fix(ec): full-teardown delete so cluster cleanup wipes a whole generation

The pre-encode cluster sweep deleted only the listed canonical shards on
remote nodes, leaving index/sidecar (and, on builds with versioned
generations, those too) behind. Add a full_teardown flag to
VolumeEcShardsDelete that evicts the volume and wipes every EC artifact for
it on every disk via removeStaleEcArtifacts; the shell and worker pre-encode
cleanup paths set it. Other delete callers (balance/decode/repair) are
unchanged.

weed/pb/volume_server.proto

@@ -452,6 +452,7 @@ message VolumeEcShardsDeleteRequest {
     uint32 volume_id = 1;
     string collection = 2;
     repeated uint32 shard_ids = 3;
+    bool full_teardown = 4; // pre-encode cleanup: wipe every EC artifact + generation for this volume, not just shard_ids
 }
 message VolumeEcShardsDeleteResponse {
 }

weed/pb/volume_server_pb/volume_server.pb.go

@@ -3605,6 +3605,7 @@ type VolumeEcShardsDeleteRequest struct {
 	VolumeId      uint32                 `protobuf:"varint,1,opt,name=volume_id,json=volumeId,proto3" json:"volume_id,omitempty"`
 	Collection    string                 `protobuf:"bytes,2,opt,name=collection,proto3" json:"collection,omitempty"`
 	ShardIds      []uint32               `protobuf:"varint,3,rep,packed,name=shard_ids,json=shardIds,proto3" json:"shard_ids,omitempty"`
+	FullTeardown  bool                   `protobuf:"varint,4,opt,name=full_teardown,json=fullTeardown,proto3" json:"full_teardown,omitempty"` // pre-encode cleanup: wipe every EC artifact + generation for this volume, not just shard_ids
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -3660,6 +3661,13 @@ func (x *VolumeEcShardsDeleteRequest) GetShardIds() []uint32 {
 	return nil
 }
 
+func (x *VolumeEcShardsDeleteRequest) GetFullTeardown() bool {
+	if x != nil {
+		return x.FullTeardown
+	}
+	return false
+}
+
 type VolumeEcShardsDeleteResponse struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
 	unknownFields protoimpl.UnknownFields
@@ -7244,13 +7252,14 @@ const file_volume_server_proto_rawDesc = "" +
 	"\rcopy_vif_file\x18\a \x01(\bR\vcopyVifFile\x12\x17\n" +
 	"\adisk_id\x18\b \x01(\rR\x06diskId\x12&\n" +
 	"\x0fcopy_ecsum_file\x18\t \x01(\bR\rcopyEcsumFile\"\x1c\n" +
-	"\x1aVolumeEcShardsCopyResponse\"w\n" +
+	"\x1aVolumeEcShardsCopyResponse\"\x9c\x01\n" +
 	"\x1bVolumeEcShardsDeleteRequest\x12\x1b\n" +
 	"\tvolume_id\x18\x01 \x01(\rR\bvolumeId\x12\x1e\n" +
 	"\n" +
 	"collection\x18\x02 \x01(\tR\n" +
 	"collection\x12\x1b\n" +
-	"\tshard_ids\x18\x03 \x03(\rR\bshardIds\"\x1e\n" +
+	"\tshard_ids\x18\x03 \x03(\rR\bshardIds\x12#\n" +
+	"\rfull_teardown\x18\x04 \x01(\bR\ffullTeardown\"\x1e\n" +
 	"\x1cVolumeEcShardsDeleteResponse\"\xa0\x01\n" +
 	"\x1aVolumeEcShardsMountRequest\x12\x1b\n" +
 	"\tvolume_id\x18\x01 \x01(\rR\bvolumeId\x12\x1e\n" +

weed/server/volume_grpc_erasure_coding.go

@@ -417,6 +417,23 @@ func (vs *VolumeServer) VolumeEcShardsDelete(ctx context.Context, req *volume_se
 
 	bName := erasure_coding.EcShardBaseFileName(req.Collection, int(req.VolumeId))
 
+	if req.FullTeardown {
+		// Pre-encode cleanup: evict the volume and wipe every EC artifact for it on
+		// every disk (the same teardown the generator does locally), not just the
+		// listed shards, so a remote node retains no stale generation that a fresh
+		// gen-0 copy would later collide with.
+		glog.V(0).Infof("ec volume %s full teardown", bName)
+		vs.store.UnloadEcVolume(needle.VolumeId(req.VolumeId))
+		for _, location := range vs.store.Locations {
+			dataBase := storage.VolumeFileName(location.Directory, req.Collection, int(req.VolumeId))
+			idxBase := storage.VolumeFileName(location.IdxDirectory, req.Collection, int(req.VolumeId))
+			if err := removeStaleEcArtifacts(dataBase, idxBase, erasure_coding.MaxShardCount); err != nil {
+				return nil, fmt.Errorf("full teardown of ec volume %d on %s: %w", req.VolumeId, location.Directory, err)
+			}
+		}
+		return &volume_server_pb.VolumeEcShardsDeleteResponse{}, nil
+	}
+
 	glog.V(0).Infof("ec volume %s shard delete %v", bName, req.ShardIds)
 
 	for diskId, location := range vs.store.Locations {

weed/shell/command_ec_common.go

@@ -550,9 +550,10 @@ func unmountAndDeleteEcShardsQuiet(grpcDialOption grpc.DialOption, collection st
 			return fmt.Errorf("unmount: %w", err)
 		}
 		if _, err := volumeServerClient.VolumeEcShardsDelete(context.Background(), &volume_server_pb.VolumeEcShardsDeleteRequest{
-			VolumeId:   uint32(volumeId),
-			Collection: collection,
-			ShardIds:   ids,
+			VolumeId:     uint32(volumeId),
+			Collection:   collection,
+			ShardIds:     ids,
+			FullTeardown: true,
 		}); err != nil {
 			return fmt.Errorf("delete: %w", err)
 		}

weed/worker/tasks/erasure_coding/ec_task.go

@@ -978,9 +978,10 @@ func unmountAndDeleteEcShards(
 				return fmt.Errorf("unmount: %w", err)
 			}
 			if _, err := client.VolumeEcShardsDelete(ctx, &volume_server_pb.VolumeEcShardsDeleteRequest{
-				VolumeId:   volumeID,
-				Collection: collection,
-				ShardIds:   shardIds,
+				VolumeId:     volumeID,
+				Collection:   collection,
+				ShardIds:     shardIds,
+				FullTeardown: true,
 			}); err != nil {
 				return fmt.Errorf("delete: %w", err)
 			}