fix(libs): fixed issues with expert sharing returning errors when meta.json is absent.

Author: FZR95

CHANGELOG.md

@@ -5,6 +5,26 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+## [0.3.0] - 2026-03-01
+
+### Added
+
+- **Expert share to platform**: `POST /topics/{id}/experts/{name}/share` — share topic-level expert to `libs/experts/topiclab_shared/`; rejects built-in experts (source=default); reloads EXPERT_SPECS and invalidates libs cache
+- **Moderator mode share to platform**: `POST /topics/{id}/moderator-mode/share` — share custom moderator mode to `libs/moderator_modes/topiclab_shared/`; body: `mode_id`, `name?`, `description?`; creates meta.json if missing
+- **Topic-level moderator config**: `GET/PUT /topics/{id}/moderator-mode` supports `skill_list`, `mcp_server_ids`, `model`; persisted per topic; fallback from `config/skills/` and `config/mcp.json` when missing
+- **Discussion params**: `POST /topics/{id}/discussion` accepts `skill_list`, `mcp_server_ids`, `allowed_tools`; copied to topic workspace for moderator/agent use
+
+### Fixed
+
+- **Expert share 500**: `POST /topics/{id}/experts/{name}/share` no longer returns 500 when `libs/experts/topiclab_shared/meta.json` does not exist (first share). Creates default meta structure like moderator-mode share.
+
+### Changed
+
+- Topic moderator mode config: skill_list, mcp_server_ids, model persisted in workspace; discussion uses topic config when present
+- Expert share: creates `topiclab_shared/meta.json` with default categories when missing (aligned with moderator-mode share)
+
 ## [0.2.0] - 2026-02-21
 
 ### Added

app/api/topic_experts.py

@@ -250,9 +250,22 @@ def share_expert_to_platform(topic_id: str, expert_name: str):
     skill_file_name = f"{expert_name}.md"
     (shared_dir / skill_file_name).write_text(role_file.read_text(encoding="utf-8"), encoding="utf-8")
 
-    # Update topiclab_shared/meta.json
+    # Update topiclab_shared/meta.json (create if missing, like moderator_mode share)
     meta_path = shared_dir / "meta.json"
-    meta = json.loads(meta_path.read_text(encoding="utf-8"))
+    if meta_path.exists():
+        meta = json.loads(meta_path.read_text(encoding="utf-8"))
+    else:
+        meta = {
+            "common_sections": "expert_common.md",
+            "categories": {
+                "topiclab": {
+                    "id": "topiclab",
+                    "name": "TopicLab",
+                    "description": "User-shared experts from frontend",
+                }
+            },
+            "experts": {},
+        }
     meta.setdefault("experts", {})[expert_name] = {
         "id": expert_name,
         "source": "topiclab_shared",

libs/experts/topiclab_shared/meta.json

@@ -7,5 +7,16 @@
       "description": "User-shared experts from frontend"
     }
   },
-  "experts": {}
-}
+  "experts": {
+    "test_shared_expert": {
+      "id": "test_shared_expert",
+      "source": "topiclab_shared",
+      "name": "test_shared_expert",
+      "label": "Test Shared",
+      "description": "For share test",
+      "category": "topiclab",
+      "skill_file": "test_shared_expert.md",
+      "perspective": "test_shared_expert"
+    }
+  }
+}

tests/test_api.py

@@ -458,14 +458,42 @@ def test_moderator_mode_get_and_set(client: TestClient, isolated_workspace: Path
     assert reloaded["model"] == "qwen-flash"
 
 
+def test_expert_share_when_meta_json_missing(client: TestClient, isolated_workspace: Path, monkeypatch):
+    """Share succeeds when topiclab_shared/meta.json does not exist (first share)."""
+    from app.core.config import get_experts_dir
+
+    # Use isolated experts dir with no topiclab_shared/meta.json
+    experts_root = isolated_workspace / "libs" / "experts"
+    experts_root.mkdir(parents=True)
+    monkeypatch.setattr("app.api.topic_experts.get_experts_dir", lambda: experts_root)
+
+    topic = _create_topic(client)
+    topic_id = topic["id"]
+    ws_path = isolated_workspace / "topics" / topic_id
+    (ws_path / "agents" / "first_share_expert").mkdir(parents=True)
+    (ws_path / "agents" / "first_share_expert" / "role.md").write_text("# First Share", encoding="utf-8")
+    (ws_path / "config").mkdir(parents=True, exist_ok=True)
+    meta = {"experts": [{"name": "first_share_expert", "label": "First", "description": "First share test"}]}
+    (ws_path / "config" / "experts_metadata.json").write_text(json.dumps(meta, ensure_ascii=False), encoding="utf-8")
+
+    resp = client.post(f"/topics/{topic_id}/experts/first_share_expert/share")
+    assert resp.status_code == 200
+    assert resp.json().get("expert_name") == "first_share_expert"
+
+    meta_path = experts_root / "topiclab_shared" / "meta.json"
+    assert meta_path.exists()
+    meta_data = json.loads(meta_path.read_text(encoding="utf-8"))
+    assert "first_share_expert" in meta_data.get("experts", {})
+
+
 def test_expert_share_to_topiclab_shared(client: TestClient, isolated_workspace: Path):
     """POST /topics/{id}/experts/{name}/share writes to topiclab_shared and reloads."""
     from app.core.config import get_experts_dir
 
     topic = _create_topic(client)
     topic_id = topic["id"]
     ws_path = isolated_workspace / "topics" / topic_id
-    (ws_path / "agents" / "test_shared_expert").mkdir(parents=True)
+    (ws_path / "agents" / "test_shared_expert").mkdir(parents=True, exist_ok=True)
     (ws_path / "agents" / "test_shared_expert" / "role.md").write_text("# Test Expert\nRole content.", encoding="utf-8")
     (ws_path / "config").mkdir(parents=True, exist_ok=True)
     meta = {"experts": [{"name": "test_shared_expert", "label": "Test Shared", "description": "For share test"}]}
@@ -493,7 +521,7 @@ def test_expert_share_rejects_builtin(client: TestClient, isolated_workspace: Pa
     topic = _create_topic(client)
     topic_id = topic["id"]
     ws_path = isolated_workspace / "topics" / topic_id
-    (ws_path / "agents" / "physicist").mkdir(parents=True)
+    (ws_path / "agents" / "physicist").mkdir(parents=True, exist_ok=True)
     (ws_path / "agents" / "physicist" / "role.md").write_text("# Custom Physicist", encoding="utf-8")
     (ws_path / "config").mkdir(parents=True, exist_ok=True)
     meta = {"experts": [{"name": "physicist", "label": "Custom", "description": "Test"}]}