[#207] Fix shards for disabled write_cache

Signed-off-by: a.berezin <a.berezin@yadro.com>

src/frostfs_testlib/storage/dataclasses/shard.py

@@ -56,9 +56,7 @@ class Shard:
         var_prefix = f"{SHARD_PREFIX}{shard_id}"
 
         blobstor_count = Shard._get_blobstor_count_from_section(config_object, shard_id)
-        blobstors = [
-            Blobstor.from_config_object(config_object, shard_id, blobstor_id) for blobstor_id in range(blobstor_count)
-        ]
+        blobstors = [Blobstor.from_config_object(config_object, shard_id, blobstor_id) for blobstor_id in range(blobstor_count)]
 
         write_cache_enabled = config_object.as_bool(f"{var_prefix}_WRITECACHE_ENABLED")
 
@@ -71,7 +69,13 @@ class Shard:
     @staticmethod
     def from_object(shard):
         metabase = shard["metabase"]["path"] if "path" in shard["metabase"] else shard["metabase"]
+        writecache_enabled = True
+        if "enabled" in shard["writecache"]:
+            writecache_enabled = shard["writecache"]["enabled"]
+
         writecache = shard["writecache"]["path"] if "path" in shard["writecache"] else shard["writecache"]
+        if not writecache_enabled:
+            writecache = ""
 
         # Currently due to issue we need to check if pilorama exists in keys
         # TODO: make pilorama mandatory after fix