add: LoadFontFromReader API

update: readme and history

README.md

@@ -27,7 +27,7 @@ func handle(w http.ResponseWriter, r *http.Request) {
 	session.Values["captcha"] = data.Text
 	session.Save(r, w)
 	// send image data to client
-	data.WriteTo(w)
+	data.WriteImage(w)
 }
 
 ```

captcha.go

@@ -2,6 +2,7 @@
 package captcha
 
 import (
+	"bytes"
 	"github.com/golang/freetype"
 	"github.com/golang/freetype/truetype"
 	"golang.org/x/image/font"
@@ -83,13 +84,23 @@ func init() {
 	ttfFont, _ = freetype.ParseFont(ttf)
 }
 
-// LoadFont let you load an external font
+// LoadFont let you load an external font.
 func LoadFont(fontData []byte) error {
 	var err error
 	ttfFont, err = freetype.ParseFont(fontData)
 	return err
 }
 
+// LoadFontFromReader load an external font from an io.Reader interface.
+func LoadFontFromReader(reader io.Reader) error {
+	var buf bytes.Buffer
+	if _, err := io.Copy(&buf, reader); err != nil {
+		return err
+	}
+
+	return LoadFont(buf.Bytes())
+}
+
 // New creates a new captcha.
 // It returns captcha data and any freetype drawing error encountered
 func New(width int, height int, option ...SetOption) (*Data, error) {

captcha_test.go

@@ -5,6 +5,7 @@ import (
 	"golang.org/x/image/font/gofont/goregular"
 	"image/color"
 	"math/rand"
+	"os"
 	"testing"
 )
 
@@ -73,6 +74,17 @@ func TestLoadFont(t *testing.T) {
 	}
 }
 
+func TestLoadFontFromReader(t *testing.T) {
+	file, err := os.Open("./fonts/Comismsh.ttf")
+	if err != nil {
+		t.Fatal("Fail to load test file")
+	}
+
+	if err = LoadFontFromReader(file); err != nil {
+		t.Fatal("Fail to load font from io.Reader")
+	}
+}
+
 func TestMaxColor(t *testing.T) {
 	var result uint32
 	result = maxColor()

history.md

@@ -1,13 +1,16 @@
 0.12.0 / 2017-10-07
 ===================
+
 * Add FontDPI and FontScale options
 
 0.11.0 / 2017-09-28
 ===================
+
 * Add NewMathExpr API
 
 0.10.0 / 2017-09-23
 ===================
+
 * Add LoadFont API
 
 0.9.0 / 2017-09-20