exp/lighthorizon: Restructure index package into sensible sub-packages

exp/lighthorizon/index/backend/backend.go

@@ -0,0 +1,14 @@
+package index
+
+import types "github.com/stellar/go/exp/lighthorizon/index/types"
+
+// TODO: Use a more standardized filesystem-style backend, so we can re-use
+// code
+type Backend interface {
+	Flush(map[string]types.NamedIndices) error
+	FlushAccounts([]string) error
+	Read(account string) (types.NamedIndices, error)
+	ReadAccounts() ([]string, error)
+	FlushTransactions(map[string]*types.TrieIndex) error
+	ReadTransactions(prefix string) (*types.TrieIndex, error)
+}

exp/lighthorizon/index/file.go → exp/lighthorizon/index/backend/file.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 	"github.com/stellar/go/support/errors"
 	"github.com/stellar/go/support/log"
 )
@@ -17,22 +18,14 @@ type FileBackend struct {
 	parallel uint32
 }
 
-func NewFileStore(dir string, parallel uint32) (Store, error) {
-	backend, err := NewFileBackend(dir, parallel)
-	if err != nil {
-		return nil, err
-	}
-	return NewStore(backend)
-}
-
 func NewFileBackend(dir string, parallel uint32) (*FileBackend, error) {
 	return &FileBackend{
 		dir:      dir,
 		parallel: parallel,
 	}, nil
 }
 
-func (s *FileBackend) Flush(indexes map[string]map[string]*CheckpointIndex) error {
+func (s *FileBackend) Flush(indexes map[string]types.NamedIndices) error {
 	return parallelFlush(s.parallel, indexes, s.writeBatch)
 }
 
@@ -88,7 +81,7 @@ func (s *FileBackend) writeBatch(b *batch) error {
 	return nil
 }
 
-func (s *FileBackend) FlushTransactions(indexes map[string]*TrieIndex) error {
+func (s *FileBackend) FlushTransactions(indexes map[string]*types.TrieIndex) error {
 	// TODO: Parallelize this
 	for key, index := range indexes {
 		path := filepath.Join(s.dir, "tx", key)
@@ -125,7 +118,7 @@ func (s *FileBackend) FlushTransactions(indexes map[string]*TrieIndex) error {
 	return nil
 }
 
-func (s *FileBackend) Read(account string) (map[string]*CheckpointIndex, error) {
+func (s *FileBackend) Read(account string) (types.NamedIndices, error) {
 	log.Debugf("Opening index: %s", account)
 	b, err := os.Open(filepath.Join(s.dir, account[:3], account))
 	if err != nil {
@@ -185,7 +178,7 @@ func (s *FileBackend) ReadAccounts() ([]string, error) {
 	return accounts, nil
 }
 
-func (s *FileBackend) ReadTransactions(prefix string) (*TrieIndex, error) {
+func (s *FileBackend) ReadTransactions(prefix string) (*types.TrieIndex, error) {
 	log.Debugf("Opening index: %s", prefix)
 	b, err := os.Open(filepath.Join(s.dir, "tx", prefix))
 	if err != nil {
@@ -198,7 +191,7 @@ func (s *FileBackend) ReadTransactions(prefix string) (*TrieIndex, error) {
 		return nil, os.ErrNotExist
 	}
 	defer zr.Close()
-	var index TrieIndex
+	var index types.TrieIndex
 	_, err = index.ReadFrom(zr)
 	if err != nil {
 		log.Errorf("Unable to parse %s: %v", prefix, err)

exp/lighthorizon/index/gzip.go → exp/lighthorizon/index/backend/gzip.go

@@ -4,9 +4,11 @@ import (
 	"bytes"
 	"compress/gzip"
 	"io"
+
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 )
 
-func writeGzippedTo(w io.Writer, indexes map[string]*CheckpointIndex) (int64, error) {
+func writeGzippedTo(w io.Writer, indexes types.NamedIndices) (int64, error) {
 	zw := gzip.NewWriter(w)
 
 	var n int64
@@ -28,12 +30,12 @@ func writeGzippedTo(w io.Writer, indexes map[string]*CheckpointIndex) (int64, er
 	return n, nil
 }
 
-func readGzippedFrom(r io.Reader) (map[string]*CheckpointIndex, int64, error) {
+func readGzippedFrom(r io.Reader) (types.NamedIndices, int64, error) {
 	zr, err := gzip.NewReader(r)
 	if err != nil {
 		return nil, 0, err
 	}
-	indexes := map[string]*CheckpointIndex{}
+	indexes := types.NamedIndices{}
 	var buf bytes.Buffer
 	var n int64
 	for {
@@ -45,7 +47,7 @@ func readGzippedFrom(r io.Reader) (map[string]*CheckpointIndex, int64, error) {
 			return nil, n, err
 		}
 
-		ind, err := NewCheckpointIndexFromBytes(buf.Bytes())
+		ind, err := types.NewCheckpointIndexFromBytes(buf.Bytes())
 		if err != nil {
 			return nil, n, err
 		}

exp/lighthorizon/index/gzip_test.go → exp/lighthorizon/index/backend/gzip_test.go

@@ -4,12 +4,13 @@ import (
 	"bytes"
 	"testing"
 
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 	"github.com/stretchr/testify/require"
 )
 
 func TestGzipWriteReadRoundtrip(t *testing.T) {
-	indexes := map[string]*CheckpointIndex{}
-	index := &CheckpointIndex{}
+	indexes := types.NamedIndices{}
+	index := &types.CheckpointIndex{}
 	index.SetActive(5)
 	indexes["A"] = index
 

exp/lighthorizon/index/parallel_flush.go → exp/lighthorizon/index/backend/parallel_flush.go

@@ -5,17 +5,18 @@ import (
 	"sync/atomic"
 	"time"
 
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 	"github.com/stellar/go/support/log"
 )
 
 type batch struct {
 	account string
-	indexes map[string]*CheckpointIndex
+	indexes types.NamedIndices
 }
 
 type flushBatch func(b *batch) error
 
-func parallelFlush(parallel uint32, allIndexes map[string]map[string]*CheckpointIndex, f flushBatch) error {
+func parallelFlush(parallel uint32, allIndexes map[string]types.NamedIndices, f flushBatch) error {
 	var wg sync.WaitGroup
 
 	batches := make(chan *batch, parallel)

exp/lighthorizon/index/s3.go → exp/lighthorizon/index/backend/s3.go

@@ -15,6 +15,8 @@ import (
 	"github.com/aws/aws-sdk-go/service/s3/s3manager"
 	"github.com/stellar/go/support/errors"
 	"github.com/stellar/go/support/log"
+
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 )
 
 const BUCKET = "horizon-index"
@@ -27,14 +29,6 @@ type S3Backend struct {
 	prefix     string
 }
 
-func NewS3Store(awsConfig *aws.Config, prefix string, parallel uint32) (Store, error) {
-	backend, err := NewS3Backend(awsConfig, prefix, parallel)
-	if err != nil {
-		return nil, err
-	}
-	return NewStore(backend)
-}
-
 func NewS3Backend(awsConfig *aws.Config, prefix string, parallel uint32) (*S3Backend, error) {
 	s3Session, err := session.NewSession(awsConfig)
 	if err != nil {
@@ -72,7 +66,7 @@ func (s *S3Backend) FlushAccounts(accounts []string) error {
 	return nil
 }
 
-func (s *S3Backend) Flush(indexes map[string]map[string]*CheckpointIndex) error {
+func (s *S3Backend) Flush(indexes map[string]types.NamedIndices) error {
 	return parallelFlush(s.parallel, indexes, s.writeBatch)
 }
 
@@ -98,7 +92,7 @@ func (s *S3Backend) writeBatch(b *batch) error {
 	return nil
 }
 
-func (s *S3Backend) FlushTransactions(indexes map[string]*TrieIndex) error {
+func (s *S3Backend) FlushTransactions(indexes map[string]*types.TrieIndex) error {
 	// TODO: Parallelize this
 	var buf bytes.Buffer
 	for key, index := range indexes {
@@ -156,7 +150,7 @@ func (s *S3Backend) path(account string) string {
 	return filepath.Join(s.prefix, account[:10], account)
 }
 
-func (s *S3Backend) Read(account string) (map[string]*CheckpointIndex, error) {
+func (s *S3Backend) Read(account string) (types.NamedIndices, error) {
 	// Check if index exists in S3
 	log.Debugf("Downloading index: %s", account)
 	var err error
@@ -179,7 +173,7 @@ func (s *S3Backend) Read(account string) (map[string]*CheckpointIndex, error) {
 		if n == 0 {
 			return nil, os.ErrNotExist
 		}
-		var indexes map[string]*CheckpointIndex
+		var indexes map[string]*types.CheckpointIndex
 		indexes, _, err = readGzippedFrom(bytes.NewReader(b.Bytes()))
 		if err != nil {
 			log.Errorf("Unable to parse %s: %v", account, err)
@@ -191,7 +185,7 @@ func (s *S3Backend) Read(account string) (map[string]*CheckpointIndex, error) {
 	return nil, err
 }
 
-func (s *S3Backend) ReadTransactions(prefix string) (*TrieIndex, error) {
+func (s *S3Backend) ReadTransactions(prefix string) (*types.TrieIndex, error) {
 	// Check if index exists in S3
 	log.Debugf("Downloading index: %s", prefix)
 	b := &aws.WriteAtBuffer{}
@@ -216,7 +210,7 @@ func (s *S3Backend) ReadTransactions(prefix string) (*TrieIndex, error) {
 	}
 	defer zr.Close()
 
-	var index TrieIndex
+	var index types.TrieIndex
 	_, err = index.ReadFrom(zr)
 	if err != nil {
 		log.Errorf("Unable to parse %s: %v", prefix, err)

exp/lighthorizon/index/cmd/batch/reduce/main.go

@@ -10,6 +10,7 @@ import (
 	"sync"
 
 	"github.com/stellar/go/exp/lighthorizon/index"
+	types "github.com/stellar/go/exp/lighthorizon/index/types"
 	"github.com/stellar/go/support/errors"
 	"github.com/stellar/go/support/log"
 )
@@ -337,7 +338,7 @@ func (cfg *ReduceConfig) shouldProcessTx(txPrefix byte, routineIndex uint32) boo
 
 // For every index that exists in `dest`, finds the corresponding index in
 // `source` and merges it into `dest`'s version.
-func mergeIndices(dest, source map[string]*index.CheckpointIndex) error {
+func mergeIndices(dest, source map[string]*types.CheckpointIndex) error {
 	for name, index := range dest {
 		// The source doesn't contain this particular index.
 		//

exp/lighthorizon/index/connect.go

@@ -6,6 +6,8 @@ import (
 	"path/filepath"
 
 	"github.com/aws/aws-sdk-go/aws"
+
+	backend "github.com/stellar/go/exp/lighthorizon/index/backend"
 )
 
 func Connect(backendUrl string) (Store, error) {
@@ -31,3 +33,19 @@ func Connect(backendUrl string) (Store, error) {
 			parsed.Scheme, backendUrl)
 	}
 }
+
+func NewFileStore(dir string, parallel uint32) (Store, error) {
+	backend, err := backend.NewFileBackend(dir, parallel)
+	if err != nil {
+		return nil, err
+	}
+	return NewStore(backend)
+}
+
+func NewS3Store(awsConfig *aws.Config, prefix string, parallel uint32) (Store, error) {
+	backend, err := backend.NewS3Backend(awsConfig, prefix, parallel)
+	if err != nil {
+		return nil, err
+	}
+	return NewStore(backend)
+}