@ func GetFirewallRulesState(ctx context.Context, firewallRules *[]binarylane.Adva
 			destinationAddresses, diag := types.ListValueFrom(ctx, types.StringType, rule.DestinationAddresses)
 			diags.Append(diag...)
 
-			var destinationPorts basetypes.ListValue
+			destinationPorts := types.ListNull(types.StringType)
 			if rule.DestinationPorts != nil {
 				destinationPorts, diag = types.ListValueFrom(ctx, types.StringType, rule.DestinationPorts)
 				diags.Append(diag...)

internal/provider/server_firewall_rules_resource_unit_test.go

@@ -0,0 +1,94 @@
+package provider
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"terraform-provider-binarylane/internal/binarylane"
+	"terraform-provider-binarylane/internal/resources"
+
+	"github.com/hashicorp/terraform-plugin-framework/attr"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/resource"
+	"github.com/hashicorp/terraform-plugin-framework/tfsdk"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+func TestServerFirewallRulesResourceOmittedPorts(t *testing.T) {
+	ctx := context.Background()
+
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		if r.Method == http.MethodGet {
+			_, _ = w.Write([]byte(`{"firewall_rules":[{"action":"accept","protocol":"icmp","source_addresses":["10.0.0.0/8"],"destination_addresses":["10.0.0.1"],"destination_ports":null}]}`))
+			return
+		}
+		_, _ = w.Write([]byte(`{}`))
+	}))
+	defer srv.Close()
+
+	client, err := binarylane.NewClientWithConfig(srv.URL, "test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	r := &serverFirewallRulesResource{bc: &BinarylaneClient{client: client}}
+
+	schemaResp := resource.SchemaResponse{}
+	r.Schema(ctx, resource.SchemaRequest{}, &schemaResp)
+	s := schemaResp.Schema
+	emptyState := func() tfsdk.State {
+		return tfsdk.State{Schema: s, Raw: tftypes.NewValue(s.Type().TerraformType(ctx), nil)}
+	}
+
+	ruleType := resources.FirewallRulesValue{}
+	rule := resources.NewFirewallRulesValueMust(ruleType.AttributeTypes(ctx), map[string]attr.Value{
+		"description":           types.StringNull(),
+		"action":                types.StringValue("accept"),
+		"protocol":              types.StringValue("icmp"),
+		"destination_addresses": types.ListValueMust(types.StringType, []attr.Value{types.StringValue("10.0.0.1")}),
+		"destination_ports":     types.ListUnknown(types.StringType),
+		"source_addresses":      types.ListValueMust(types.StringType, []attr.Value{types.StringValue("10.0.0.0/8")}),
+	})
+	model := serverFirewallRulesResourceModel{}
+	model.ServerId = types.Int64Value(1)
+	model.FirewallRules = types.ListValueMust(ruleType.Type(ctx), []attr.Value{rule})
+
+	plan := tfsdk.Plan{Schema: s, Raw: tftypes.NewValue(s.Type().TerraformType(ctx), nil)}
+	if diags := plan.Set(ctx, &model); diags.HasError() {
+		t.Fatal(diags)
+	}
+
+	createResp := resource.CreateResponse{State: emptyState()}
+	r.Create(ctx, resource.CreateRequest{Plan: plan}, &createResp)
+	if createResp.Diagnostics.HasError() {
+		t.Fatal(createResp.Diagnostics)
+	}
+	var ports types.List
+	createResp.State.GetAttribute(ctx, path.Root("firewall_rules").AtListIndex(0).AtName("destination_ports"), &ports)
+	if !ports.IsNull() {
+		t.Fatalf("create: expected null destination_ports, got %s", ports)
+	}
+
+	updateResp := resource.UpdateResponse{State: emptyState()}
+	r.Update(ctx, resource.UpdateRequest{Plan: plan}, &updateResp)
+	if updateResp.Diagnostics.HasError() {
+		t.Fatal(updateResp.Diagnostics)
+	}
+	updateResp.State.GetAttribute(ctx, path.Root("firewall_rules").AtListIndex(0).AtName("destination_ports"), &ports)
+	if !ports.IsNull() {
+		t.Fatalf("update: expected null destination_ports, got %s", ports)
+	}
+
+	readResp := resource.ReadResponse{State: createResp.State}
+	r.Read(ctx, resource.ReadRequest{State: createResp.State}, &readResp)
+	if readResp.Diagnostics.HasError() {
+		t.Fatal(readResp.Diagnostics)
+	}
+	readResp.State.GetAttribute(ctx, path.Root("firewall_rules").AtListIndex(0).AtName("destination_ports"), &ports)
+	if !ports.IsNull() {
+		t.Fatalf("read: expected null destination_ports, got %s", ports)
+	}
+}

internal/provider/server_reverse_name_resource.go

@@ -0,0 +1,296 @@
+package provider
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/netip"
+	"strconv"
+	"strings"
+	"terraform-provider-binarylane/internal/binarylane"
+
+	"github.com/hashicorp/terraform-plugin-framework-validators/int64validator"
+	"github.com/hashicorp/terraform-plugin-framework-validators/stringvalidator"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/resource"
+	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
+	"github.com/hashicorp/terraform-plugin-framework/resource/schema/int64planmodifier"
+	"github.com/hashicorp/terraform-plugin-framework/resource/schema/planmodifier"
+	"github.com/hashicorp/terraform-plugin-framework/resource/schema/stringplanmodifier"
+	"github.com/hashicorp/terraform-plugin-framework/schema/validator"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-log/tflog"
+)
+
+var (
+	_ resource.Resource                = &serverReverseNameResource{}
+	_ resource.ResourceWithConfigure   = &serverReverseNameResource{}
+	_ resource.ResourceWithImportState = &serverReverseNameResource{}
+)
+
+func NewServerReverseNameResource() resource.Resource {
+	return &serverReverseNameResource{}
+}
+
+type serverReverseNameResource struct {
+	bc *BinarylaneClient
+}
+
+type serverReverseNameResourceModel struct {
+	Id          types.String `tfsdk:"id"`
+	ServerId    types.Int64  `tfsdk:"server_id"`
+	Ipv4Address types.String `tfsdk:"ipv4_address"`
+	ReverseName types.String `tfsdk:"reverse_name"`
+}
+
+func (r *serverReverseNameResource) Configure(_ context.Context, req resource.ConfigureRequest, resp *resource.ConfigureResponse) {
+	if req.ProviderData == nil {
+		return
+	}
+	bc, ok := req.ProviderData.(BinarylaneClient)
+	if !ok {
+		resp.Diagnostics.AddError(
+			"Unexpected Resource Configure Type",
+			fmt.Sprintf("Expected *BinarylaneClient, got: %T.", req.ProviderData),
+		)
+		return
+	}
+	r.bc = &bc
+}
+
+func (r *serverReverseNameResource) Metadata(ctx context.Context, req resource.MetadataRequest, resp *resource.MetadataResponse) {
+	resp.TypeName = req.ProviderTypeName + "_server_reverse_name"
+}
+
+func (r *serverReverseNameResource) Schema(ctx context.Context, req resource.SchemaRequest, resp *resource.SchemaResponse) {
+	resp.Schema = schema.Schema{
+		Description: "Manage the reverse name (PTR record) for a public IPv4 address of a BinaryLane server. " +
+			"Destroying this resource clears the custom reverse name, restoring the BinaryLane default.",
+		Attributes: map[string]schema.Attribute{
+			"id": schema.StringAttribute{
+				Description: "The ID of this resource, in the format `<server_id>:<ipv4_address>`.",
+				Computed:    true,
+				PlanModifiers: []planmodifier.String{
+					stringplanmodifier.UseStateForUnknown(),
+				},
+			},
+			"server_id": schema.Int64Attribute{
+				Description: "The ID of the server the IPv4 address is assigned to.",
+				Required:    true,
+				Validators: []validator.Int64{
+					int64validator.AtLeast(1),
+				},
+				PlanModifiers: []planmodifier.Int64{
+					int64planmodifier.RequiresReplace(),
+				},
+			},
+			"ipv4_address": schema.StringAttribute{
+				Description: "The public IPv4 address to set the reverse name for.",
+				Required:    true,
+				PlanModifiers: []planmodifier.String{
+					stringplanmodifier.RequiresReplace(),
+				},
+			},
+			"reverse_name": schema.StringAttribute{
+				Description: "The reverse name (PTR record) for the IPv4 address.",
+				Required:    true,
+				Validators: []validator.String{
+					stringvalidator.LengthAtLeast(1),
+				},
+			},
+		},
+	}
+}
+
+func (r *serverReverseNameResource) Create(ctx context.Context, req resource.CreateRequest, resp *resource.CreateResponse) {
+	var data serverReverseNameResourceModel
+
+	// Read Terraform plan data into the model
+	resp.Diagnostics.Append(req.Plan.Get(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	// Create API call logic
+	tflog.Debug(ctx, fmt.Sprintf("Creating server reverse name: server_id=%d, ipv4_address=%s",
+		data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+	err := r.changeReverseName(ctx, data.ServerId.ValueInt64(), data.Ipv4Address.ValueString(), data.ReverseName.ValueStringPointer())
+	if err != nil {
+		resp.Diagnostics.AddError(
+			fmt.Sprintf("Error creating server reverse name: server_id=%d, ipv4_address=%s", data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()),
+			err.Error(),
+		)
+		return
+	}
+
+	data.Id = types.StringValue(formatServerReverseNameId(data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+
+	// Save data into Terraform state
+	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
+}
+
+func (r *serverReverseNameResource) Read(ctx context.Context, req resource.ReadRequest, resp *resource.ReadResponse) {
+	var data serverReverseNameResourceModel
+
+	// Read Terraform prior state data into the model
+	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	// Read API call logic
+	tflog.Debug(ctx, fmt.Sprintf("Reading server reverse name: server_id=%d, ipv4_address=%s",
+		data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+	serverResp, err := r.bc.client.GetServersServerIdWithResponse(ctx, data.ServerId.ValueInt64())
+	if err != nil {
+		resp.Diagnostics.AddError(
+			fmt.Sprintf("Error reading server reverse name: server_id=%d", data.ServerId.ValueInt64()),
+			err.Error(),
+		)
+		return
+	}
+	if serverResp.StatusCode() == http.StatusNotFound {
+		tflog.Warn(ctx, fmt.Sprintf("Server not found, removing reverse name from state: server_id=%d", data.ServerId.ValueInt64()))
+		resp.State.RemoveResource(ctx)
+		return
+	}
+	if serverResp.StatusCode() != http.StatusOK {
+		resp.Diagnostics.AddError(
+			"Unexpected HTTP status code reading server reverse name",
+			fmt.Sprintf("Received %s reading server reverse name: server_id=%d. Details: %s", serverResp.Status(), data.ServerId.ValueInt64(), serverResp.Body))
+		return
+	}
+
+	var network *binarylane.Network
+	for i, n := range serverResp.JSON200.Server.Networks.V4 {
+		if n.IpAddress == data.Ipv4Address.ValueString() {
+			network = &serverResp.JSON200.Server.Networks.V4[i]
+			break
+		}
+	}
+	if network == nil {
+		tflog.Warn(ctx, fmt.Sprintf("IPv4 address not found on server, removing reverse name from state: server_id=%d, ipv4_address=%s",
+			data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+		resp.State.RemoveResource(ctx)
+		return
+	}
+
+	data.Id = types.StringValue(formatServerReverseNameId(data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+	data.ReverseName = types.StringPointerValue(network.ReverseName)
+
+	// Save into Terraform state
+	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
+}
+
+func (r *serverReverseNameResource) Update(ctx context.Context, req resource.UpdateRequest, resp *resource.UpdateResponse) {
+	var data serverReverseNameResourceModel
+
+	// Read Terraform plan data into the model
+	resp.Diagnostics.Append(req.Plan.Get(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	// Update API call logic
+	tflog.Debug(ctx, fmt.Sprintf("Updating server reverse name: server_id=%d, ipv4_address=%s",
+		data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+	err := r.changeReverseName(ctx, data.ServerId.ValueInt64(), data.Ipv4Address.ValueString(), data.ReverseName.ValueStringPointer())
+	if err != nil {
+		resp.Diagnostics.AddError(
+			fmt.Sprintf("Error updating server reverse name: server_id=%d, ipv4_address=%s", data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()),
+			err.Error(),
+		)
+		return
+	}
+
+	// Save updated data into Terraform state
+	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
+}
+
+func (r *serverReverseNameResource) Delete(ctx context.Context, req resource.DeleteRequest, resp *resource.DeleteResponse) {
+	var data serverReverseNameResourceModel
+
+	// Read Terraform prior state data into the model
+	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	// Delete API call logic: a null reverse name clears the custom reverse name
+	tflog.Debug(ctx, fmt.Sprintf("Deleting server reverse name: server_id=%d, ipv4_address=%s",
+		data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()))
+	err := r.changeReverseName(ctx, data.ServerId.ValueInt64(), data.Ipv4Address.ValueString(), nil)
+	if err != nil {
+		resp.Diagnostics.AddError(
+			fmt.Sprintf("Error deleting server reverse name: server_id=%d, ipv4_address=%s", data.ServerId.ValueInt64(), data.Ipv4Address.ValueString()),
+			err.Error(),
+		)
+		return
+	}
+}
+
+func (r *serverReverseNameResource) ImportState(
+	ctx context.Context, req resource.ImportStateRequest, resp *resource.ImportStateResponse,
+) {
+	serverId, ipv4Address, err := parseServerReverseNameId(req.ID)
+	if err != nil {
+		resp.Diagnostics.AddError(
+			"Error importing server reverse name",
+			"Could not import server reverse name, unexpected error (ID should be <server_id>:<ipv4_address>): "+err.Error(),
+		)
+		return
+	}
+
+	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("id"), req.ID)...)
+	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("server_id"), serverId)...)
+	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("ipv4_address"), ipv4Address)...)
+}
+
+func (r *serverReverseNameResource) changeReverseName(ctx context.Context, serverId int64, ipv4Address string, reverseName *string) error {
+	actionResp, err := r.bc.client.PostServersServerIdActionsChangeReverseNameWithResponse(
+		ctx,
+		serverId,
+		binarylane.PostServersServerIdActionsChangeReverseNameJSONRequestBody{
+			Type:        "change_reverse_name",
+			Ipv4Address: ipv4Address,
+			ReverseName: reverseName,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("error changing reverse name for server: server_id=%d, error: %w", serverId, err)
+	}
+	if actionResp.StatusCode() != http.StatusOK && actionResp.StatusCode() != http.StatusAccepted {
+		return fmt.Errorf("unexpected HTTP status code changing reverse name for server: server_id=%d, details: %s", serverId, actionResp.Body)
+	}
+	// 202 Accepted carries no action ID to poll
+	if actionResp.JSON200 == nil {
+		return nil
+	}
+
+	sr := serverResource{bc: r.bc}
+	if err := sr.waitForServerAction(ctx, serverId, actionResp.JSON200.Action.Id); err != nil {
+		return fmt.Errorf("error changing reverse name: %w", err)
+	}
+
+	return nil
+}
+
+func formatServerReverseNameId(serverId int64, ipv4Address string) string {
+	return fmt.Sprintf("%d:%s", serverId, ipv4Address)
+}
+
+func parseServerReverseNameId(id string) (int64, string, error) {
+	serverIdStr, ipv4Address, ok := strings.Cut(id, ":")
+	if !ok {
+		return 0, "", fmt.Errorf("missing ':' separator in %q", id)
+	}
+	serverId, err := strconv.ParseInt(serverIdStr, 10, 64)
+	if err != nil || serverId < 1 {
+		return 0, "", fmt.Errorf("invalid server_id %q", serverIdStr)
+	}
+	addr, err := netip.ParseAddr(ipv4Address)
+	if err != nil || !addr.Is4() {
+		return 0, "", fmt.Errorf("invalid ipv4_address %q", ipv4Address)
+	}
+	return serverId, ipv4Address, nil
+}

internal/provider/server_reverse_name_resource_test.go

@@ -0,0 +1,148 @@
+package provider
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"strconv"
+	"testing"
+
+	"terraform-provider-binarylane/internal/binarylane"
+
+	"github.com/hashicorp/terraform-plugin-testing/helper/resource"
+	"github.com/hashicorp/terraform-plugin-testing/terraform"
+)
+
+func TestParseServerReverseNameId(t *testing.T) {
+	serverId, ip, err := parseServerReverseNameId(formatServerReverseNameId(12345, "203.0.113.7"))
+	if err != nil || serverId != 12345 || ip != "203.0.113.7" {
+		t.Fatalf("round trip: got (%d, %q, %v)", serverId, ip, err)
+	}
+
+	for _, id := range []string{
+		"",
+		"12345",
+		"12345:",
+		":203.0.113.7",
+		"abc:203.0.113.7",
+		"0:203.0.113.7",
+		"-1:203.0.113.7",
+		"12345:not-an-ip",
+		"12345:2001:db8::1",
+		"12345:203.0.113.7:80",
+	} {
+		if _, _, err := parseServerReverseNameId(id); err == nil {
+			t.Errorf("expected error parsing %q", id)
+		}
+	}
+}
+
+func TestServerReverseNameResource(t *testing.T) {
+	// Must assign a password to the server or Binary Lane will send emails
+	password := GenerateTestPassword(t)
+
+	serverConfig := `
+
+resource "binarylane_server" "test" {
+  name              = "tf-test-server-reverse-name"
+  region            = "per"
+  image             = "debian-12"
+  size              = "std-min"
+  password          = "` + password + `"
+  public_ipv4_count = 1
+}
+`
+
+	var serverId int64
+	var ipv4Address string
+
+	resource.ParallelTest(t, resource.TestCase{
+		ProtoV6ProviderFactories: testAccProtoV6ProviderFactories,
+		CheckDestroy: func(_ *terraform.State) error {
+			return testAccCheckServerReverseNameCleared(serverId, ipv4Address)
+		},
+		Steps: []resource.TestStep{
+			// Create and Read testing
+			{
+				Config: providerConfig + serverConfig + `
+resource "binarylane_server_reverse_name" "test" {
+  server_id    = binarylane_server.test.id
+  ipv4_address = binarylane_server.test.public_ipv4_addresses.0
+  reverse_name = "tf-test-ptr.example.com"
+}
+`,
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttrPair("binarylane_server_reverse_name.test", "server_id", "binarylane_server.test", "id"),
+					resource.TestCheckResourceAttrPair("binarylane_server_reverse_name.test", "ipv4_address", "binarylane_server.test", "public_ipv4_addresses.0"),
+					resource.TestCheckResourceAttr("binarylane_server_reverse_name.test", "reverse_name", "tf-test-ptr.example.com"),
+					resource.TestCheckResourceAttrSet("binarylane_server_reverse_name.test", "id"),
+					func(s *terraform.State) error {
+						attrs := s.RootModule().Resources["binarylane_server_reverse_name.test"].Primary.Attributes
+						var err error
+						serverId, err = strconv.ParseInt(attrs["server_id"], 10, 64)
+						ipv4Address = attrs["ipv4_address"]
+						return err
+					},
+				),
+			},
+			// ImportState testing
+			{
+				ResourceName:      "binarylane_server_reverse_name.test",
+				ImportState:       true,
+				ImportStateVerify: true,
+				ImportStateIdFunc: func(s *terraform.State) (string, error) {
+					resourceState := s.RootModule().Resources["binarylane_server_reverse_name.test"]
+					return resourceState.Primary.Attributes["id"], nil
+				},
+			},
+			// Update and Read testing
+			{
+				Config: providerConfig + serverConfig + `
+resource "binarylane_server_reverse_name" "test" {
+  server_id    = binarylane_server.test.id
+  ipv4_address = binarylane_server.test.public_ipv4_addresses.0
+  reverse_name = "tf-test-ptr-updated.example.com" # Updated reverse name
+}
+`,
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttr("binarylane_server_reverse_name.test", "reverse_name", "tf-test-ptr-updated.example.com"),
+				),
+			},
+			// Removing the resource clears the reverse name while the server still exists
+			{
+				Config: providerConfig + serverConfig,
+				Check: func(_ *terraform.State) error {
+					return testAccCheckServerReverseNameCleared(serverId, ipv4Address)
+				},
+			},
+			// Delete testing automatically occurs in TestCase
+		},
+	})
+}
+
+func testAccCheckServerReverseNameCleared(serverId int64, ipv4Address string) error {
+	client, err := binarylane.NewClientWithConfig("", "")
+	if err != nil {
+		return err
+	}
+	resp, err := client.GetServersServerIdWithResponse(context.Background(), serverId)
+	if err != nil {
+		return err
+	}
+	if resp.StatusCode() == http.StatusNotFound {
+		return nil
+	}
+	if resp.StatusCode() != http.StatusOK {
+		return fmt.Errorf("unexpected status %s reading server %d: %s", resp.Status(), serverId, resp.Body)
+	}
+	for _, n := range resp.JSON200.Server.Networks.V4 {
+		if n.IpAddress != ipv4Address || n.ReverseName == nil {
+			continue
+		}
+		switch *n.ReverseName {
+		case "tf-test-ptr.example.com", "tf-test-ptr-updated.example.com":
+			return fmt.Errorf("reverse name for %s on server %d not cleared: %s", ipv4Address, serverId, *n.ReverseName)
+		}
+	}
+	return nil
+}

internal/provider/server_reverse_name_resource_unit_test.go

@@ -0,0 +1,141 @@
+package provider
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"terraform-provider-binarylane/internal/binarylane"
+
+	"github.com/hashicorp/terraform-plugin-framework/resource"
+	"github.com/hashicorp/terraform-plugin-framework/tfsdk"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-go/tftypes"
+)
+
+func TestServerReverseNameResourceUnit(t *testing.T) {
+	ctx := context.Background()
+
+	var (
+		postStatus  = http.StatusOK
+		serverFound = true
+		serverIp    = "203.0.113.7"
+		serverName  = "ptr.example.com"
+		lastBody    map[string]any
+	)
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch {
+		case r.Method == http.MethodPost && r.URL.Path == "/servers/1/actions":
+			b, _ := io.ReadAll(r.Body)
+			lastBody = nil
+			if err := json.Unmarshal(b, &lastBody); err != nil {
+				t.Errorf("decode POST body: %v", err)
+			}
+			w.WriteHeader(postStatus)
+			if postStatus == http.StatusOK {
+				_, _ = w.Write([]byte(`{"action":{"id":9,"status":"in-progress"}}`))
+			}
+		case r.Method == http.MethodGet && r.URL.Path == "/servers/1/actions/9":
+			_, _ = w.Write([]byte(`{"action":{"id":9,"status":"completed","completed_at":"2026-01-01T00:00:00Z"}}`))
+		case r.Method == http.MethodGet && r.URL.Path == "/servers/1":
+			if !serverFound {
+				w.WriteHeader(http.StatusNotFound)
+				return
+			}
+			_, _ = fmt.Fprintf(w, `{"server":{"id":1,"networks":{"v4":[{"ip_address":%q,"type":"public","reverse_name":%q}]}}}`, serverIp, serverName)
+		default:
+			t.Errorf("unexpected request %s %s", r.Method, r.URL.Path)
+			w.WriteHeader(http.StatusTeapot)
+		}
+	}))
+	defer srv.Close()
+
+	client, err := binarylane.NewClientWithConfig(srv.URL, "test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	r := &serverReverseNameResource{bc: &BinarylaneClient{client: client}}
+
+	schemaResp := resource.SchemaResponse{}
+	r.Schema(ctx, resource.SchemaRequest{}, &schemaResp)
+	s := schemaResp.Schema
+	emptyState := func() tfsdk.State {
+		return tfsdk.State{Schema: s, Raw: tftypes.NewValue(s.Type().TerraformType(ctx), nil)}
+	}
+	model := serverReverseNameResourceModel{
+		Id:          types.StringUnknown(),
+		ServerId:    types.Int64Value(1),
+		Ipv4Address: types.StringValue("203.0.113.7"),
+		ReverseName: types.StringValue("ptr.example.com"),
+	}
+	plan := tfsdk.Plan{Schema: s, Raw: tftypes.NewValue(s.Type().TerraformType(ctx), nil)}
+	if diags := plan.Set(ctx, &model); diags.HasError() {
+		t.Fatal(diags)
+	}
+
+	createResp := resource.CreateResponse{State: emptyState()}
+	r.Create(ctx, resource.CreateRequest{Plan: plan}, &createResp)
+	if createResp.Diagnostics.HasError() {
+		t.Fatal(createResp.Diagnostics)
+	}
+	if lastBody["reverse_name"] != "ptr.example.com" || lastBody["ipv4_address"] != "203.0.113.7" {
+		t.Fatalf("create: unexpected request body %v", lastBody)
+	}
+	state := createResp.State
+
+	read := func() (serverReverseNameResourceModel, bool) {
+		t.Helper()
+		readResp := resource.ReadResponse{State: state}
+		r.Read(ctx, resource.ReadRequest{State: state}, &readResp)
+		if readResp.Diagnostics.HasError() {
+			t.Fatal(readResp.Diagnostics)
+		}
+		if readResp.State.Raw.IsNull() {
+			return serverReverseNameResourceModel{}, false
+		}
+		var got serverReverseNameResourceModel
+		if diags := readResp.State.Get(ctx, &got); diags.HasError() {
+			t.Fatal(diags)
+		}
+		return got, true
+	}
+
+	serverName = "drifted.example.com"
+	if got, ok := read(); !ok || got.ReverseName.ValueString() != "drifted.example.com" {
+		t.Fatalf("read: expected drift to drifted.example.com, got %v (present=%v)", got.ReverseName, ok)
+	}
+
+	serverIp = "198.51.100.1"
+	if _, ok := read(); ok {
+		t.Fatal("read: expected state removed when IP is not on the server")
+	}
+
+	serverFound = false
+	if _, ok := read(); ok {
+		t.Fatal("read: expected state removed when server is 404")
+	}
+
+	postStatus = http.StatusAccepted
+	updateResp := resource.UpdateResponse{State: emptyState()}
+	r.Update(ctx, resource.UpdateRequest{Plan: plan, State: state}, &updateResp)
+	if updateResp.Diagnostics.HasError() {
+		t.Fatalf("update: 202 without action should succeed: %v", updateResp.Diagnostics)
+	}
+
+	deleteResp := resource.DeleteResponse{State: state}
+	r.Delete(ctx, resource.DeleteRequest{State: state}, &deleteResp)
+	if deleteResp.Diagnostics.HasError() {
+		t.Fatalf("delete: 202 without action should succeed: %v", deleteResp.Diagnostics)
+	}
+	if _, ok := lastBody["reverse_name"]; ok {
+		t.Fatalf("delete: request body must not contain reverse_name, got %v", lastBody)
+	}
+	if lastBody["ipv4_address"] != "203.0.113.7" {
+		t.Fatalf("delete: unexpected request body %v", lastBody)
+	}
+}