github.com/MetalBlockchain/metalgo@v1.11.9/vms/proposervm/state_summary.go (about)

     1  // Copyright (C) 2019-2024, Ava Labs, Inc. All rights reserved.
     2  // See the file LICENSE for licensing terms.
     3  
     4  package proposervm
     5  
     6  import (
     7  	"context"
     8  
     9  	"github.com/MetalBlockchain/metalgo/snow/engine/snowman/block"
    10  	"github.com/MetalBlockchain/metalgo/vms/proposervm/summary"
    11  )
    12  
    13  var _ block.StateSummary = (*stateSummary)(nil)
    14  
    15  // stateSummary implements block.StateSummary by layering three objects:
    16  //
    17  //  1. [statelessSummary] carries all summary marshallable content along with
    18  //     data immediately retrievable from it.
    19  //  2. [innerSummary] reports the height of the summary as well as notifying the
    20  //     inner vm of the summary's acceptance.
    21  //  3. [block] is used to update the proposervm's last accepted block upon
    22  //     Accept.
    23  //
    24  // Note: summary.StatelessSummary contains the data to build both [innerSummary]
    25  // and [block].
    26  type stateSummary struct {
    27  	summary.StateSummary
    28  
    29  	// inner summary, retrieved via Parse
    30  	innerSummary block.StateSummary
    31  
    32  	// block associated with the summary
    33  	block PostForkBlock
    34  
    35  	vm *VM
    36  }
    37  
    38  func (s *stateSummary) Height() uint64 {
    39  	return s.innerSummary.Height()
    40  }
    41  
    42  func (s *stateSummary) Accept(ctx context.Context) (block.StateSyncMode, error) {
    43  	// If we have already synced up to or past this state summary, we do not
    44  	// want to sync to it.
    45  	if s.vm.lastAcceptedHeight >= s.Height() {
    46  		return block.StateSyncSkipped, nil
    47  	}
    48  
    49  	// set fork height first, before accepting proposerVM full block
    50  	// which updates height index (among other indices)
    51  	if err := s.vm.State.SetForkHeight(s.StateSummary.ForkHeight()); err != nil {
    52  		return block.StateSyncSkipped, err
    53  	}
    54  
    55  	// We store the full proposerVM block associated with the summary
    56  	// and update height index with it, so that state sync could resume
    57  	// after a shutdown.
    58  	if err := s.block.acceptOuterBlk(); err != nil {
    59  		return block.StateSyncSkipped, err
    60  	}
    61  
    62  	// innerSummary.Accept may fail with the proposerVM block and index already
    63  	// updated. The error would be treated as fatal and the chain would then be
    64  	// repaired upon the VM restart.
    65  	return s.innerSummary.Accept(ctx)
    66  }