Improve startup speed

pkg/config/context.go

@@ -4,18 +4,37 @@
 package config
 
 import (
+	"crypto/sha256"
+	"encoding/hex"
+
 	"github.com/pkg/errors"
+	"gopkg.in/yaml.v2"
 
+	"github.com/vmware-tanzu/tanzu-cli/pkg/datastore"
 	"github.com/vmware-tanzu/tanzu-plugin-runtime/config"
+	"github.com/vmware-tanzu/tanzu-plugin-runtime/config/types"
 )
 
+type contextAndServerSha struct {
+	ContextsSha        string
+	CurrentContextsSha string
+	ServersSha         string
+	CurrentServerSha   string
+}
+
+const lastContextServerShasKey = "lastContextServerShas"
+
 // SyncContextsAndServers populate or sync contexts and servers
 func SyncContextsAndServers() error {
 	cfg, err := config.GetClientConfig()
 	if err != nil {
 		return errors.Wrap(err, "failed to get client config")
 	}
 
+	if !shouldSyncContextsAndServers(cfg) {
+		return nil
+	}
+
 	config.PopulateContexts(cfg)
 
 	// Now write the context to the configuration file.  This will also create any missing server for its corresponding context
@@ -34,5 +53,76 @@ func SyncContextsAndServers() error {
 			return errors.Wrap(err, "failed to set active context")
 		}
 	}
+
+	// After the sync, save the shas using the updated config
+	// so that next time, we avoid synching if the shas are the same
+	cfg, err = config.GetClientConfig()
+	if err == nil {
+		_ = saveContextAndServerShas(cfg)
+	}
 	return nil
 }
+
+func shouldSyncContextsAndServers(cfg *types.ClientConfig) bool {
+	var prevShas contextAndServerSha
+	err := datastore.GetDataStoreValue(lastContextServerShasKey, &prevShas)
+	if err != nil {
+		return true
+	}
+
+	newShas := computeShasForSync(cfg)
+	if newShas == nil || prevShas != *newShas {
+		return true
+	}
+	return false
+}
+
+//nolint:staticcheck // Deprecated
+func computeShasForSync(cfg *types.ClientConfig) *contextAndServerSha {
+	// tanzu contexts are not synced so we don't include them in the sha
+	// because even if they change, we don't need to sync them
+	var nonTanzuContexts []*types.Context
+	for i := range cfg.KnownContexts {
+		if cfg.KnownContexts[i].ContextType != types.ContextTypeTanzu {
+			nonTanzuContexts = append(nonTanzuContexts, cfg.KnownContexts[i])
+		}
+	}
+	ctxBytes, err := yaml.Marshal(nonTanzuContexts)
+	if err != nil {
+		return nil
+	}
+
+	// tanzu servers are not synced so we don't include them in the sha
+	// because even if they change, we don't need to sync them.
+	// Note that tanzu servers should normally not be in the known servers list
+	// but could happen for some older plugins or CLI versions which used to sync them.
+	var nonTanzuServers []*types.Server
+	for i := range cfg.KnownServers {
+		if cfg.KnownServers[i].Type != types.ServerType(types.ContextTypeTanzu) {
+			nonTanzuServers = append(nonTanzuServers, cfg.KnownServers[i])
+		}
+	}
+	serverBytes, err := yaml.Marshal(nonTanzuServers)
+	if err != nil {
+		return nil
+	}
+
+	return &contextAndServerSha{
+		ContextsSha: hashString(string(ctxBytes)),
+		// Only the k8s current context is synched
+		CurrentContextsSha: hashString(cfg.CurrentContext[types.ContextTypeK8s]),
+		ServersSha:         hashString(string(serverBytes)),
+		CurrentServerSha:   hashString(cfg.CurrentServer),
+	}
+}
+
+func saveContextAndServerShas(cfg *types.ClientConfig) error {
+	newShas := computeShasForSync(cfg)
+	return datastore.SetDataStoreValue(lastContextServerShasKey, newShas)
+}
+
+func hashString(str string) string {
+	h := sha256.New()
+	h.Write([]byte(str))
+	return hex.EncodeToString(h.Sum(nil))
+}

pkg/lastversion/last_version.go

@@ -47,10 +47,17 @@ func GetLastExecutedCLIVersion() string {
 
 // SetLastExecutedCLIVersion sets the last executed CLI version in the datastore.
 func SetLastExecutedCLIVersion() {
-	_ = datastore.SetDataStoreValue(lastExecutedCLIVersionKey, lastExecutedCLIVersion{Version: buildinfo.Version})
+	var prevLastVersion lastExecutedCLIVersion
+	_ = datastore.GetDataStoreValue(lastExecutedCLIVersionKey, &prevLastVersion)
+	if prevLastVersion.Version != buildinfo.Version {
+		// Only update the last executed version if it is different from the one already stored.
+		_ = datastore.SetDataStoreValue(lastExecutedCLIVersionKey, lastExecutedCLIVersion{Version: buildinfo.Version})
+	}
 
 	// Just in case the 'features.global.context-target-v2' feature flag is still set
 	// because the last version executed was < 1.3.0, we must remove it.
 	parts := strings.Split(constants.FeatureContextCommand, ".")
-	_ = config.DeleteFeature(parts[1], parts[2])
+	if enabled, err := config.IsFeatureEnabled(parts[1], parts[2]); err == nil && enabled {
+		_ = config.DeleteFeature(parts[1], parts[2])
+	}
 }