Added a few more comments to mtredisalize and unexport a few symbols.

cmd/mtredisalize/backend.go

@@ -5,24 +5,39 @@
 package main
 
 type (
+	// Block is the essential transfer unit from to the database.
+	// Key is the serialized spatial position.
+	// Data is the serialized from of the corresponding block data.
 	Block struct {
 		Key  []byte
 		Data []byte
 	}
 
+	// Session is a database session.
 	Session interface {
+		// Fetch fetches the block data for a given position.
 		Fetch(hash, key []byte) ([]byte, error)
+		// InTransaction returns true if a transaction is running.
 		InTransaction() bool
+		// Store stores a block with a given position and data.
 		Store(hash, key, value []byte) (bool, error)
+		// AllKeys returns all keys in the database.
 		AllKeys(hash []byte, done chan struct{}) (chan []byte, int, error)
+		// SpatialQuery performs a box query between the positions first and second.
 		SpatialQuery(hash, first, second []byte, done chan struct{}) (chan Block, error)
+		// BeginTransaction starts a transcation.
 		BeginTransaction() error
+		// CommitTransaction finishes a transaction.
 		CommitTransaction() error
+		// Close closes the database session.
 		Close() error
 	}
 
+	// Backend is interface representing a database.
 	Backend interface {
+		// NewSession opens a new session.
 		NewSession() (Session, error)
+		// Shutdown shuts down the database server.
 		Shutdown() error
 	}
 )

cmd/mtredisalize/changetracker.go

@@ -22,16 +22,16 @@ type quantizedXZ struct {
 	X, Z int16
 }
 
-type ChangeTracker struct {
+type changeTracker struct {
 	changes map[quantizedXZ]bool
 	mutex   sync.Mutex
 }
 
-func NewChangeTracker() *ChangeTracker {
+func newChangeTracker() *changeTracker {
-	return &ChangeTracker{changes: make(map[quantizedXZ]bool)}
+	return &changeTracker{changes: make(map[quantizedXZ]bool)}
 }
 
-func (ct *ChangeTracker) BlockChanged(coord common.Coord) {
+func (ct *changeTracker) BlockChanged(coord common.Coord) {
 	ct.mutex.Lock()
 	ct.changes[quantizedXZ{
 		X: coord.X / quantizationFactor,
@@ -39,7 +39,7 @@ func (ct *ChangeTracker) BlockChanged(coord common.Coord) {
 	ct.mutex.Unlock()
 }
 
-func (ct *ChangeTracker) FlushChanges(url string) {
+func (ct *changeTracker) FlushChanges(url string) {
 	var oldChanges map[quantizedXZ]bool
 	ct.mutex.Lock()
 	if len(ct.changes) > 0 {

cmd/mtredisalize/leveldb.go

@@ -21,7 +21,7 @@ type LevelDBBackend struct {
 	encoder     common.KeyTranscoder
 	decoder     common.KeyTranscoder
 
-	changeTracker *ChangeTracker
+	changeTracker *changeTracker
 	mutex         sync.RWMutex
 }
 
@@ -32,7 +32,7 @@ type LevelDBSession struct {
 
 func NewLeveDBBackend(
 	path string,
-	changeTracker *ChangeTracker,
+	changeTracker *changeTracker,
 	interleaved bool,
 	cacheSize int) (ldb *LevelDBBackend, err error) {
 

cmd/mtredisalize/main.go

@@ -19,8 +19,8 @@ import (
 
 const (
 	defaultMaxBulkStringSize = 32 * 1024 * 1024
-	GCDuration               = "24h"
+	defaultGCDuration        = "24h"
-	ChangeDuration           = "30s"
+	defaultChangeDuration    = "30s"
 )
 
 func usage() {
@@ -55,9 +55,9 @@ func main() {
 	flag.BoolVar(&interleaved,
 		"interleaved", false, "Backend stores key in interleaved form.")
 	flag.StringVar(&gcDuration,
-		"gc-duration", GCDuration, "Duration between forced GCs.")
+		"gc-duration", defaultGCDuration, "Duration between forced GCs.")
 	flag.StringVar(&changeDuration,
-		"change-duration", ChangeDuration, "Duration to aggregate changes.")
+		"change-duration", defaultChangeDuration, "Duration to aggregate changes.")
 	flag.StringVar(&changeURL, "change-url", "", "URL to send changes to.")
 	flag.Int64Var(&maxBulkStringSize, "max-bulk-string-size", defaultMaxBulkStringSize,
 		"max size of a bulk string to be accepted as input (in bytes).")
@@ -76,7 +76,7 @@ func main() {
 		backend       Backend
 		gcDur         time.Duration
 		chDur         time.Duration
-		changeTracker *ChangeTracker
+		changeTracker *changeTracker
 	)
 
 	if gcDur, err = time.ParseDuration(gcDuration); err != nil {
@@ -94,7 +94,7 @@ func main() {
 			log.Fatal(err)
 		}
 		changeChan = time.Tick(chDur)
-		changeTracker = NewChangeTracker()
+		changeTracker = newChangeTracker()
 	} else {
 		// We will never receive ticks on this.
 		changeChan = make(<-chan time.Time)

cmd/mtredisalize/sqlite.go

@@ -30,7 +30,7 @@ type SqliteBackend struct {
 	db            *sql.DB
 	encoder       common.KeyEncoder
 	decoder       common.KeyDecoder
-	changeTracker *ChangeTracker
+	changeTracker *changeTracker
 	interleaved   bool
 	coverage      *common.Coverage3D
 	existsStmt    *sql.Stmt
@@ -62,7 +62,7 @@ func (ss *SqliteSession) Close() error {
 
 func NewSqliteBackend(
 	path string,
-	changeTracker *ChangeTracker, interleaved bool) (sqlb *SqliteBackend, err error) {
+	changeTracker *changeTracker, interleaved bool) (sqlb *SqliteBackend, err error) {
 
 	res := SqliteBackend{interleaved: interleaved, changeTracker: changeTracker}