Add simplemap backend

backend/simplemap/simplemap.go

@@ -0,0 +1,44 @@
+package simplemap
+
+import (
+	"github.com/heetch/confita"
+	"github.com/pkg/errors"
+	"reflect"
+
+	"context"
+)
+
+// Backend that loads config from map
+type Backend struct {
+	theMap map[string]interface{}
+}
+
+// NewBackend creates a simplemap backend.
+func NewBackend(theMap map[string]interface{}) *Backend {
+	return &Backend{
+		theMap: theMap,
+	}
+}
+
+// LoadStruct takes a struct config and loads the map into it
+func (b *Backend) LoadStruct(ctx context.Context, cfg *confita.StructConfig) error {
+	for _, f := range cfg.Fields {
+		mapVal := b.theMap[f.Key]
+		if mapVal == nil {
+			continue
+		}
+		mapRef := reflect.ValueOf(mapVal)
+		f.Value.Set(mapRef)
+	}
+	return nil
+}
+
+// Get is not implemented.
+func (b *Backend) Get(ctx context.Context, key string) ([]byte, error) {
+	return nil, errors.New("not implemented")
+}
+
+// Name returns the name of the flags backend.
+func (b *Backend) Name() string {
+	return "simplemap"
+}

backend/simplemap/simplemap_test.go

@@ -0,0 +1,39 @@
+package simplemap_test
+
+import (
+	"context"
+	"github.com/heetch/confita"
+	"github.com/heetch/confita/backend/simplemap"
+	"github.com/stretchr/testify/require"
+	"testing"
+	"time"
+)
+
+func TestSimplemapBackend(t *testing.T) {
+	type config struct {
+		Name     string        `config:"Name"`
+		Age      int           `config:"Age"`
+		Negative int           `config:"Negative"`
+		Balance  float64       `config:"Balance"`
+		Timeout  time.Duration `config:"Timeout"`
+	}
+
+	b := simplemap.NewBackend(map[string]interface{}{
+		"Name":     "Bob",
+		"Age":      30,
+		"Negative": -10,
+		"Balance":  1234.56,
+		"Timeout":  10 * time.Second,
+	})
+
+	var c config
+	require.Equal(t, "simplemap", b.Name())
+	err := confita.NewLoader(b).Load(context.Background(), &c)
+
+	require.NoError(t, err)
+	require.Equal(t, "Bob", c.Name)
+	require.Equal(t, 30, c.Age)
+	require.Equal(t, -10, c.Negative)
+	require.Equal(t, 1234.56, c.Balance)
+	require.Equal(t, 10*time.Second, c.Timeout)
+}