Change to only store a prefix of the datastore's unique ID in the zed…

…token

Results in smaller tokens but given that datastore IDs are generated, should still minimize the chances of a conflict

pkg/zedtoken/zedtoken.go

@@ -46,6 +46,8 @@ const (
 	StatusMismatchedDatastoreID
 )
 
+const uniqueIDPrefixLength = 8
+
 // MustNewFromRevisionForTesting generates an encoded zedtoken from an integral revision.
 func MustNewFromRevisionForTesting(revision datastore.Revision) *v1.ZedToken {
 	encoded, err := newFromRevision(revision, legacyEmptyDatastoreID)
@@ -66,11 +68,16 @@ func NewFromRevision(ctx context.Context, revision datastore.Revision, ds datast
 }
 
 func newFromRevision(revision datastore.Revision, datastoreUniqueID string) (*v1.ZedToken, error) {
+	datastoreUniqueIDPrefix := datastoreUniqueID
+	if len(datastoreUniqueIDPrefix) > uniqueIDPrefixLength {
+		datastoreUniqueIDPrefix = datastoreUniqueIDPrefix[0:uniqueIDPrefixLength]
+	}
+
 	toEncode := &zedtoken.DecodedZedToken{
 		VersionOneof: &zedtoken.DecodedZedToken_V1{
 			V1: &zedtoken.DecodedZedToken_V1ZedToken{
-				Revision:          revision.String(),
-				DatastoreUniqueId: datastoreUniqueID,
+				Revision:                revision.String(),
+				DatastoreUniqueIdPrefix: datastoreUniqueIDPrefix,
 			},
 		},
 	}
@@ -132,7 +139,7 @@ func DecodeRevision(encoded *v1.ZedToken, ds revisionDecoder) (datastore.Revisio
 			return datastore.NoRevision, StatusUnknown, fmt.Errorf(errDecodeError, err)
 		}
 
-		if ver.V1.DatastoreUniqueId == legacyEmptyDatastoreID {
+		if ver.V1.DatastoreUniqueIdPrefix == legacyEmptyDatastoreID {
 			return parsed, StatusLegacyEmptyDatastoreID, nil
 		}
 
@@ -141,7 +148,12 @@ func DecodeRevision(encoded *v1.ZedToken, ds revisionDecoder) (datastore.Revisio
 			return datastore.NoRevision, StatusUnknown, fmt.Errorf(errDecodeError, err)
 		}
 
-		if ver.V1.DatastoreUniqueId != datastoreUniqueID {
+		datastoreUniqueIDPrefix := datastoreUniqueID
+		if len(datastoreUniqueIDPrefix) > uniqueIDPrefixLength {
+			datastoreUniqueIDPrefix = datastoreUniqueIDPrefix[0:uniqueIDPrefixLength]
+		}
+
+		if ver.V1.DatastoreUniqueIdPrefix != datastoreUniqueIDPrefix {
 			return parsed, StatusMismatchedDatastoreID, nil
 		}
 

pkg/zedtoken/zedtoken_test.go

@@ -141,15 +141,15 @@ var decodeTests = []struct {
 	},
 	{
 		format:            "V1 ZedToken with matching datastore unique ID",
-		token:             "GhIKAjQyEgxzb21ldW5pcXVlaWQ=",
+		token:             "Gg4KAjQyEghzb21ldW5pcQ==",
 		datastoreUniqueID: "someuniqueid",
 		expectedRevision:  revisions.NewForTransactionID(42),
 		expectedStatus:    StatusValid,
 		expectError:       false,
 	},
 	{
 		format:            "V1 ZedToken with mismatched datastore unique ID",
-		token:             "GhIKAjQyEgxzb21ldW5pcXVlaWQ=",
+		token:             "Gg4KAjQyEghzb21ldW5pcQ==",
 		datastoreUniqueID: "anotheruniqueid",
 		expectedRevision:  revisions.NewForTransactionID(42),
 		expectedStatus:    StatusMismatchedDatastoreID,
@@ -225,7 +225,7 @@ var hlcDecodeTests = []struct {
 	},
 	{
 		format:            "V1 ZedToken with matching datastore unique ID",
-		token:             "GkYKHjE2OTM1NDA5NDAzNzMwNDU3MjcuMDAwMDAwMDAwMRIkNjM0OWFhZjItMzdjZC00N2I5LTg0ZTgtZmU1ZmE2ZTJkZWFk",
+		token:             "GioKHjE2OTM1NDA5NDAzNzMwNDU3MjcuMDAwMDAwMDAwMRIINjM0OWFhZjI=",
 		datastoreUniqueID: "6349aaf2-37cd-47b9-84e8-fe5fa6e2dead",
 		expectedStatus:    StatusValid,
 		expectedRevision: (func() datastore.Revision {
@@ -243,7 +243,7 @@ var hlcDecodeTests = []struct {
 	},
 	{
 		format:            "V1 ZedToken with mismatched datastore unique ID",
-		token:             "GkYKHjE2OTM1NDA5NDAzNzMwNDU3MjcuMDAwMDAwMDAwMRIkNjM0OWFhZjItMzdjZC00N2I5LTg0ZTgtZmU1ZmE2ZTJkZWFk",
+		token:             "GioKHjE2OTM1NDA5NDAzNzMwNDU3MjcuMDAwMDAwMDAwMRIINjM0OWFhZjI=",
 		datastoreUniqueID: "arrrg-6349aaf2-37cd-47b9-84e8-fe5fa6e2dead",
 		expectedStatus:    StatusMismatchedDatastoreID,
 		expectedRevision: (func() datastore.Revision {

proto/internal/impl/v1/impl.proto

@@ -34,9 +34,9 @@ message DecodedZedToken {
   message V1ZedToken {
     string revision = 1;
 
-    // datastore_unique_id is the unique ID for the datastore. Will be empty for legacy
-    // tokens.
-    string datastore_unique_id = 2;
+    // datastore_unique_id_prefix is a prefix of the unique ID for the datastore that created
+    // this token. Will be empty for legacy tokens.
+    string datastore_unique_id_prefix = 2;
   }
   oneof version_oneof {
     V1Zookie deprecated_v1_zookie = 2;