Heal recursively all entries in config/ prefix (#6545)

This to ensure that we heal all entries in config/
prefix, we will have IAM and STS related files which
are being introduced in #6168 PR

This is a change to ensure that we heal all of them
properly, not just `config.json`

cmd/admin-heal-ops.go

@@ -20,7 +20,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"path"
 	"runtime"
 	"strings"
 	"sync"
@@ -386,7 +385,6 @@ func (h *healSequence) stop() {
 // sequence automatically resumes. The return value indicates if the
 // operation succeeded.
 func (h *healSequence) pushHealResultItem(r madmin.HealResultItem) error {
-
 	// start a timer to keep an upper time limit to find an empty
 	// slot to add the given heal result - if no slot is found it
 	// means that the server is holding the maximum amount of
@@ -543,24 +541,64 @@ func (h *healSequence) healConfig() error {
 		return errServerNotInitialized
 	}
 
-	configFile := path.Join(minioConfigPrefix, minioConfigFile)
-	configBackupFile := path.Join(minioConfigPrefix, minioConfigBackupFile)
-	for _, cfg := range []string{configFile, configBackupFile} {
-		res, err := objectAPI.HealObject(h.ctx, minioMetaBucket, cfg, h.settings.DryRun)
+	// NOTE: Healing on configs is run regardless
+	// of any bucket being selected, this is to ensure that
+	// configs are always uptodate and correct.
+	marker := ""
+	isTruncated := true
+	for isTruncated {
+		if globalHTTPServer != nil {
+			// Wait at max 1 minute for an inprogress request
+			// before proceeding to heal
+			waitCount := 60
+			// Any requests in progress, delay the heal.
+			for globalHTTPServer.GetRequestCount() > 0 && waitCount > 0 {
+				waitCount--
+				time.Sleep(1 * time.Second)
+			}
+		}
+
+		// Lists all objects under `config` prefix.
+		objectInfos, err := objectAPI.ListObjectsHeal(h.ctx, minioMetaBucket, minioConfigPrefix,
+			marker, "", 1000)
 		if err != nil {
-			return err
+			return errFnHealFromAPIErr(err)
+		}
+
+		for index := range objectInfos.Objects {
+			if h.isQuitting() {
+				return errHealStopSignalled
+			}
+			o := objectInfos.Objects[index]
+			res, herr := objectAPI.HealObject(h.ctx, o.Bucket, o.Name, h.settings.DryRun)
+			// Object might have been deleted, by the time heal
+			// was attempted we ignore this file an move on.
+			if isErrObjectNotFound(herr) {
+				continue
+			}
+			if herr != nil {
+				return herr
 			}
 			res.Type = madmin.HealItemBucketMetadata
 			if err = h.pushHealResultItem(res); err != nil {
 				return err
 			}
 		}
+
+		isTruncated = objectInfos.IsTruncated
+		marker = objectInfos.NextMarker
+	}
+
 	return nil
 }
 
 // healDiskFormat - heals format.json, return value indicates if a
 // failure error occurred.
 func (h *healSequence) healDiskFormat() error {
+	if h.isQuitting() {
+		return errHealStopSignalled
+	}
+
 	// Get current object layer instance.
 	objectAPI := newObjectLayerFn()
 	if objectAPI == nil {
@@ -586,6 +624,10 @@ func (h *healSequence) healDiskFormat() error {
 
 // healBuckets - check for all buckets heal or just particular bucket.
 func (h *healSequence) healBuckets() error {
+	if h.isQuitting() {
+		return errHealStopSignalled
+	}
+
 	// 1. If a bucket was specified, heal only the bucket.
 	if h.bucket != "" {
 		return h.healBucket(h.bucket)
@@ -613,10 +655,6 @@ func (h *healSequence) healBuckets() error {
 
 // healBucket - traverses and heals given bucket
 func (h *healSequence) healBucket(bucket string) error {
-	if h.isQuitting() {
-		return errHealStopSignalled
-	}
-
 	// Get current object layer instance.
 	objectAPI := newObjectLayerFn()
 	if objectAPI == nil {
@@ -641,8 +679,7 @@ func (h *healSequence) healBucket(bucket string) error {
 			// and if so heal it.
 			_, err = objectAPI.GetObjectInfo(h.ctx, bucket, h.objPrefix, ObjectOptions{})
 			if err == nil {
-				err = h.healObject(bucket, h.objPrefix)
-				if err != nil {
+				if err = h.healObject(bucket, h.objPrefix); err != nil {
 					return err
 				}
 			}
@@ -708,6 +745,9 @@ func (h *healSequence) healObject(bucket, object string) error {
 	}
 
 	hri, err := objectAPI.HealObject(h.ctx, bucket, object, h.settings.DryRun)
+	if isErrObjectNotFound(err) {
+		return nil
+	}
 	if err != nil {
 		hri.Detail = err.Error()
 	}

cmd/xl-v1-healing.go

@@ -205,6 +205,10 @@ func healBucketMetadata(xl xlObjects, bucket string, dryRun bool) (
 		reqInfo := &logger.ReqInfo{BucketName: bucket}
 		ctx := logger.SetReqInfo(context.Background(), reqInfo)
 		result, healErr := xl.HealObject(ctx, minioMetaBucket, metaPath, dryRun)
+		// If object is not found, skip the file.
+		if isErrObjectNotFound(healErr) {
+			return nil
+		}
 		if healErr != nil {
 			return healErr
 		}
@@ -604,13 +608,6 @@ func (xl xlObjects) healObjectDir(ctx context.Context, bucket, object string, dr
 // and later the disk comes back up again, heal on the object
 // should delete it.
 func (xl xlObjects) HealObject(ctx context.Context, bucket, object string, dryRun bool) (hr madmin.HealResultItem, err error) {
-	defer func() {
-		// If object is not found, ignore the error.
-		if isErrObjectNotFound(err) {
-			err = nil
-		}
-	}()
-
 	// Create context that also contains information about the object and bucket.
 	// The top level handler might not have this information.
 	reqInfo := logger.GetReqInfo(ctx)