Document proto bytes field decoding with a test (#1509)

Author: Jorres

ydb/library/yaml_config/yaml_config_parser.cpp

@@ -943,10 +943,12 @@ namespace NKikimr::NYaml {
         return result;
     }
 
-    void Parse(const TString& data, NKikimrConfig::TAppConfig& config) {
+    void Parse(const TString& data, NKikimrConfig::TAppConfig& config, bool needsTransforming) {
         auto yamlNode = YAML::Load(data);
         NJson::TJsonValue jsonNode = Yaml2Json(yamlNode, true);
-        TransformConfig(jsonNode);
+        if (needsTransforming) {
+            TransformConfig(jsonNode);
+        }
         NProtobufJson::MergeJson2Proto(jsonNode, config, GetJsonToProtoConfig());
     }
 }

ydb/library/yaml_config/yaml_config_parser.h

@@ -19,5 +19,5 @@ namespace NKikimr::NYaml {
 
     void TransformConfig(NJson::TJsonValue& config, bool relaxed = false);
 
-    void Parse(const TString& data, NKikimrConfig::TAppConfig& config);
+    void Parse(const TString& data, NKikimrConfig::TAppConfig& config, bool needsTransforming = true);
 }

ydb/library/yaml_config/yaml_config_ut.cpp

@@ -1,4 +1,5 @@
 #include "yaml_config.h"
+#include "yaml_config_parser.h"
 
 #include <library/cpp/testing/unittest/registar.h>
 
@@ -1767,4 +1768,24 @@ obj: {value: 2} # comment2
             UNIT_ASSERT_VALUES_EQUAL(res, exp);
         }
     }
+
+    Y_UNIT_TEST(ProtoBytesFieldDoesNotDecodeBase64) {
+    // "c2FtcGxlLXBpbgo=" -> base64 decode -> "sample-pin"
+            TString config = R"(
+pdisk_key_config:
+  keys:
+  - container_path: "/a/b/c"
+    pin: "c2FtcGxlLXBpbgo="
+    id: "sample-encryption-key"
+    version: 1
+)";
+        NKikimrConfig::TAppConfig cfg;
+        NKikimr::NYaml::Parse(config, cfg, false);
+
+        UNIT_ASSERT(cfg.has_pdiskkeyconfig());
+        auto keys = cfg.pdiskkeyconfig().GetKeys();
+        UNIT_ASSERT_VALUES_EQUAL(keys.end() - keys.begin(), 1);
+        auto key = keys.at(0);
+        UNIT_ASSERT_VALUES_EQUAL("c2FtcGxlLXBpbgo=", key.pin());
+    }
 }