Snapshot (#49)

Author: linglingye001

azureappconfiguration/azureappconfiguration.go

@@ -480,6 +480,11 @@ func (azappcfg *AzureAppConfiguration) loadFeatureFlags(ctx context.Context, set
 
 	dedupFeatureFlags := make(map[string]any, len(settingsResponse.settings))
 	for _, setting := range settingsResponse.settings {
+		// Skip non-feature flag settings
+		if setting.ContentType == nil || *setting.ContentType != featureFlagContentType {
+			continue
+		}
+
 		if setting.Key != nil {
 			var v map[string]any
 			if err := json.Unmarshal([]byte(*setting.Value), &v); err != nil {
@@ -725,7 +730,9 @@ func deduplicateSelectors(selectors []Selector) []Selector {
 
 func getFeatureFlagSelectors(selectors []Selector) []Selector {
 	for i := range selectors {
-		selectors[i].KeyFilter = featureFlagKeyPrefix + selectors[i].KeyFilter
+		if selectors[i].SnapshotName == "" {
+			selectors[i].KeyFilter = featureFlagKeyPrefix + selectors[i].KeyFilter
+		}
 	}
 
 	return selectors

azureappconfiguration/options.go

@@ -70,6 +70,12 @@ type Selector struct {
 	// Empty string or omitted value will use the default no-label filter.
 	// Note: Wildcards are not supported in label filters.
 	LabelFilter string
+
+	// Snapshot is a set of key-values selected from the App Configuration store based on the composition type and filters.
+	// Once created, it is stored as an immutable entity that can be referenced by name.
+	// SnapshotName specifies the name of the snapshot to retrieve.
+	// If SnapshotName is used in a selector, no key and label filter should be used for it. Otherwise, an error will be returned.
+	SnapshotName string
 }
 
 // KeyValueRefreshOptions contains optional parameters to configure the behavior of key-value settings refresh

azureappconfiguration/settings_client.go

@@ -6,6 +6,7 @@ package azureappconfiguration
 import (
 	"context"
 	"errors"
+	"fmt"
 	"log"
 
 	"github.com/Azure/AppConfiguration-GoProvider/azureappconfiguration/internal/tracing"
@@ -62,25 +63,46 @@ func (s *selectorSettingsClient) getSettings(ctx context.Context) (*settingsResp
 	settings := make([]azappconfig.Setting, 0)
 	pageETags := make(map[Selector][]*azcore.ETag)
 	for _, filter := range s.selectors {
-		selector := azappconfig.SettingSelector{
-			KeyFilter:   to.Ptr(filter.KeyFilter),
-			LabelFilter: to.Ptr(filter.LabelFilter),
-			Fields:      azappconfig.AllSettingFields(),
-		}
+		if filter.SnapshotName == "" {
+			selector := azappconfig.SettingSelector{
+				KeyFilter:   to.Ptr(filter.KeyFilter),
+				LabelFilter: to.Ptr(filter.LabelFilter),
+				Fields:      azappconfig.AllSettingFields(),
+			}
 
-		pager := s.client.NewListSettingsPager(selector, nil)
-		eTags := make([]*azcore.ETag, 0)
-		for pager.More() {
-			page, err := pager.NextPage(ctx)
+			pager := s.client.NewListSettingsPager(selector, nil)
+			eTags := make([]*azcore.ETag, 0)
+			for pager.More() {
+				page, err := pager.NextPage(ctx)
+				if err != nil {
+					return nil, err
+				} else if page.Settings != nil {
+					settings = append(settings, page.Settings...)
+					eTags = append(eTags, page.ETag)
+				}
+			}
+
+			pageETags[filter] = eTags
+		} else {
+			snapshot, err := s.client.GetSnapshot(ctx, filter.SnapshotName, nil)
 			if err != nil {
 				return nil, err
-			} else if page.Settings != nil {
-				settings = append(settings, page.Settings...)
-				eTags = append(eTags, page.ETag)
 			}
-		}
 
-		pageETags[filter] = eTags
+			if snapshot.CompositionType == nil || *snapshot.CompositionType != azappconfig.CompositionTypeKey {
+				return nil, fmt.Errorf("composition type for the selected snapshot '%s' must be 'key'", filter.SnapshotName)
+			}
+
+			pager := s.client.NewListSettingsForSnapshotPager(filter.SnapshotName, nil)
+			for pager.More() {
+				page, err := pager.NextPage(ctx)
+				if err != nil {
+					return nil, err
+				} else if page.Settings != nil {
+					settings = append(settings, page.Settings...)
+				}
+			}
+		}
 	}
 
 	return &settingsResponse{