Started the implementation of getMusicDirectory. Probably will need to introduce a new 'service' layer...

tests/mocks/mock_artist_repo.go

@@ -0,0 +1,38 @@
+package mocks
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/deluan/gosonic/domain"
+"errors"
+)
+
+func CreateMockArtistRepo() *MockArtist {
+	return &MockArtist{}
+}
+
+type MockArtist struct {
+	domain.ArtistRepository
+	data map[string]domain.Artist
+	err  bool
+}
+
+func (m *MockArtist) SetError(err bool) {
+	m.err = err
+}
+
+func (m *MockArtist) SetData(j string) {
+	m.data = make(map[string]domain.Artist)
+	err := json.Unmarshal([]byte(j), &m.data)
+	if err != nil {
+		fmt.Println("ERROR: ", err)
+	}
+}
+
+func (m *MockArtist) Exists(id string) (bool, error) {
+	if m.err {
+		return false, errors.New("Error!")
+	}
+	_, found := m.data[id];
+	return found, nil
+}