Add multistore for dashboards

multistore/dashboards.go

@@ -0,0 +1,97 @@
+package multistore
+
+import (
+	"context"
+
+	"github.com/influxdata/chronograf"
+)
+
+// Ensure DashboardsStore implements chronograf.DashboardsStore.
+var _ chronograf.DashboardsStore = &DashboardsStore{}
+
+// DashboardsStore implements the chronograf.DashboardsStore interface, and
+// delegates to all contained DashboardsStores
+type DashboardsStore struct {
+	Stores []chronograf.DashboardsStore
+}
+
+// All concatenates the Dashboards of all contained Stores
+func (multi *DashboardsStore) All(ctx context.Context) ([]chronograf.Dashboard, error) {
+	all := []chronograf.Dashboard{}
+	boardSet := map[chronograf.DashboardID]struct{}{}
+
+	ok := false
+	var err error
+	for _, store := range multi.Stores {
+		var boards []chronograf.Dashboard
+		boards, err = store.All(ctx)
+		if err != nil {
+			// If this Store is unable to return an array of dashboards, skip to the
+			// next Store.
+			continue
+		}
+		ok = true // We've received a response from at least one Store
+		for _, board := range boards {
+			// Enforce that the dashboard has a unique ID
+			// If the ID has been seen before, ignore the dashboard
+			if _, okay := boardSet[board.ID]; !okay { // We have a new dashboard
+				boardSet[board.ID] = struct{}{} // We just care that the ID is unique
+				all = append(all, board)
+			}
+		}
+	}
+	if !ok {
+		return nil, err
+	}
+	return all, nil
+}
+
+// Add the dashboard to the first responsive Store
+func (multi *DashboardsStore) Add(ctx context.Context, dashboard chronograf.Dashboard) (chronograf.Dashboard, error) {
+	var err error
+	for _, store := range multi.Stores {
+		var d chronograf.Dashboard
+		d, err = store.Add(ctx, dashboard)
+		if err == nil {
+			return d, nil
+		}
+	}
+	return chronograf.Dashboard{}, nil
+}
+
+// Delete delegates to all Stores, returns success if one Store is successful
+func (multi *DashboardsStore) Delete(ctx context.Context, dashboard chronograf.Dashboard) error {
+	var err error
+	for _, store := range multi.Stores {
+		err = store.Delete(ctx, dashboard)
+		if err == nil {
+			return nil
+		}
+	}
+	return err
+}
+
+// Get finds the Dashboard by id among all contained Stores
+func (multi *DashboardsStore) Get(ctx context.Context, id chronograf.DashboardID) (chronograf.Dashboard, error) {
+	var err error
+	for _, store := range multi.Stores {
+		var d chronograf.Dashboard
+		d, err = store.Get(ctx, id)
+		if err == nil {
+			return d, nil
+		}
+	}
+	return chronograf.Dashboard{}, nil
+}
+
+// Update the first responsive Store
+func (multi *DashboardsStore) Update(ctx context.Context, dashboard chronograf.Dashboard) error {
+	var err error
+	for _, store := range multi.Stores {
+		err = store.Update(ctx, dashboard)
+		if err == nil {
+			return nil
+		}
+	}
+	return err
+}