[rekognition] Add helper for invalid image encoding

rekognition/error.go

@@ -0,0 +1,14 @@
+package rekognition
+
+import "strings"
+
+var msgInvalidImageEncoding = `InvalidImageFormatException: Invalid image encoding`
+
+// IsErrorInvalidImageEncoding checks if gicen error is `Invalid image encoding`.
+func IsErrorInvalidImageEncoding(err error) (ok bool) {
+	if err == nil {
+		return false
+	}
+
+	return strings.Contains(err.Error(), msgInvalidImageEncoding)
+}

rekognition/error_test.go

@@ -0,0 +1,35 @@
+package rekognition
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsErrorInvalidImageEncoding(t *testing.T) {
+	a := assert.New(t)
+
+	tests := []struct {
+		expected bool
+		text     string
+	}{
+		{true, "InvalidImageFormatException: Invalid image encoding"},
+		{true, "status code: 400, request id: 00ff00ff-00ff-00ff-00ff-00ff00ff00ff, InvalidImageFormatException: Invalid image encoding"},
+		{true, "InvalidImageFormatException: Invalid image encoding, error"},
+		{true, "error, InvalidImageFormatException: Invalid image encoding, error"},
+		{false, "No errors"},
+		{false, "InvalidImageFormatException: Invalid image encodin"},
+		{false, "nvalidImageFormatException: Invalid image encoding"},
+		{false, ""},
+	}
+
+	for _, tt := range tests {
+		target := fmt.Sprintf("%+v", tt)
+
+		err := errors.New(tt.text)
+		a.Equal(tt.expected, IsErrorInvalidImageEncoding(err), target)
+	}
+	a.Equal(false, IsErrorInvalidImageEncoding(nil), "When error=nil")
+}