Add the ability to disable persistence

gdstore.go

@@ -19,8 +19,19 @@ type GDStore struct {
 	//
 	// In contrast, writing to the file without a buffer is slower, but more reliable if your
 	// application is prone to suddenly crashing
+	//
+	// Defaults to false
 	useBuffer bool
 
+	// persistence lets the user set whether to persist data to the file or not. Meant to be used for testing without
+	// having to clean up the file.
+	//
+	// (default) If set to true, data is available both in-memory and persisted to the file found at FilePath.
+	// If set to false, data is available only in-memory, and upon destruction, all data will be lost.
+	//
+	// Defaults to true
+	persistence bool
+
 	file   *os.File
 	writer *bufio.Writer
 	data   map[string][]byte
@@ -30,8 +41,9 @@ type GDStore struct {
 // New creates a new GDStore
 func New(filePath string) *GDStore {
 	store := &GDStore{
-		FilePath: filePath,
-		data:     make(map[string][]byte),
+		FilePath:    filePath,
+		data:        make(map[string][]byte),
+		persistence: true,
 	}
 	err := store.loadFromDisk()
 	if err != nil {
@@ -48,6 +60,16 @@ func (store *GDStore) WithBuffer(useBuffer bool) *GDStore {
 	return store
 }
 
+// WithPersistence sets GDStore's persistence parameter to the value passed as parameter
+//
+// The ability to set persistence to false is there mainly for testing purposes
+//
+// The default value for persistence is true
+func (store *GDStore) WithPersistence(persistence bool) *GDStore {
+	store.persistence = persistence
+	return store
+}
+
 // Get returns the value of a key as well as a bool that indicates whether an entry exists for that key.
 //
 // The bool is particularly useful if you want to differentiate between a key that has a nil value, and a
@@ -60,7 +82,7 @@ func (store *GDStore) Get(key string) (value []byte, ok bool) {
 // GetString does the same thing as Get, but converts the value to a string
 func (store *GDStore) GetString(key string) (valueAsString string, ok bool) {
 	var value []byte
-	value, ok = store.data[key]
+	value, ok = store.Get(key)
 	if ok {
 		valueAsString = string(value)
 	}

persistence.go

@@ -2,7 +2,6 @@ package gdstore
 
 import (
 	"bufio"
-	"errors"
 	"fmt"
 	"os"
 )
@@ -41,17 +40,20 @@ func (store *GDStore) Flush() error {
 func (store *GDStore) Consolidate() error {
 	store.mux.Lock()
 	defer store.mux.Unlock()
+	if !store.persistence {
+		return nil
+	}
 	// Close the file because we need to rename it
 	store.Close()
 	// Back up the old file before doing the consolidation
 	err := os.Rename(store.FilePath, fmt.Sprintf("%s.bak", store.FilePath))
 	if err != nil {
-		return errors.New(fmt.Sprintf("unable to rename %s to %s.bak during consolidation: %s", store.FilePath, store.FilePath, err.Error()))
+		return fmt.Errorf("unable to rename %s to %s.bak during consolidation: %s", store.FilePath, store.FilePath, err.Error())
 	}
 	// Create a new empty file
 	file, err := os.Create(store.FilePath)
 	if err != nil {
-		return errors.New(fmt.Sprintf("unable to create new empty file at %s during consolidation: %s", store.FilePath, err.Error()))
+		return fmt.Errorf("unable to create new empty file at %s during consolidation: %s", store.FilePath, err.Error())
 	}
 	err = file.Close()
 	if err != nil {
@@ -66,6 +68,9 @@ func (store *GDStore) Consolidate() error {
 // loadFromDisk loads the store from the disk and consolidates the entries, or creates an empty file if there is no file
 func (store *GDStore) loadFromDisk() error {
 	store.data = make(map[string][]byte)
+	if !store.persistence {
+		return nil
+	}
 	file, err := os.Open(store.FilePath)
 	if err != nil {
 		// Check if the file exists, if it doesn't, then create it and return.
@@ -79,7 +84,6 @@ func (store *GDStore) loadFromDisk() error {
 			return err
 		}
 	}
-
 	// File doesn't exist, so we need to read it.
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {
@@ -104,6 +108,9 @@ func (store *GDStore) appendEntryToFile(entry *Entry) error {
 
 // appendEntriesToFile appends a list of entries to the store's file
 func (store *GDStore) appendEntriesToFile(entries []*Entry) (err error) {
+	if !store.persistence {
+		return
+	}
 	if store.file == nil {
 		store.file, err = os.OpenFile(store.FilePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
 		if err != nil {