Files
seaweedfs/weed/s3api/iceberg/commit_helpers.go
T
Nguyễn Lộc Phúc 195f8156de fix(iceberg): keep a losing table create from deleting the winner's metadata (#12474)
* iceberg: keep a losing table create from deleting the winner's metadata

* iceberg: keep a staged file whose published record was renamed away

A create answers a conflict when its record was already visible and
another request changed it before the create could back it out. The
cleanup then looked only at the original name, so a record renamed in
between read as absent and the file it still points at was deleted.

S3 Tables now reports that case with a conflict of its own, and both
create paths keep the staged file on it instead of probing the name.
A conflict over a still-hidden record, lost to another create, still
removes the file.

* iceberg: discard a losing create's metadata only while it is still its own

The cleanup deleted the staged file by name. The path can be reused
before it runs: the table is dropped and purged, and another create
stages the same v1.metadata.json and registers it, which the losing
request then deleted.

Staged files now carry a per-request token in an internal extended
attribute, and the cleanup deletes with that token as the filer's
ExpectedExtended precondition, checked under the path lock the delete
runs under. A file that took the path since is left in place.

* iceberg: classify a typed S3 Tables error by its code, not its message

isS3TablesAlreadyExists matched "already exists" in the message before
looking at the code, so an InternalError whose text mentioned an
existing entry read as the name being taken: CreateTable answered 409
instead of 500, and registrationRefused discarded a staged file the
catalog may still point at. A typed error now decides by its code; only
an untyped one is matched by message.

* iceberg: pin stage-create on in the stage-create conflict test

Stage-create is on by default, but a shell that sets
ICEBERG_ENABLE_STAGE_CREATE=false turned the expected 409 into a 501.
Setting it in the test keeps the result independent of the environment.

* iceberg: test two creates overlapping at the canonical metadata name

The concurrent-creators test only lines the creators up before they
start, so whether two of them ever collide at v1.metadata.json is up to
the scheduler. The new test fixes the order: the second create runs
while the first has staged v1.metadata.json and not yet registered it.
It checks that every staging attempt is exclusive, that the second falls
back to v1-<uuid>, that both files hold their own metadata while both
are staged, and that the loser removes only its own file.

* s3tables: a create whose unmark write never went out stayed hidden

confirmChild counted any failure to take a create's mark off as possibly
published, the lookup that precedes the write included. That lookup
failing leaves the mark on, so the record stayed hidden; if another
create then adopted it, the back-out reported a published record that
changed, and the Iceberg catalog kept a staged file no record names.

The mark-removal calls now go through a wrapper that notes whether an
UpdateEntry went out without the filer refusing it. Only then may the
record have been seen. A refused compare, a missing entry, or a failure
before any write leaves the create's record hidden.

* s3tables: pass mayBeVisible into backOutChild

Fixes the build after rebasing onto the backOutChild split.
2026-11-07 10:54:04 -08:00

394 lines
16 KiB
Go

package iceberg
import (
"context"
"encoding/json"
"errors"
"fmt"
"math/rand/v2"
"net/http"
"strings"
"time"
"github.com/apache/iceberg-go/table"
"github.com/google/uuid"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
"github.com/seaweedfs/seaweedfs/weed/s3api/s3tables"
)
const requirementAssertCreate = "assert-create"
// sleepBeforeCommitRetry backs off between commit attempts, jittered so that
// writers that collided do not line up again on the next try.
func sleepBeforeCommitRetry(attempt int) {
jitter := time.Duration(rand.Int64N(int64(25 * time.Millisecond)))
time.Sleep(time.Duration(50*attempt)*time.Millisecond + jitter)
}
// stageCommitMetadata writes the metadata file a commit will point the catalog
// at, returning the name and location it landed on. The exclusive create keeps
// one writer from overwriting another's file; when the name is already taken
// the metadata goes to a unique one instead of failing, because the file there
// may be an orphan left by an interrupted commit, and refusing would wedge the
// table until an orphan sweep ran. The catalog pointer, not the file name,
// decides which commit won. This mirrors how the maintenance worker stages its
// own metadata.
func (s *Server) stageCommitMetadata(ctx context.Context, metadataBucket, metadataPath, location, metadataFileName string, metadataBytes []byte) (string, string, error) {
name, metadataLocation, _, err := s.stageOwnedMetadata(ctx, metadataBucket, metadataPath, location, metadataFileName, metadataBytes)
return name, metadataLocation, err
}
// stageOwnedMetadata is stageCommitMetadata that also returns the token the
// file was tagged with, which discardStagedMetadata needs to remove it.
func (s *Server) stageOwnedMetadata(ctx context.Context, metadataBucket, metadataPath, location, metadataFileName string, metadataBytes []byte) (string, string, string, error) {
token := uuid.NewString()
extended := map[string][]byte{stageTokenKey: []byte(token)}
err := s.saveMetadataBlob(ctx, metadataBucket, metadataPath, metadataFileName, metadataBytes, "application/json", true, extended)
if errors.Is(err, filer_pb.ErrEntryAlreadyExists) {
// v{N}-{uuid}, a form both the catalog and the maintenance worker
// still read the version from.
metadataFileName = fmt.Sprintf("%s-%s.metadata.json", strings.TrimSuffix(metadataFileName, ".metadata.json"), uuid.NewString())
glog.V(1).Infof("Iceberg: metadata file already staged for %s, using %s", location, metadataFileName)
err = s.saveMetadataBlob(ctx, metadataBucket, metadataPath, metadataFileName, metadataBytes, "application/json", true, extended)
}
if err != nil {
return "", "", "", err
}
return metadataFileName, fmt.Sprintf("%s/metadata/%s", strings.TrimSuffix(location, "/"), metadataFileName), token, nil
}
// discardStagedMetadata removes a metadata file this request staged and the
// catalog will never point at. metadataFileName and token must be what
// stageOwnedMetadata returned. The name alone does not identify the file: the
// path can be reused once this request's file is gone — the table dropped and
// its directory purged, then a new create staging the same v1.metadata.json —
// so the delete goes through only while the entry still carries this
// request's token, and a replacement is left alone.
func (s *Server) discardStagedMetadata(ctx context.Context, metadataBucket, metadataPath, metadataFileName, metadataLocation, token string) {
err := s.deleteStagedMetadataFile(ctx, metadataBucket, metadataPath, metadataFileName, token)
if errors.Is(err, errStagedFileReplaced) {
glog.V(1).Infof("Iceberg: keeping metadata file %s, it is no longer the one this request staged: %v", metadataLocation, err)
return
}
if err != nil {
glog.V(1).Infof("Iceberg: failed to cleanup metadata file %s after the catalog refused it: %v", metadataLocation, err)
}
}
// registrationRefused reports whether a failed registration was refused
// before any record pointing at the staged file became visible, so the file can
// go. A name already taken, a conflict, and any other 4xx are refused that way:
// the create wrote nothing, or backed out what it wrote, or lost its
// still-hidden record to another create. One conflict is not: a create whose
// record was already visible, and was updated or renamed away before the
// create could back it out, leaves that record in place — under the original
// name or another — still pointing at the file. A transport failure or 5xx is
// not a refusal either: the record may have been written before the error
// surfaced.
func registrationRefused(err error) bool {
if s3tables.IsPublishedTableChanged(err) {
return false
}
if isS3TablesConflict(err) || isS3TablesAlreadyExists(err) {
return true
}
status, _, _ := classifyManagerError(err)
return status >= 400 && status < 500
}
type icebergRequestError struct {
status int
errType string
message string
}
type createOnCommitInput struct {
bucketARN string
markerBucket string
namespace []string
tableName string
identityName string
location string
tableUUID uuid.UUID
baseMetadata table.Metadata
baseMetadataLoc string
baseMetadataVer int
updates table.Updates
statisticsUpdates []statisticsUpdate
}
func isS3TablesConflict(err error) bool {
if err == nil {
return false
}
if errors.Is(err, s3tables.ErrVersionTokenMismatch) {
return true
}
var tableErr *s3tables.S3TablesError
return errors.As(err, &tableErr) && tableErr.Type == s3tables.ErrCodeConflict
}
func isS3TablesNotFound(err error) bool {
if err == nil {
return false
}
if strings.Contains(strings.ToLower(err.Error()), "not found") {
return true
}
var tableErr *s3tables.S3TablesError
return errors.As(err, &tableErr) &&
(tableErr.Type == s3tables.ErrCodeNoSuchTable || tableErr.Type == s3tables.ErrCodeNoSuchNamespace || strings.Contains(strings.ToLower(tableErr.Message), "not found"))
}
func hasAssertCreateRequirement(requirements table.Requirements) bool {
for _, requirement := range requirements {
if requirement.GetType() == requirementAssertCreate {
return true
}
}
return false
}
// isS3TablesAlreadyExists reports whether err says the name is already taken.
// A typed error says so through its code alone: a server fault whose message
// happens to mention an existing entry is still a server fault, and taking it
// for a refusal would answer 409 and discard a file the catalog may point at.
// Only an untyped error is read by its message.
func isS3TablesAlreadyExists(err error) bool {
if err == nil {
return false
}
var tableErr *s3tables.S3TablesError
if errors.As(err, &tableErr) {
return tableErr.Type == s3tables.ErrCodeTableAlreadyExists || tableErr.Type == s3tables.ErrCodeNamespaceAlreadyExists
}
return strings.Contains(strings.ToLower(err.Error()), "already exists")
}
func (s *Server) finalizeCreateOnCommit(ctx context.Context, input createOnCommitInput) (*CommitTableResponse, *icebergRequestError) {
builder, err := table.MetadataBuilderFromBase(input.baseMetadata, input.baseMetadataLoc)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Failed to create metadata builder: " + err.Error(),
}
}
for _, update := range input.updates {
if err := update.Apply(builder); err != nil {
return nil, &icebergRequestError{
status: http.StatusBadRequest,
errType: "BadRequestException",
message: "Failed to apply update: " + err.Error(),
}
}
}
newMetadata, err := builder.Build()
if err != nil {
return nil, &icebergRequestError{
status: http.StatusBadRequest,
errType: "BadRequestException",
message: "Failed to build new metadata: " + err.Error(),
}
}
metadataVersion := input.baseMetadataVer + 1
if metadataVersion <= 0 {
metadataVersion = 1
}
metadataFileName := fmt.Sprintf("v%d.metadata.json", metadataVersion)
metadataBytes, err := json.Marshal(newMetadata)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Failed to serialize metadata: " + err.Error(),
}
}
metadataBytes, err = applyStatisticsUpdates(metadataBytes, input.statisticsUpdates)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusBadRequest,
errType: "BadRequestException",
message: "Failed to apply statistics updates: " + err.Error(),
}
}
metadataBytes = refreshDefaultNameMapping(metadataBytes, newMetadata)
// Same spec-compliance fixup we apply on create-table; ensures
// v{N}.metadata.json files written through this create-on-commit path are
// also readable by strict Iceberg clients reading directly from S3.
metadataBytes = ensureMetadataSpecCompliance(metadataBytes)
newMetadata, err = table.ParseMetadataBytes(metadataBytes)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Failed to parse committed metadata: " + err.Error(),
}
}
metadataBucket, metadataPath, err := parseS3Location(input.location)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Invalid table location: " + err.Error(),
}
}
if err := confineMetadataLocation(metadataBucket, metadataPath, input.markerBucket); err != nil {
return nil, &icebergRequestError{
status: http.StatusBadRequest,
errType: "BadRequestException",
message: err.Error(),
}
}
// Two creators racing for the same table both pick this name. Staging it
// exclusively gives each its own file, so the loser can discard its file
// below without deleting the one the winner's record points at.
metadataFileName, newMetadataLocation, stageToken, err := s.stageOwnedMetadata(ctx, metadataBucket, metadataPath, input.location, metadataFileName, metadataBytes)
if err != nil {
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Failed to save metadata file: " + err.Error(),
}
}
createReq := &s3tables.CreateTableRequest{
TableBucketARN: input.bucketARN,
Namespace: input.namespace,
Name: input.tableName,
Format: "ICEBERG",
Metadata: &s3tables.TableMetadata{
Iceberg: &s3tables.IcebergMetadata{
TableUUID: input.tableUUID.String(),
},
FullMetadata: metadataBytes,
},
MetadataVersion: metadataVersion,
MetadataLocation: newMetadataLocation,
}
var createResp s3tables.CreateTableResponse
createErr := s.filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
mgrClient := s3tables.NewManagerClient(client)
return s.tablesManager.Execute(ctx, mgrClient, "CreateTable", createReq, &createResp, input.identityName)
})
tableCreatedConcurrently := &icebergRequestError{
status: http.StatusConflict,
errType: "CommitFailedException",
message: "Table was created concurrently",
}
if createErr != nil {
if registrationRefused(createErr) {
s.discardStagedMetadata(ctx, metadataBucket, metadataPath, metadataFileName, newMetadataLocation, stageToken)
}
if isS3TablesConflict(createErr) || isS3TablesAlreadyExists(createErr) {
return nil, tableCreatedConcurrently
}
glog.Errorf("Iceberg: CommitTable CreateTable error: %v", createErr)
return nil, &icebergRequestError{
status: http.StatusInternalServerError,
errType: "InternalServerError",
message: "Failed to commit table creation: " + createErr.Error(),
}
}
// A name that already holds a table is answered with that table's own
// location rather than an error: another creator won the race. That
// location is empty for a table registered without one.
if createResp.MetadataLocation != newMetadataLocation {
s.discardStagedMetadata(ctx, metadataBucket, metadataPath, metadataFileName, newMetadataLocation, stageToken)
return nil, tableCreatedConcurrently
}
markerBucket := input.markerBucket
if markerBucket == "" {
markerBucket = metadataBucket
}
if markerErr := s.deleteStageCreateMarkers(ctx, markerBucket, input.namespace, input.tableName); markerErr != nil {
glog.V(1).Infof("Iceberg: failed to cleanup stage-create markers for %s.%s after finalize: %v", flattenNamespacePath(input.namespace), input.tableName, markerErr)
}
return &CommitTableResponse{
MetadataLocation: newMetadataLocation,
Metadata: newMetadata,
}, nil
}
// Manager requests are size-capped like registrations, so a commit whose new
// metadata is too large to ride along flips the pointer by location alone —
// the staged file already holds it. The record's stored copy must be cleared
// with it, or loads would keep serving the pre-commit bytes.
func fitUpdateTableRequest(req *s3tables.UpdateTableRequest) {
if req.Metadata == nil || len(req.Metadata.FullMetadata) == 0 {
return
}
if body, err := json.Marshal(req); err == nil && len(body) <= s3tables.MaxRequestBodySize {
return
}
req.Metadata = &s3tables.TableMetadata{Iceberg: req.Metadata.Iceberg}
req.ClearFullMetadata = true
}
// authorizeCommit asks the S3 Tables layer, before anything is written, whether
// the caller may update the table. Both commit paths stage the new metadata
// file in the table's directory before UpdateTable authorizes the pointer
// flip, so without this gate a caller who may only read the table could still
// make the server write and delete files under it. UpdateTable decides again
// when the pointer flips.
func (s *Server) authorizeCommit(ctx context.Context, bucketARN string, namespace []string, tableName, identityName string) *icebergRequestError {
err := s.filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
return s.tablesManager.AuthorizeUpdateTable(ctx, s3tables.NewManagerClient(client), &s3tables.UpdateTableRequest{
TableBucketARN: bucketARN,
Namespace: namespace,
Name: tableName,
}, identityName)
})
if err == nil {
bucketName, _ := s3tables.ParseBucketNameFromARN(bucketARN)
err = s.tablesManager.CheckVectorNamespaceWrite(ctx, s.filerClient, bucketName, namespace)
}
if err == nil {
return nil
}
var tableErr *s3tables.S3TablesError
if errors.As(err, &tableErr) {
switch tableErr.Type {
case s3tables.ErrCodeAccessDenied:
return &icebergRequestError{http.StatusForbidden, "ForbiddenException", fmt.Sprintf("Not authorized to commit to table %s", tableName)}
case s3tables.ErrCodeNoSuchTable, s3tables.ErrCodeNoSuchNamespace:
return &icebergRequestError{http.StatusNotFound, "NoSuchTableException", fmt.Sprintf("Table does not exist: %s", tableName)}
}
}
glog.V(1).Infof("Iceberg: commit authorization for %s failed: %v", tableName, err)
return &icebergRequestError{http.StatusInternalServerError, "InternalServerError", "Failed to authorize commit: " + err.Error()}
}
// authorizeViewCommit is authorizeCommit for a view, whose update path stages
// its metadata file before UpdateView authorizes the pointer flip.
func (s *Server) authorizeViewCommit(ctx context.Context, bucketARN string, namespace []string, viewName, identityName string) *icebergRequestError {
err := s.filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
return s.tablesManager.AuthorizeUpdateView(ctx, s3tables.NewManagerClient(client), &s3tables.UpdateViewRequest{
TableBucketARN: bucketARN,
Namespace: namespace,
Name: viewName,
}, identityName)
})
if err == nil {
return nil
}
var tableErr *s3tables.S3TablesError
if errors.As(err, &tableErr) {
switch tableErr.Type {
case s3tables.ErrCodeAccessDenied:
return &icebergRequestError{http.StatusForbidden, "ForbiddenException", fmt.Sprintf("Not authorized to commit to view %s", viewName)}
case s3tables.ErrCodeNoSuchView, s3tables.ErrCodeNoSuchNamespace:
return &icebergRequestError{http.StatusNotFound, "NoSuchViewException", fmt.Sprintf("View does not exist: %s", viewName)}
}
}
glog.V(1).Infof("Iceberg: view commit authorization for %s failed: %v", viewName, err)
return &icebergRequestError{http.StatusInternalServerError, "InternalServerError", "Failed to authorize commit: " + err.Error()}
}