r/aws_iam_user_policies_exclusive: new resource

This resource will enable exclusive management of IAM user policy
attachments via Terraform.

```console
% make testacc PKG=iam TESTS=TestAccIAMUserPoliciesExclusive_
make: Verifying source code with gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go1.23.1 test ./internal/service/iam/... -v -count 1 -parallel 20 -run='TestAccIAMUserPoliciesExclusive_'  -timeout 360m

--- PASS: TestAccIAMUserPoliciesExclusive_empty (14.20s)
--- PASS: TestAccIAMUserPoliciesExclusive_disappears_User (14.87s)
--- PASS: TestAccIAMUserPoliciesExclusive_basic (16.78s)
--- PASS: TestAccIAMUserPoliciesExclusive_outOfBandRemoval (23.39s)
--- PASS: TestAccIAMUserPoliciesExclusive_outOfBandAddition (23.42s)
--- PASS: TestAccIAMUserPoliciesExclusive_multiple (25.27s)
PASS
ok      github.com/hashicorp/terraform-provider-aws/internal/service/iam        32.023s
```

.changelog/39544.txt

@@ -0,0 +1,3 @@
+```release-note:new-resource
+aws_iam_user_policies_exclusive
+```

internal/service/iam/exports_test.go

@@ -49,6 +49,7 @@ var (
 	FindServerCertificateByName         = findServerCertificateByName
 	FindSSHPublicKeyByThreePartKey      = findSSHPublicKeyByThreePartKey
 	FindUserByName                      = findUserByName
+	FindUserPoliciesByName              = findUserPoliciesByName
 	FindVirtualMFADeviceBySerialNumber  = findVirtualMFADeviceBySerialNumber
 	SESSMTPPasswordFromSecretKeySigV4   = sesSMTPPasswordFromSecretKeySigV4
 )

internal/service/iam/user_policies_exclusive.go

@@ -0,0 +1,217 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package iam
+
+import (
+	"context"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/service/iam"
+	awstypes "github.com/aws/aws-sdk-go-v2/service/iam/types"
+	"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/planmodifier"
+	"github.com/hashicorp/terraform-plugin-framework/resource/schema/stringplanmodifier"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/retry"
+	"github.com/hashicorp/terraform-provider-aws/internal/create"
+	"github.com/hashicorp/terraform-provider-aws/internal/errs"
+	intflex "github.com/hashicorp/terraform-provider-aws/internal/flex"
+	"github.com/hashicorp/terraform-provider-aws/internal/framework"
+	"github.com/hashicorp/terraform-provider-aws/internal/framework/flex"
+	"github.com/hashicorp/terraform-provider-aws/internal/tfresource"
+	"github.com/hashicorp/terraform-provider-aws/names"
+)
+
+// @FrameworkResource("aws_iam_user_policies_exclusive", name="User Policies Exclusive")
+func newResourceUserPoliciesExclusive(_ context.Context) (resource.ResourceWithConfigure, error) {
+	return &resourceUserPoliciesExclusive{}, nil
+}
+
+const (
+	ResNameUserPoliciesExclusive = "User Policies Exclusive"
+)
+
+type resourceUserPoliciesExclusive struct {
+	framework.ResourceWithConfigure
+	framework.WithNoOpDelete
+}
+
+func (r *resourceUserPoliciesExclusive) Metadata(_ context.Context, req resource.MetadataRequest, resp *resource.MetadataResponse) {
+	resp.TypeName = "aws_iam_user_policies_exclusive"
+}
+
+func (r *resourceUserPoliciesExclusive) Schema(ctx context.Context, req resource.SchemaRequest, resp *resource.SchemaResponse) {
+	resp.Schema = schema.Schema{
+		Attributes: map[string]schema.Attribute{
+			names.AttrUserName: schema.StringAttribute{
+				Required: true,
+				PlanModifiers: []planmodifier.String{
+					stringplanmodifier.RequiresReplace(),
+				},
+			},
+			"policy_names": schema.SetAttribute{
+				ElementType: types.StringType,
+				Required:    true,
+			},
+		},
+	}
+}
+
+func (r *resourceUserPoliciesExclusive) Create(ctx context.Context, req resource.CreateRequest, resp *resource.CreateResponse) {
+	var plan resourceUserPoliciesExclusiveData
+	resp.Diagnostics.Append(req.Plan.Get(ctx, &plan)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	var policyNames []string
+	resp.Diagnostics.Append(plan.PolicyNames.ElementsAs(ctx, &policyNames, false)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	err := r.syncAttachments(ctx, plan.UserName.ValueString(), policyNames)
+	if err != nil {
+		resp.Diagnostics.AddError(
+			create.ProblemStandardMessage(names.IAM, create.ErrActionCreating, ResNameUserPoliciesExclusive, plan.UserName.String(), err),
+			err.Error(),
+		)
+		return
+	}
+
+	resp.Diagnostics.Append(resp.State.Set(ctx, plan)...)
+}
+
+func (r *resourceUserPoliciesExclusive) Read(ctx context.Context, req resource.ReadRequest, resp *resource.ReadResponse) {
+	conn := r.Meta().IAMClient(ctx)
+
+	var state resourceUserPoliciesExclusiveData
+	resp.Diagnostics.Append(req.State.Get(ctx, &state)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	out, err := findUserPoliciesByName(ctx, conn, state.UserName.ValueString())
+	if tfresource.NotFound(err) {
+		resp.State.RemoveResource(ctx)
+		return
+	}
+	if err != nil {
+		resp.Diagnostics.AddError(
+			create.ProblemStandardMessage(names.IAM, create.ErrActionReading, ResNameUserPoliciesExclusive, state.UserName.String(), err),
+			err.Error(),
+		)
+		return
+	}
+
+	state.PolicyNames = flex.FlattenFrameworkStringValueSetLegacy(ctx, out)
+	resp.Diagnostics.Append(resp.State.Set(ctx, &state)...)
+}
+
+func (r *resourceUserPoliciesExclusive) Update(ctx context.Context, req resource.UpdateRequest, resp *resource.UpdateResponse) {
+	var plan, state resourceUserPoliciesExclusiveData
+	resp.Diagnostics.Append(req.Plan.Get(ctx, &plan)...)
+	resp.Diagnostics.Append(req.State.Get(ctx, &state)...)
+	if resp.Diagnostics.HasError() {
+		return
+	}
+
+	if !plan.PolicyNames.Equal(state.PolicyNames) {
+		var policyNames []string
+		resp.Diagnostics.Append(plan.PolicyNames.ElementsAs(ctx, &policyNames, false)...)
+		if resp.Diagnostics.HasError() {
+			return
+		}
+
+		err := r.syncAttachments(ctx, plan.UserName.ValueString(), policyNames)
+		if err != nil {
+			resp.Diagnostics.AddError(
+				create.ProblemStandardMessage(names.IAM, create.ErrActionUpdating, ResNameUserPoliciesExclusive, plan.UserName.String(), err),
+				err.Error(),
+			)
+			return
+		}
+	}
+
+	resp.Diagnostics.Append(resp.State.Set(ctx, &plan)...)
+}
+
+// syncAttachments handles keeping the configured inline policy attachments
+// in sync with the remote resource.
+//
+// Inline policies defined on this resource but not attached to the user will
+// be added. Policies attached to the user but not configured on this resource
+// will be removed.
+func (r *resourceUserPoliciesExclusive) syncAttachments(ctx context.Context, userName string, want []string) error {
+	conn := r.Meta().IAMClient(ctx)
+
+	have, err := findUserPoliciesByName(ctx, conn, userName)
+	if err != nil {
+		return err
+	}
+
+	create, remove, _ := intflex.DiffSlices(have, want, func(s1, s2 string) bool { return s1 == s2 })
+
+	for _, name := range create {
+		in := &iam.PutUserPolicyInput{
+			UserName:   aws.String(userName),
+			PolicyName: aws.String(name),
+		}
+
+		_, err := conn.PutUserPolicy(ctx, in)
+		if err != nil {
+			return err
+		}
+	}
+
+	for _, name := range remove {
+		in := &iam.DeleteUserPolicyInput{
+			UserName:   aws.String(userName),
+			PolicyName: aws.String(name),
+		}
+
+		_, err := conn.DeleteUserPolicy(ctx, in)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (r *resourceUserPoliciesExclusive) ImportState(ctx context.Context, req resource.ImportStateRequest, resp *resource.ImportStateResponse) {
+	resource.ImportStatePassthroughID(ctx, path.Root(names.AttrUserName), req, resp)
+}
+
+func findUserPoliciesByName(ctx context.Context, conn *iam.Client, userName string) ([]string, error) {
+	in := &iam.ListUserPoliciesInput{
+		UserName: aws.String(userName),
+	}
+
+	var policyNames []string
+	paginator := iam.NewListUserPoliciesPaginator(conn, in)
+	for paginator.HasMorePages() {
+		page, err := paginator.NextPage(ctx)
+		if err != nil {
+			if errs.IsA[*awstypes.NoSuchEntityException](err) {
+				return nil, &retry.NotFoundError{
+					LastError:   err,
+					LastRequest: in,
+				}
+			}
+			return policyNames, err
+		}
+
+		policyNames = append(policyNames, page.PolicyNames...)
+	}
+
+	return policyNames, nil
+}
+
+type resourceUserPoliciesExclusiveData struct {
+	UserName    types.String `tfsdk:"user_name"`
+	PolicyNames types.Set    `tfsdk:"policy_names"`
+}