interna/era,cmd: simplify era interace, fix era.ReadDir, fix lints

cmd/geth/chaincmd.go

@@ -20,6 +20,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -517,19 +518,21 @@ func importHistory(ctx *cli.Context) error {
 		network = networks[0]
 	}
 
-	format := ctx.String(utils.EraFormatFlag.Name)
+	var (
+		format = ctx.String(utils.EraFormatFlag.Name)
+		from   func(era.ReadAtSeekCloser) (era.Era, error)
+	)
 	switch format {
 	case "era1", "era":
-		if err := utils.ImportHistory(chain, dir, network, onedb.From, onedb.NewIterator); err != nil {
+		from = onedb.From
-			return err
-		}
 	case "erae":
-		if err := utils.ImportHistory(chain, dir, network, execdb.From, execdb.NewIterator); err != nil {
+		from = execdb.From
-			return err
-		}
 	default:
 		return fmt.Errorf("unknown --era.format %q (expected 'era1' or 'erae')", format)
 	}
+	if err := utils.ImportHistory(chain, dir, network, from); err != nil {
+		return err
+	}
 
 	fmt.Printf("Import done in %v\n", time.Since(start))
 	return nil
@@ -562,19 +565,24 @@ func exportHistory(ctx *cli.Context) error {
 		utils.Fatalf("Export error: block number %d larger than head block %d\n", uint64(last), head.Number.Uint64())
 	}
 
-	format := ctx.String(utils.EraFormatFlag.Get(ctx))
+	var (
+		format     = ctx.String(utils.EraFormatFlag.Get(ctx))
+		filename   func(network string, epoch int, root common.Hash) string
+		newBuilder func(w io.Writer) era.Builder
+	)
 	switch format {
 	case "era1", "era":
-		if err := utils.ExportHistory(chain, dir, uint64(first), uint64(last), uint64(era.MaxSize), onedb.NewBuilder, onedb.Filename); err != nil {
+		newBuilder = func(w io.Writer) era.Builder { return onedb.NewBuilder(w) }
-			utils.Fatalf("Export error: %v\n", err)
+		filename = func(network string, epoch int, root common.Hash) string { return onedb.Filename(network, epoch, root) }
-		}
 	case "erae":
-		if err := utils.ExportHistory(chain, dir, uint64(first), uint64(last), uint64(era.MaxSize), execdb.NewBuilder, execdb.Filename); err != nil {
+		newBuilder = func(w io.Writer) era.Builder { return execdb.NewBuilder(w) }
-			utils.Fatalf("Export error: %v\n", err)
+		filename = func(network string, epoch int, root common.Hash) string { return execdb.Filename(network, epoch, root) }
-		}
 	default:
 		return fmt.Errorf("unknown archive format %q (use 'era1' or 'erae')", format)
 	}
+	if err := utils.ExportHistory(chain, dir, uint64(first), uint64(last), uint64(era.MaxSize), newBuilder, filename); err != nil {
+		utils.Fatalf("Export error: %v\n", err)
+	}
 
 	fmt.Printf("Export done in %v\n", time.Since(start))
 	return nil

cmd/utils/cmd.go

@@ -253,7 +253,7 @@ func readList(filename string) ([]string, error) {
 // ImportHistory imports Era1 files containing historical block information,
 // starting from genesis. The assumption is held that the provided chain
 // segment in Era1 file should all be canonical and verified.
-func ImportHistory(chain *core.BlockChain, dir string, network string, from era.FromFn, iterator era.NewIteratorFn) error {
+func ImportHistory(chain *core.BlockChain, dir string, network string, from func(f era.ReadAtSeekCloser) (era.Era, error)) error {
 	if chain.CurrentSnapBlock().Number.BitLen() != 0 {
 		return errors.New("history import only supported when starting from genesis")
 	}
@@ -305,7 +305,7 @@ func ImportHistory(chain *core.BlockChain, dir string, network string, from era.
 			if err != nil {
 				return fmt.Errorf("error opening era: %w", err)
 			}
-			it, err := iterator(e)
+			it, err := e.Iterator()
 			if err != nil {
 				return fmt.Errorf("error creating iterator: %w", err)
 			}
@@ -417,7 +417,7 @@ func ExportAppendChain(blockchain *core.BlockChain, fn string, first uint64, las
 
 // ExportHistory exports blockchain history into the specified directory,
 // following the Era format.
-func ExportHistory(bc *core.BlockChain, dir string, first, last, step uint64, builderfn era.NewBuilderFn, filename era.FilenameFn) error {
+func ExportHistory(bc *core.BlockChain, dir string, first, last, step uint64, newBuilder func(io.Writer) era.Builder, filename func(network string, epoch int, root common.Hash) string) error {
 	log.Info("Exporting blockchain history", "dir", dir)
 	if head := bc.CurrentBlock().Number.Uint64(); head < last {
 		log.Warn("Last block beyond head, setting last = head", "head", head, "last", last)
@@ -455,7 +455,7 @@ func ExportHistory(bc *core.BlockChain, dir string, first, last, step uint64, bu
 			}
 			defer fh.Close()
 
-			bldr := builderfn(fh)
+			bldr := newBuilder(fh)
 
 			for j := uint64(0); j < step && batch+j <= last; j++ {
 				n := batch + j

cmd/utils/history_test.go

@@ -32,6 +32,7 @@ import (
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/internal/era"
 	"github.com/ethereum/go-ethereum/internal/era/onedb"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/trie"
@@ -89,7 +90,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 	dir := t.TempDir()
 
 	// Export history to temp directory.
-	if err := ExportHistory(chain, dir, 0, count, step); err != nil {
+	if err := ExportHistory(chain, dir, 0, count, step, onedb.NewBuilder, onedb.Filename); err != nil {
 		t.Fatalf("error exporting history: %v", err)
 	}
 
@@ -101,7 +102,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 	checksums := strings.Split(string(b), "\n")
 
 	// Verify each Era.
-	entries, _ := onedb.ReadDir(dir, "mainnet")
+	entries, _ := era.ReadDir(dir, "mainnet")
 	for i, filename := range entries {
 		func() {
 			f, err := os.Open(filepath.Join(dir, filename))
@@ -170,7 +171,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unable to initialize chain: %v", err)
 	}
-	if err := ImportHistory(imported, dir, "mainnet"); err != nil {
+	if err := ImportHistory(imported, dir, "mainnet", onedb.From); err != nil {
 		t.Fatalf("failed to import chain: %v", err)
 	}
 	if have, want := imported.CurrentHeader(), chain.CurrentHeader(); have.Hash() != want.Hash() {

internal/era/era.go

@@ -59,45 +59,34 @@ type Era interface {
 	Close() error
 	Start() uint64
 	Count() uint64
+	Iterator() (Iterator, error)
 	GetBlockByNumber(num uint64) (*types.Block, error)
 	GetRawBodyByNumber(num uint64) ([]byte, error)
 	GetRawReceiptsByNumber(num uint64) ([]byte, error)
 }
 
-// NewBuilderFn defines a function type for creating a new Builder.
-type NewBuilderFn func(w io.Writer) Builder
-
-// FilenameFn defines a function type for generating a filename based on network, epoch, and root hash.
-type FilenameFn func(network string, epoch int, root common.Hash) string
-
-// FromFn defines a function type for creating an Era from a ReadAtSeekCloser.
-type FromFn func(f ReadAtSeekCloser) (Era, error)
-
-// NewIteratorFn defines a function type for creating a new Iterator from an Era.
-type NewIteratorFn func(e Era) (Iterator, error)
-
 // ReadDir reads all the era1 files in a directory for a given network.
 // Format: <network>-<epoch>-<hexroot>.erae or <network>-<epoch>-<hexroot>.era1
 func ReadDir(dir, network string) ([]string, error) {
 	entries, err := os.ReadDir(dir)
-	var directoryExtension string
+
 	if err != nil {
 		return nil, fmt.Errorf("error reading directory %s: %w", dir, err)
 	}
 	var (
-		next = uint64(0)
+		next    = uint64(0)
-		eras []string
+		eras    []string
+		dirType string
 	)
-	for i, entry := range entries {
+	fmt.Println("entries", entries)
-		fileExtension := path.Ext(entry.Name())
+	for _, entry := range entries {
-		if i == 0 {
+		ext := path.Ext(entry.Name())
-			directoryExtension = fileExtension
+		if ext != ".erae" && ext != ".era1" {
-		} else if directoryExtension != fileExtension {
-			return nil, fmt.Errorf("directory %s contains mixed era file formats", dir)
-		}
-		if fileExtension != ".erae" || fileExtension != ".era1" {
 			continue
 		}
+		if dirType == "" {
+			dirType = ext
+		}
 		parts := strings.Split(entry.Name(), "-")
 		if len(parts) != 3 || parts[0] != network {
 			// Invalid era1 filename, skip.
@@ -108,6 +97,9 @@ func ReadDir(dir, network string) ([]string, error) {
 		} else if epoch != next {
 			return nil, fmt.Errorf("missing epoch %d", next)
 		}
+		if dirType != ext {
+			return nil, fmt.Errorf("directory %s contains mixed era file formats: want %s, have %s", dir, dirType, ext)
+		}
 		next += 1
 		eras = append(eras, entry.Name())
 	}

internal/era/execdb/builder.go

@@ -89,7 +89,6 @@ type Builder struct {
 	written       uint64
 	expectsProofs bool
 	isPreMerge    bool
-	numPreMerge   int      // number of pre-merge blocks
 	finalTD       *big.Int // final total difficulty, used for pre-merge and merge straddling files
 }
 

internal/era/execdb/reader.go

@@ -88,6 +88,11 @@ func (e *Era) Count() uint64 {
 	return e.m.count
 }
 
+// Iterator returns an iterator over the era file.
+func (e *Era) Iterator() (era.Iterator, error) {
+	return NewIterator(e)
+}
+
 // GetBlockByNumber retrieves the block if present within the era file.
 func (e *Era) GetBlockByNumber(blockNum uint64) (*types.Block, error) {
 	h, err := e.GetHeader(blockNum)

internal/era/onedb/reader.go

@@ -81,6 +81,11 @@ func (e *Era) Close() error {
 	return e.f.Close()
 }
 
+// Iterator returns an iterator over the era file.
+func (e *Era) Iterator() (era.Iterator, error) {
+	return NewIterator(e)
+}
+
 // GetBlockByNumber returns the block for the given block number.
 func (e *Era) GetBlockByNumber(num uint64) (*types.Block, error) {
 	if e.m.start > num || e.m.start+e.m.count <= num {

internal/era/proof.go

@@ -110,7 +110,3 @@ func (p *BlockProofHistoricalSummariesDeneb) EncodeRLP(w io.Writer) error {
 
 // Variant returns the variant type of the BlockProofHistoricalSummariesDeneb.
 func (*BlockProofHistoricalSummariesDeneb) Variant() variant { return proofDeneb }
-
-func variantOf(p Proof) variant {
-	return p.Variant()
-}