Fix EC rebuild shard detection (#8265)

Fix EC rebuild shard counting

weed/server/volume_grpc_erasure_coding.go

@@ -7,6 +7,7 @@ import (
 	"math"
 	"os"
 	"path"
+	"strconv"
 	"strings"
 	"time"
 
@@ -338,13 +339,30 @@ func checkEcVolumeStatus(bName string, location *storage.DiskLocation) (hasEcxFi
 			hasIdxFile = true
 			continue
 		}
-		if strings.HasPrefix(fileInfo.Name(), bName+".ec") {
+		if isEcDataShardFile(fileInfo.Name(), bName) {
 			existingShardCount++
 		}
 	}
 	return hasEcxFile, hasIdxFile, existingShardCount, nil
 }
 
+func isEcDataShardFile(fileName, baseName string) bool {
+	const ecDataShardSuffixLen = 2 // ".ecNN"
+	prefix := baseName + ".ec"
+	if !strings.HasPrefix(fileName, prefix) {
+		return false
+	}
+	suffix := strings.TrimPrefix(fileName, prefix)
+	if len(suffix) != ecDataShardSuffixLen {
+		return false
+	}
+	shardId, err := strconv.Atoi(suffix)
+	if err != nil {
+		return false
+	}
+	return shardId >= 0 && shardId < erasure_coding.MaxShardCount
+}
+
 func (vs *VolumeServer) VolumeEcShardsMount(ctx context.Context, req *volume_server_pb.VolumeEcShardsMountRequest) (*volume_server_pb.VolumeEcShardsMountResponse, error) {
 
 	glog.V(0).Infof("VolumeEcShardsMount: %v", req)

weed/server/volume_grpc_erasure_coding_test.go

@@ -0,0 +1,57 @@
+package weed_server
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/storage"
+)
+
+func TestCheckEcVolumeStatusCountOnlyDataShards(t *testing.T) {
+	tempDir := t.TempDir()
+	dataDir := filepath.Join(tempDir, "data")
+	idxDir := filepath.Join(tempDir, "idx")
+	if err := os.MkdirAll(dataDir, 0o755); err != nil {
+		t.Fatalf("mkdir data dir: %v", err)
+	}
+	if err := os.MkdirAll(idxDir, 0o755); err != nil {
+		t.Fatalf("mkdir idx dir: %v", err)
+	}
+
+	baseName := "7"
+	filesToCreate := []string{
+		filepath.Join(dataDir, baseName+".ec00"),
+		filepath.Join(dataDir, baseName+".ec09"),
+		filepath.Join(dataDir, baseName+".ec13"),
+		filepath.Join(idxDir, baseName+".ecx"),
+		filepath.Join(idxDir, baseName+".ecj"),
+		filepath.Join(idxDir, baseName+".idx"),
+	}
+	for _, fileName := range filesToCreate {
+		if err := os.WriteFile(fileName, []byte("x"), 0o644); err != nil {
+			t.Fatalf("create %s: %v", fileName, err)
+		}
+	}
+
+	location := &storage.DiskLocation{
+		Directory:    dataDir,
+		IdxDirectory: idxDir,
+	}
+
+	hasEcxFile, hasIdxFile, shardCount, err := checkEcVolumeStatus(baseName, location)
+	if err != nil {
+		t.Fatalf("checkEcVolumeStatus: %v", err)
+	}
+
+	if !hasEcxFile {
+		t.Fatalf("expected hasEcxFile=true")
+	}
+	if !hasIdxFile {
+		t.Fatalf("expected hasIdxFile=true")
+	}
+	if shardCount != 3 {
+		t.Fatalf("expected shardCount=3, got %d", shardCount)
+	}
+}
+