Print a warning when using an experimental feature (#2361)

* Print a warning when using an experimental feature

Signed-off-by: Goutham Veeramachaneni <[email protected]>

* Address feedback

Signed-off-by: Goutham Veeramachaneni <[email protected]>

Author: gouthamve

pkg/chunk/azure/blob_storage_client.go

@@ -13,6 +13,7 @@ import (
 	"github.com/Azure/azure-storage-blob-go/azblob"
 
 	"github.com/cortexproject/cortex/pkg/chunk"
+	"github.com/cortexproject/cortex/pkg/util"
 	"github.com/cortexproject/cortex/pkg/util/flagext"
 )
 
@@ -63,6 +64,7 @@ type BlobStorage struct {
 
 // NewBlobStorage creates a new instance of the BlobStorage struct.
 func NewBlobStorage(cfg *BlobStorageConfig, delimiter string) (*BlobStorage, error) {
+	util.WarnExperimentalUse("Azure Blob Storage")
 	blobStorage := &BlobStorage{
 		cfg:       cfg,
 		delimiter: delimiter,

pkg/chunk/cache/fifo_cache.go

@@ -9,6 +9,8 @@ import (
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
+
+	"github.com/cortexproject/cortex/pkg/util"
 )
 
 var (
@@ -113,6 +115,8 @@ type cacheEntry struct {
 // NewFifoCache returns a new initialised FifoCache of size.
 // TODO(bwplotka): Fix metrics, get them out of globals, separate or allow prefixing.
 func NewFifoCache(name string, cfg FifoCacheConfig) *FifoCache {
+	util.WarnExperimentalUse("In-memory (FIFO) cache")
+
 	cache := &FifoCache{
 		size:     cfg.Size,
 		validity: cfg.Validity,

pkg/chunk/cache/memcached_client.go

@@ -108,6 +108,7 @@ func NewMemcachedClient(cfg MemcachedClientConfig, name string, r prometheus.Reg
 	}
 
 	if len(cfg.Addresses) > 0 {
+		util.WarnExperimentalUse("DNS-based memcached service discovery")
 		newClient.addresses = strings.Split(cfg.Addresses, ",")
 	}
 

pkg/chunk/cache/redis_cache.go

@@ -44,6 +44,7 @@ func (cfg *RedisConfig) RegisterFlagsWithPrefix(prefix, description string, f *f
 
 // NewRedisCache creates a new RedisCache
 func NewRedisCache(cfg RedisConfig, name string, pool *redis.Pool) *RedisCache {
+	util.WarnExperimentalUse("Redis cache")
 	// pool != nil only in unit tests
 	if pool == nil {
 		pool = &redis.Pool{

pkg/chunk/cassandra/storage_client.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/cortexproject/cortex/pkg/chunk"
 	"github.com/cortexproject/cortex/pkg/chunk/util"
+	pkgutil "github.com/cortexproject/cortex/pkg/util"
 	"github.com/cortexproject/cortex/pkg/util/flagext"
 )
 
@@ -185,6 +186,8 @@ type StorageClient struct {
 
 // NewStorageClient returns a new StorageClient.
 func NewStorageClient(cfg Config, schemaCfg chunk.SchemaConfig) (*StorageClient, error) {
+	pkgutil.WarnExperimentalUse("Cassandra Backend")
+
 	session, err := cfg.session()
 	if err != nil {
 		return nil, errors.WithStack(err)

pkg/chunk/purger/purger.go

@@ -75,6 +75,8 @@ type DataPurger struct {
 
 // NewDataPurger creates a new DataPurger
 func NewDataPurger(cfg Config, deleteStore *DeleteStore, chunkStore chunk.Store, storageClient chunk.ObjectClient) (*DataPurger, error) {
+	util.WarnExperimentalUse("Delete series API")
+
 	dataPurger := DataPurger{
 		cfg:                 cfg,
 		deleteStore:         deleteStore,

pkg/cortex/modules.go

@@ -440,6 +440,8 @@ func (t *Cortex) initRuler(cfg *Config) (serv services.Service, err error) {
 	}
 
 	if cfg.Ruler.EnableAPI {
+		util.WarnExperimentalUse("Ruler API")
+
 		subrouter := t.server.HTTP.PathPrefix(cfg.HTTPPrefix).Subrouter()
 		t.ruler.RegisterRoutes(subrouter, t.httpAuthMiddleware)
 		ruler.RegisterRulerServer(t.server.GRPC, t.ruler)

pkg/ingester/ingester_v2.go

@@ -79,6 +79,7 @@ type TSDBState struct {
 
 // NewV2 returns a new Ingester that uses prometheus block storage instead of chunk storage
 func NewV2(cfg Config, clientConfig client.Config, limits *validation.Overrides, registerer prometheus.Registerer) (*Ingester, error) {
+	util.WarnExperimentalUse("Blocks storage engine")
 	bucketClient, err := cortex_tsdb.NewBucketClient(context.Background(), cfg.TSDBConfig, "cortex", util.Logger)
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to create the bucket client")

pkg/ingester/wal.go

@@ -82,6 +82,8 @@ func newWAL(cfg WALConfig, userStatesFunc func() map[string]*userState, register
 		return &noopWAL{}, nil
 	}
 
+	util.WarnExperimentalUse("Chunks WAL")
+
 	var walRegistry prometheus.Registerer
 	if registerer != nil {
 		walRegistry = prometheus.WrapRegistererWith(prometheus.Labels{"kind": "wal"}, registerer)

pkg/querier/block.go

@@ -32,6 +32,7 @@ type BlockQueryable struct {
 
 // NewBlockQueryable returns a client to query a block store
 func NewBlockQueryable(cfg tsdb.Config, logLevel logging.Level, registerer prometheus.Registerer) (*BlockQueryable, error) {
+	util.WarnExperimentalUse("Blocks storage engine")
 	bucketClient, err := tsdb.NewBucketClient(context.Background(), cfg, "cortex-userstore", util.Logger)
 	if err != nil {
 		return nil, err