dynamo-query: added delete attribute command

internal/dynamo-browse/controllers/attrpath.go

@@ -31,6 +31,38 @@ func (ap attrPath) follow(item models.Item) (types.AttributeValue, error) {
 	return step, nil
 }
 
+func (ap attrPath) deleteAt(item models.Item) error {
+	if len(ap) == 1 {
+		delete(item, ap[0])
+		return nil
+	}
+
+	var step types.AttributeValue
+	for i, seg := range ap[:len(ap)-1] {
+		if i == 0 {
+			step = item[seg]
+			continue
+		}
+
+		switch s := step.(type) {
+		case *types.AttributeValueMemberM:
+			step = s.Value[seg]
+		default:
+			return errors.Errorf("seg %v expected to be a map", i)
+		}
+	}
+
+	lastSeg := ap[len(ap)-1]
+	switch s := step.(type) {
+	case *types.AttributeValueMemberM:
+		delete(s.Value, lastSeg)
+	default:
+		return errors.Errorf("last seg expected to be a map, but was %T", lastSeg)
+	}
+
+	return nil
+}
+
 func (ap attrPath) setAt(item models.Item, newValue types.AttributeValue) error {
 	if len(ap) == 1 {
 		item[ap[0]] = newValue

internal/dynamo-browse/controllers/tablewrite.go

@@ -138,6 +138,35 @@ func (twc *TableWriteController) SetNumberValue(idx int, key string) tea.Cmd {
 	}
 }
 
+func (twc *TableWriteController) DeleteAttribute(idx int, key string) tea.Cmd {
+	return func() tea.Msg {
+		// Verify that the expression is valid
+		apPath := newAttrPath(key)
+
+		if err := twc.state.withResultSetReturningError(func(set *models.ResultSet) error {
+			_, err := apPath.follow(set.Items()[idx])
+			return err
+		}); err != nil {
+			return events.Error(err)
+		}
+
+		if err := twc.state.withResultSetReturningError(func(set *models.ResultSet) error {
+			err := apPath.deleteAt(set.Items()[idx])
+			if err != nil {
+				return err
+			}
+
+			set.SetDirty(idx, true)
+			set.RefreshColumns()
+			return nil
+		}); err != nil {
+			return events.Error(err)
+		}
+
+		return ResultSetUpdated{}
+	}
+}
+
 func (twc *TableWriteController) PutItem(idx int) tea.Cmd {
 	return func() tea.Msg {
 		resultSet := twc.state.ResultSet()

internal/dynamo-browse/controllers/tablewrite_test.go

@@ -135,6 +135,51 @@ func TestTableWriteController_SetNumberValue(t *testing.T) {
 	})
 }
 
+func TestTableWriteController_DeleteAttribute(t *testing.T) {
+	client, cleanupFn := testdynamo.SetupTestTable(t, testData)
+	defer cleanupFn()
+
+	provider := dynamo.NewProvider(client)
+	service := tables.NewService(provider)
+
+	t.Run("should delete top level attribute", func(t *testing.T) {
+		state := controllers.NewState()
+		readController := controllers.NewTableReadController(state, service, "alpha-table")
+		writeController := controllers.NewTableWriteController(state, service, readController)
+
+		invokeCommand(t, readController.Init())
+		before, _ := state.ResultSet().Items()[0].AttributeValueAsString("age")
+		assert.Equal(t, "23", before)
+		assert.False(t, state.ResultSet().IsDirty(0))
+
+		invokeCommand(t, writeController.DeleteAttribute(0, "age"))
+
+		_, hasAge := state.ResultSet().Items()[0]["age"]
+		assert.False(t, hasAge)
+	})
+
+	t.Run("should delete attribute of map", func(t *testing.T) {
+		state := controllers.NewState()
+		readController := controllers.NewTableReadController(state, service, "alpha-table")
+		writeController := controllers.NewTableWriteController(state, service, readController)
+
+		invokeCommand(t, readController.Init())
+
+		beforeAddress := state.ResultSet().Items()[0]["address"].(*types.AttributeValueMemberM)
+		beforeStreet := beforeAddress.Value["no"].(*types.AttributeValueMemberN).Value
+
+		assert.Equal(t, "123", beforeStreet)
+		assert.False(t, state.ResultSet().IsDirty(0))
+
+		invokeCommand(t, writeController.DeleteAttribute(0, "address.no"))
+
+		afterAddress := state.ResultSet().Items()[0]["address"].(*types.AttributeValueMemberM)
+		_, hasStreet := afterAddress.Value["no"]
+
+		assert.False(t, hasStreet)
+	})
+}
+
 func TestTableWriteController_PutItem(t *testing.T) {
 	t.Run("should put the selected item if dirty", func(t *testing.T) {
 		client, cleanupFn := testdynamo.SetupTestTable(t, testData)

internal/dynamo-browse/ui/model.go

@@ -68,6 +68,12 @@ func NewModel(rc *controllers.TableReadController, wc *controllers.TableWriteCon
 				}
 				return wc.SetNumberValue(dtv.SelectedItemIndex(), args[0])
 			},
+			"del-attr": func(args []string) tea.Cmd {
+				if len(args) == 0 {
+					return events.SetError(errors.New("expected field"))
+				}
+				return wc.DeleteAttribute(dtv.SelectedItemIndex(), args[0])
+			},
 
 			"put": func(args []string) tea.Cmd {
 				return wc.PutItem(dtv.SelectedItemIndex())