fix: return InvalidArgument for an empty website configuration

* fix: return InvalidArgument for an empty website configuration

`PutBucketWebsite` parsed an empty `<WebsiteConfiguration/>` into a zero-value config, and `WebsiteConfiguration.Validate` reported the nil `IndexDocument` as `MalformedXML`. S3 reports the missing index document as an `InvalidArgument` request error naming the argument instead:

    InvalidArgument: A value for IndexDocument Suffix must be provided if RedirectAllRequestsTo is empty

That branch now returns the error with `ArgumentName=IndexDocument` and `ArgumentValue=null`, matching the response in the report. Genuinely malformed XML, and a `RedirectAllRequestsTo` that conflicts with the other fields, still return `MalformedXML`.

Fixes #2260

* test: cover an empty website configuration in the PutBucketWebsite integration suite

Add a `PutBucketWebsite_empty_configuration` case that sends the empty `<WebsiteConfiguration/>` payload from the report and asserts the `InvalidArgument` response, including `ArgumentName=IndexDocument` and `ArgumentValue=null`.

The SDK collapses the error into a generic API error that drops the argument fields, so the request is signed by hand and the raw response checked with `checkHTTPResponseApiErr`, the same helper the other argument-field assertions use. The case fails against the previous behaviour with `expected error code to be InvalidArgument, instead got MalformedXML`.

---------

Co-authored-by: Tung Lam <lamphamabtung96@gmail.com>

s3api/controllers/bucket-put_test.go

@@ -1334,3 +1334,111 @@ func TestS3ApiController_PutBucketAcl(t *testing.T) {
 		})
 	}
 }
+
+func TestS3ApiController_PutBucketWebsite(t *testing.T) {
+	validBody, err := xml.Marshal(s3response.WebsiteConfiguration{
+		IndexDocument: &s3response.IndexDocument{Suffix: "index.html"},
+	})
+	assert.NoError(t, err)
+
+	// The payload from https://github.com/versity/versitygw/issues/2260
+	emptyBody := []byte(`<?xml version="1.0" encoding="UTF-8"?>
+<WebsiteConfiguration xmlns="https://s3.amazonaws.com/doc/2006-03-01/"></WebsiteConfiguration>`)
+
+	tests := []struct {
+		name   string
+		input  testInput
+		output testOutput
+	}{
+		{
+			name: "verify access fails",
+			input: testInput{
+				locals: accessDeniedLocals,
+			},
+			output: testOutput{
+				response: &Response{
+					MetaOpts: &MetaOptions{
+						BucketOwner: "root",
+					},
+				},
+				err: s3err.GetAPIError(s3err.ErrAccessDenied),
+			},
+		},
+		{
+			name: "empty website configuration",
+			input: testInput{
+				locals: defaultLocals,
+				body:   emptyBody,
+			},
+			output: testOutput{
+				response: &Response{
+					MetaOpts: &MetaOptions{BucketOwner: "root"},
+				},
+				err: s3err.GetInvalidArgumentErr(s3err.InvalidArgMissingIndexDocumentSuffix, "null"),
+			},
+		},
+		{
+			name: "malformed xml",
+			input: testInput{
+				locals: defaultLocals,
+				body:   []byte("<WebsiteConfiguration><IndexDocument>"),
+			},
+			output: testOutput{
+				response: &Response{
+					MetaOpts: &MetaOptions{BucketOwner: "root"},
+				},
+				err: s3err.GetAPIError(s3err.ErrMalformedXML),
+			},
+		},
+		{
+			name: "backend error",
+			input: testInput{
+				locals: defaultLocals,
+				beErr:  s3err.GetAPIError(s3err.ErrNoSuchBucket),
+				body:   validBody,
+			},
+			output: testOutput{
+				response: &Response{
+					MetaOpts: &MetaOptions{BucketOwner: "root"},
+				},
+				err: s3err.GetAPIError(s3err.ErrNoSuchBucket),
+			},
+		},
+		{
+			name: "success",
+			input: testInput{
+				locals: defaultLocals,
+				body:   validBody,
+			},
+			output: testOutput{
+				response: &Response{
+					MetaOpts: &MetaOptions{
+						BucketOwner: "root",
+					},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			be := &BackendMock{
+				PutBucketWebsiteFunc: func(contextMoqParam context.Context, bucket string, website []byte) error {
+					return tt.input.beErr
+				},
+				GetBucketPolicyFunc: func(contextMoqParam context.Context, bucket string) ([]byte, error) {
+					return nil, s3err.GetAPIError(s3err.ErrAccessDenied)
+				},
+			}
+
+			ctrl := S3ApiController{
+				be: be,
+			}
+
+			testController(t, ctrl.PutBucketWebsite, tt.output.response, tt.output.err, ctxInputs{
+				locals: tt.input.locals,
+				body:   tt.input.body,
+			})
+		})
+	}
+}

s3err/invalid-argument.go

@@ -60,6 +60,7 @@ const (
 	InvalidArgOnlyAws4HmacSha256
 	InvalidArgDateHeader
 	InvalidArgIndexDocumentSuffix
+	InvalidArgMissingIndexDocumentSuffix
 	InvalidArgErrorDocumentKey
 )
 
@@ -208,6 +209,10 @@ var invalidArgErrResponses = map[InvalidArgErrorCode]InvalidArgumentError{
 		Description:  "The IndexDocument Suffix is not well formed",
 		ArgumentName: "IndexDocument",
 	},
+	InvalidArgMissingIndexDocumentSuffix: {
+		Description:  "A value for IndexDocument Suffix must be provided if RedirectAllRequestsTo is empty",
+		ArgumentName: "IndexDocument",
+	},
 	InvalidArgErrorDocumentKey: {
 		Description:  "The ErrorDocument Key is not well formed",
 		ArgumentName: "ErrorDocument",

s3response/website.go

@@ -91,7 +91,8 @@ func (c *WebsiteConfiguration) Validate() error {
 
 	if c.IndexDocument == nil {
 		debuglogger.Logf("website index document is missing")
-		return s3err.GetAPIError(s3err.ErrMalformedXML)
+		// S3 reports the absent suffix value as the literal "null".
+		return s3err.GetInvalidArgumentErr(s3err.InvalidArgMissingIndexDocumentSuffix, "null")
 	}
 	if c.IndexDocument.Suffix == "" {
 		debuglogger.Logf("website index suffix is empty")

s3response/website_test.go

@@ -70,7 +70,7 @@ func TestWebsiteConfiguration_Validate(t *testing.T) {
 			name:    "missing index document",
 			config:  WebsiteConfiguration{},
 			wantErr: true,
-			errCode: "MalformedXML",
+			errCode: "InvalidArgument",
 		},
 		{
 			name: "empty index suffix",

tests/integration/PutBucketWebsite.go

@@ -17,7 +17,9 @@ package integration
 import (
 	"context"
 	"fmt"
+	"net/http"
 	"strings"
+	"time"
 
 	"github.com/aws/aws-sdk-go-v2/service/s3"
 	"github.com/aws/aws-sdk-go-v2/service/s3/types"
@@ -60,6 +62,34 @@ func PutBucketWebsite_empty_suffix(s *S3Conf) error {
 	})
 }
 
+func PutBucketWebsite_empty_configuration(s *S3Conf) error {
+	testName := "PutBucketWebsite_empty_configuration"
+	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {
+		// The payload from https://github.com/versity/versitygw/issues/2260
+		body := []byte(`<?xml version="1.0" encoding="UTF-8"?>
+<WebsiteConfiguration xmlns="https://s3.amazonaws.com/doc/2006-03-01/"></WebsiteConfiguration>`)
+
+		// The SDK collapses the error into a generic API error that drops the
+		// ArgumentName and ArgumentValue fields, so the request is signed by
+		// hand and the raw error body checked.
+		req, err := createSignedReq(http.MethodPut, s.endpoint,
+			fmt.Sprintf("%v?website=", bucket), s.awsID, s.awsSecret,
+			"s3", s.awsRegion, "", body, time.Now(),
+			map[string]string{"Content-Type": "application/xml"})
+		if err != nil {
+			return err
+		}
+
+		resp, err := s.httpClient.Do(req)
+		if err != nil {
+			return err
+		}
+
+		return checkHTTPResponseApiErr(resp,
+			s3err.GetInvalidArgumentErr(s3err.InvalidArgMissingIndexDocumentSuffix, "null"))
+	})
+}
+
 func PutBucketWebsite_suffix_with_slash(s *S3Conf) error {
 	testName := "PutBucketWebsite_suffix_with_slash"
 	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {

tests/integration/group-tests.go

@@ -687,6 +687,7 @@ func TestDeleteBucketCors(ts *TestState) {
 func TestPutBucketWebsite(ts *TestState) {
 	ts.Run(PutBucketWebsite_non_existing_bucket)
 	ts.Run(PutBucketWebsite_empty_suffix)
+	ts.Run(PutBucketWebsite_empty_configuration)
 	ts.Run(PutBucketWebsite_suffix_with_slash)
 	ts.Run(PutBucketWebsite_invalid_redirect_protocol)
 	ts.Run(PutBucketWebsite_redirectAll_index_error_routingRules)
@@ -3235,6 +3236,7 @@ func GetIntTests() IntTests {
 		"PutBucketCors_success":                                                            PutBucketCors_success,
 		"PutBucketWebsite_non_existing_bucket":                                             PutBucketWebsite_non_existing_bucket,
 		"PutBucketWebsite_empty_suffix":                                                    PutBucketWebsite_empty_suffix,
+		"PutBucketWebsite_empty_configuration":                                             PutBucketWebsite_empty_configuration,
 		"PutBucketWebsite_suffix_with_slash":                                               PutBucketWebsite_suffix_with_slash,
 		"PutBucketWebsite_invalid_redirect_protocol":                                       PutBucketWebsite_invalid_redirect_protocol,
 		"PutBucketWebsite_redirectAll_index_error_routingRules":                            PutBucketWebsite_redirectAll_index_error_routingRules,