fix(mcp): 修复配置导入、凭据管理与协议边界

修复生命周期锁阻塞事件循环、旧连接回调误停新连接及超时契约不一致。

补齐 MCP JSON 兼容导入、密钥拆分与失败重试，修复 Header 大小写草稿丢失，迁移大小写敏感的环境变量凭据。

在 SSE 行拼接前限制缓冲大小，增加并发、迁移和流式输入回归测试；忽略本机 MCP 数据及 server.json/servers.json。

验证：后端 185 项、前端 54 项测试通过，前端生产构建、相关文件 Ruff 与暂存差异检查通过。

backend/tests/test_api.py

@@ -2,6 +2,8 @@ import asyncio
 import threading
 from types import SimpleNamespace
 
+import pytest
+
 from app.contracts import (
     McpServerSecretStatus,
     McpServerSecretWriteRequest,
@@ -61,9 +63,7 @@ def test_mcp_secret_routes_offload_blocking_lifecycle_work(monkeypatch) -> None:
         )
     )
     deleted = asyncio.run(
-        routes.delete_mcp_server_secret(
-            "server-1", "TOKEN", kind="environment"
-        )
+        routes.delete_mcp_server_secret("server-1", "TOKEN", kind="environment")
     )
 
     assert written.configured is True
@@ -77,6 +77,172 @@ def test_health() -> None:
     assert response.model_dump() == {"status": "ok"}
 
 
+def test_mcp_create_and_trust_are_not_executed_on_event_loop(monkeypatch) -> None:
+    from app import routes
+    from app.contracts import McpServerCreateRequest, McpServerTrustRequest
+
+    caller = threading.get_ident()
+    workers = []
+
+    class Registry:
+        def create(self, request):
+            workers.append(threading.get_ident())
+            return "created"
+
+        def trust(self, server_id, digest):
+            workers.append(threading.get_ident())
+            return "trusted"
+
+    monkeypatch.setattr(routes, "container", SimpleNamespace(mcp_servers=Registry()))
+    assert (
+        asyncio.run(
+            routes.create_mcp_server(McpServerCreateRequest(name="test", command="uvx"))
+        )
+        == "created"
+    )
+    assert (
+        asyncio.run(
+            routes.trust_mcp_server(
+                "test", McpServerTrustRequest(command_digest="a" * 64)
+            )
+        )
+        == "trusted"
+    )
+    assert len(workers) == 2
+    assert all(worker != caller for worker in workers)
+
+
+def test_mcp_split_config_and_secret_requests_persist_without_plaintext(
+    monkeypatch,
+) -> None:
+    from fastapi.testclient import TestClient
+
+    from app import routes
+    from app.agent.tools import ToolRegistry
+    from app.config import get_settings
+    from app.extensions.mcp_registry import McpServerRegistry
+    from app.main import app
+    from app.providers.credentials import EncryptedCredentialStore
+
+    service = McpServerRegistry(
+        ToolRegistry(),
+        EncryptedCredentialStore(),
+        get_settings().data_dir,
+        allow_process_launch=True,
+    )
+    monkeypatch.setattr(routes, "container", SimpleNamespace(mcp_servers=service))
+    client = TestClient(app)
+    config = {
+        "name": "MiniMax configuration test",
+        "command": "uvx",
+        "environment": {"MINIMAX_API_HOST": "https://api.minimaxi.com"},
+        "secret_environment_keys": ["MINIMAX_API_KEY"],
+        "startup_timeout_seconds": 120,
+        "tool_timeout_seconds": 300,
+    }
+    # Reproduce the old frontend payload. The backend still enforces separation.
+    invalid = client.post(
+        "/api/mcp/servers",
+        json={
+            **config,
+            "environment": {
+                **config["environment"],
+                "MINIMAX_API_KEY": "synthetic-only",
+            },
+        },
+    )
+    assert invalid.status_code == 422
+    assert invalid.json()["error"]["code"] == "MCP_ENVIRONMENT_INVALID"
+    created = client.post("/api/mcp/servers", json=config)
+    assert created.status_code == 201
+    server_id = created.json()["server_id"]
+    saved = client.put(
+        f"/api/mcp/servers/{server_id}/secrets/MINIMAX_API_KEY",
+        json={"secret": "synthetic-only"},
+    )
+    assert saved.status_code == 200
+    current = client.get(f"/api/mcp/servers/{server_id}")
+    assert current.json()["secret_environment"] == {"MINIMAX_API_KEY": True}
+    assert "synthetic-only" not in current.text
+    assert "synthetic-only" not in service._path.read_text(encoding="utf-8")
+    _, credentials_path = service.credentials._paths()
+    assert "synthetic-only" not in credentials_path.read_text(encoding="utf-8")
+    assert not current.json()["enabled"]  # Saving never starts a third-party process.
+    client.close()
+
+
+@pytest.mark.parametrize("operation", ["create", "trust"])
+def test_mcp_lifecycle_lock_contention_keeps_event_loop_responsive(
+    monkeypatch,
+    operation,
+) -> None:
+    from app import routes
+    from app.agent.tools import ToolRegistry
+    from app.config import get_settings
+    from app.contracts import McpServerCreateRequest, McpServerTrustRequest
+    from app.extensions.mcp_registry import McpServerRegistry
+    from app.providers.credentials import EncryptedCredentialStore
+
+    service = McpServerRegistry(
+        ToolRegistry(),
+        EncryptedCredentialStore(),
+        get_settings().data_dir,
+        allow_process_launch=True,
+    )
+    request = McpServerCreateRequest(
+        name="Lock contention fixture", command="not-executed"
+    )
+    server = service.create(request)
+    monkeypatch.setattr(routes, "container", SimpleNamespace(mcp_servers=service))
+    entered = threading.Event()
+    locked = threading.Event()
+    release = threading.Event()
+    original = getattr(service, operation)
+
+    def observed(*args):
+        entered.set()
+        return original(*args)
+
+    def hold_lifecycle_lock():
+        with service._lifecycle_lock:
+            locked.set()
+            release.wait(timeout=5)
+
+    monkeypatch.setattr(service, operation, observed)
+    holder = threading.Thread(target=hold_lifecycle_lock, daemon=True)
+    holder.start()
+    # An independent watchdog lets the test fail rather than hang if a regression
+    # blocks the event loop itself (an asyncio timeout alone cannot catch that).
+    watchdog = threading.Timer(5, release.set)
+    watchdog.start()
+
+    async def exercise():
+        pending = asyncio.create_task(
+            routes.create_mcp_server(request)
+            if operation == "create"
+            else routes.trust_mcp_server(
+                server.server_id,
+                McpServerTrustRequest(command_digest=server.command_digest),
+            )
+        )
+        try:
+            assert await asyncio.to_thread(entered.wait, 2)
+            assert not pending.done()
+            assert not release.is_set()
+            assert (await health()).status == "ok"
+        finally:
+            release.set()
+            await pending
+
+    try:
+        assert locked.wait(timeout=2)
+        asyncio.run(exercise())
+    finally:
+        release.set()
+        watchdog.cancel()
+        holder.join(timeout=2)
+
+
 def test_service_status() -> None:
     response = asyncio.run(service_status())
 
@@ -93,7 +259,9 @@ def test_core_collections_are_typed() -> None:
 
     assert notes.items == []
     assert notes.page.limit == 20
-    assert [skill.manifest.skill_id for skill in skills.items] == ["knowledge-assistant"]
+    assert [skill.manifest.skill_id for skill in skills.items] == [
+        "knowledge-assistant"
+    ]
     assert skills.items[0].status == "ready"
     assert [plugin.manifest.plugin_id for plugin in plugins.items] == ["text-tools"]
     assert plugins.items[0].status == "ready"
@@ -114,9 +282,15 @@ def test_provider_presets_include_openai_and_deepseek() -> None:
 def test_provider_presets_static_route_precedes_provider_id_route() -> None:
     from app.routes import router
 
-    get_paths = [route.path for route in router.routes if "GET" in getattr(route, "methods", set())]
+    get_paths = [
+        route.path
+        for route in router.routes
+        if "GET" in getattr(route, "methods", set())
+    ]
 
-    assert get_paths.index("/api/providers/presets") < get_paths.index("/api/providers/{provider_id}")
+    assert get_paths.index("/api/providers/presets") < get_paths.index(
+        "/api/providers/{provider_id}"
+    )
 
 
 def test_openapi_contains_documented_frontend_interfaces() -> None:

backend/tests/test_mcp_registry.py

@@ -1,4 +1,5 @@
 import asyncio
+import hashlib
 import json
 import sys
 import threading
@@ -111,7 +112,9 @@ def test_update_disables_server_and_revokes_command_trust() -> None:
     service.shutdown()
 
 
-def test_update_remains_retryable_when_removed_secret_cleanup_fails(monkeypatch) -> None:
+def test_update_remains_retryable_when_removed_secret_cleanup_fails(
+    monkeypatch,
+) -> None:
     service = registry()
     created = service.create(request())
     service.put_secret(created.server_id, "TEST_MCP_SECRET", "keep-until-retry")
@@ -166,7 +169,9 @@ def test_unavailable_server_removes_bridge_host(monkeypatch) -> None:
     removed: list[str] = []
     monkeypatch.setattr(service.bridge, "remove", removed.append)
 
-    service._unavailable(created.server_id, "connection lost")
+    generation = object()
+    service._generations[created.server_id] = generation
+    service._unavailable(created.server_id, generation, "connection lost")
 
     current = service.get(created.server_id)
     assert removed == [f"mcp.{created.server_id}"]
@@ -175,6 +180,180 @@ def test_unavailable_server_removes_bridge_host(monkeypatch) -> None:
     service.shutdown()
 
 
+def test_old_failure_callback_cannot_stop_replacement_host(monkeypatch) -> None:
+    service = registry()
+    callbacks = []
+    original_start = service.bridge.start
+
+    def capture_callback(*args, **kwargs):
+        callbacks.append(args[4])
+        return original_start(*args, **kwargs)
+
+    monkeypatch.setattr(service.bridge, "start", capture_callback)
+    created = service.create(request(secret_environment_keys=[]))
+    service.trust(created.server_id, created.command_digest)
+    callback_thread = None
+    try:
+        service.test(created.server_id)
+        service.enable(created.server_id)
+        old_callback = callbacks[-1]
+        callback_started = threading.Event()
+        callback_finished = threading.Event()
+
+        def delayed_failure():
+            callback_started.set()
+            old_callback(f"mcp.{created.server_id}", "delayed old failure")
+            callback_finished.set()
+
+        # Queue the old callback while a replacement owns the lifecycle lock.
+        with service._lifecycle_lock:
+            callback_thread = threading.Thread(target=delayed_failure, daemon=True)
+            callback_thread.start()
+            assert callback_started.wait(timeout=2)
+            service.disable(created.server_id)
+            service.enable(created.server_id)
+        assert callback_finished.wait(timeout=2)
+        assert service.get(created.server_id).enabled is True
+        assert service.get(created.server_id).status == "ready"
+        assert service.tools.definitions()
+        callbacks[-1](f"mcp.{created.server_id}", "current failure")
+        assert service.get(created.server_id).enabled is False
+        assert service.get(created.server_id).status == "unhealthy"
+    finally:
+        service.shutdown()
+        if callback_thread is not None:
+            callback_thread.join(timeout=2)
+
+
+def test_header_case_only_rename_preserves_secret() -> None:
+    service = registry()
+    config = {
+        "name": "HTTP",
+        "transport": "streamable_http",
+        "url": "https://example.test/mcp",
+        "secret_header_keys": ["Authorization"],
+    }
+    created = service.create(McpServerCreateRequest(**config))
+    service.put_secret(created.server_id, "Authorization", "synthetic", kind="header")
+    config["secret_header_keys"] = ["authorization"]
+    updated = service.update(
+        created.server_id, McpServerUpdateRequest(**config, version=created.version)
+    )
+    assert updated.secret_headers == {"authorization": True}
+    assert (
+        service.credentials.resolve(
+            service._secret_id(created.server_id, "authorization", "header")
+        )
+        == "synthetic"
+    )
+
+
+def test_environment_secrets_are_case_sensitive_and_delete_independently() -> None:
+    service = registry()
+    created = service.create(request(secret_environment_keys=["TOKEN", "token"]))
+    service.put_secret(created.server_id, "TOKEN", "upper")
+    service.put_secret(created.server_id, "token", "lower")
+    assert (
+        service.credentials.resolve(service._secret_id(created.server_id, "TOKEN"))
+        == "upper"
+    )
+    assert (
+        service.credentials.resolve(service._secret_id(created.server_id, "token"))
+        == "lower"
+    )
+    service.delete_secret(created.server_id, "TOKEN")
+    assert service.get(created.server_id).secret_environment == {
+        "TOKEN": False,
+        "token": True,
+    }
+
+
+def test_legacy_environment_credential_migration_is_idempotent() -> None:
+    service = registry()
+    created = service.create(request(secret_environment_keys=["TOKEN"]))
+    suffix = hashlib.sha256(b"environment\0token").hexdigest()[:20]
+    legacy_id = f"mcp.{created.server_id}.{suffix}"
+    service.credentials.put(legacy_id, "legacy-value")
+    service._records[created.server_id]["secret_environment_version"] = 1
+    service._write()
+    migrated = registry()
+    assert migrated.get(created.server_id).secret_environment == {"TOKEN": True}
+    assert (
+        migrated.credentials.resolve(migrated._secret_id(created.server_id, "TOKEN"))
+        == "legacy-value"
+    )
+    assert not migrated.credentials.has(legacy_id)
+    migrated.put_secret(created.server_id, "TOKEN", "new-value")
+    assert (
+        registry().credentials.resolve(migrated._secret_id(created.server_id, "TOKEN"))
+        == "new-value"
+    )
+
+
+def test_ambiguous_legacy_credentials_are_not_assigned_to_two_variables() -> None:
+    service = registry()
+    created = service.create(request(secret_environment_keys=["TOKEN", "token"]))
+    suffix = hashlib.sha256(b"environment\0token").hexdigest()[:20]
+    legacy_id = f"mcp.{created.server_id}.{suffix}"
+    service.credentials.put(legacy_id, "cannot-reconstruct-originals")
+    service._records[created.server_id]["secret_environment_version"] = 1
+    service._write()
+    migrated = registry()
+    current = migrated.get(created.server_id)
+    assert current.secret_environment == {"TOKEN": False, "token": False}
+    assert current.enabled is False
+    assert current.last_test_succeeded is None
+    assert migrated.credentials.has(
+        legacy_id
+    )  # Keep the original ciphertext recoverable.
+    migrated.put_secret(created.server_id, "TOKEN", "upper")
+    migrated.put_secret(created.server_id, "token", "lower")
+    assert registry().get(created.server_id).secret_environment == {
+        "TOKEN": True,
+        "token": True,
+    }
+    migrated.delete(created.server_id)
+    assert not migrated.credentials.has(legacy_id)
+
+
+def test_credential_id_migration_keeps_new_values_and_is_atomic(monkeypatch) -> None:
+    credentials = EncryptedCredentialStore()
+    credentials.put("mcp.old", "old-value")
+    credentials.put("mcp.new", "new-value")
+    original_write = credentials._write_tokens
+
+    def fail_write(_tokens):
+        raise CredentialStoreError("synthetic failure")
+
+    monkeypatch.setattr(credentials, "_write_tokens", fail_write)
+    with pytest.raises(CredentialStoreError):
+        credentials.move_many({"mcp.old": "mcp.new"})
+    assert credentials.resolve("mcp.old") == "old-value"
+    assert credentials.resolve("mcp.new") == "new-value"
+    monkeypatch.setattr(credentials, "_write_tokens", original_write)
+    credentials.move_many({"mcp.old": "mcp.new"})
+    assert credentials.resolve("mcp.old") is None
+    assert credentials.resolve("mcp.new") == "new-value"
+
+
+def test_ambiguous_legacy_secret_is_not_resurrected_after_removing_a_key() -> None:
+    service = registry()
+    created = service.create(request(secret_environment_keys=["TOKEN", "token"]))
+    legacy_id = service._legacy_environment_secret_id(created.server_id, "TOKEN")
+    service.credentials.put(legacy_id, "ambiguous-old-value")
+    service._records[created.server_id]["secret_environment_version"] = 1
+    service._write()
+    migrated = registry()
+    migrated.update(
+        created.server_id,
+        McpServerUpdateRequest(
+            **request(secret_environment_keys=["token"]).model_dump(),
+            version=created.version,
+        ),
+    )
+    assert registry().get(created.server_id).secret_environment == {"token": False}
+
+
 def test_production_rejects_process_launch_even_after_approval() -> None:
     service = registry(launch=False)
     created = service.create(request(secret_environment_keys=[]))
@@ -184,6 +363,29 @@ def test_production_rejects_process_launch_even_after_approval() -> None:
     assert error.value.code == "MCP_SANDBOX_REQUIRED"
 
 
+@pytest.mark.parametrize("startup,tool", [(120, 300), (1.5, 2.5)])
+def test_server_timeouts_survive_bridge_adaptation_and_reload(startup, tool) -> None:
+    service = registry()
+    created = service.create(
+        request(
+            secret_environment_keys=[],
+            startup_timeout_seconds=startup,
+            tool_timeout_seconds=tool,
+        )
+    )
+    service.trust(created.server_id, created.command_digest)
+    try:
+        tested = service.test(created.server_id)
+        assert tested.last_test_succeeded is True
+        assert tested.startup_timeout_seconds == startup
+        assert tested.tool_timeout_seconds == tool
+        restored = registry().get(created.server_id)
+        assert restored.startup_timeout_seconds == startup
+        assert restored.tool_timeout_seconds == tool
+    finally:
+        service.shutdown()
+
+
 def test_enable_requires_successful_test_and_update_checks_version() -> None:
     service = registry()
     created = service.create(request(secret_environment_keys=[]))
@@ -307,15 +509,18 @@ def test_lifecycle_operations_are_serialized_and_tool_names_are_isolated() -> No
         service.test(server.server_id)
 
     with ThreadPoolExecutor(max_workers=4) as pool:
-        enabled = list(pool.map(lambda item: service.enable(item.server_id), servers * 2))
+        enabled = list(
+            pool.map(lambda item: service.enable(item.server_id), servers * 2)
+        )
     assert all(item.enabled for item in enabled)
     names = [
-        item.name
-        for item in service.tools.definitions()
-        if item.source == "mcp_server"
+        item.name for item in service.tools.definitions() if item.source == "mcp_server"
     ]
     assert len(names) == len(set(names))
-    assert all(any(name.startswith(f"mcp.{item.server_id}.") for name in names) for item in servers)
+    assert all(
+        any(name.startswith(f"mcp.{item.server_id}.") for name in names)
+        for item in servers
+    )
 
     with ThreadPoolExecutor(max_workers=4) as pool:
         list(pool.map(lambda item: service.disable(item.server_id), servers * 2))

backend/tests/test_mcp_sse_limits.py

@@ -0,0 +1,83 @@
+import json
+from contextlib import closing
+
+import httpx
+import pytest
+
+from app.extensions import mcp
+
+
+class ChunkStream(httpx.SyncByteStream):
+    def __init__(self, chunks):
+        self.chunks = chunks
+        self.bytes_read = 0
+
+    def __iter__(self):
+        for chunk in self.chunks:
+            self.bytes_read += len(chunk)
+            yield chunk
+
+
+def test_sse_rejects_unterminated_line_before_reading_entire_stream(monkeypatch):
+    monkeypatch.setattr(mcp, "MAX_MCP_MESSAGE_BYTES", 1024)
+    stream = ChunkStream([b"x" * 256] * 256)
+    with (
+        closing(httpx.Response(200, stream=stream)) as response,
+        pytest.raises(mcp.McpBridgeError, match="too large"),
+    ):
+        list(mcp._iter_sse(response))
+    assert stream.bytes_read == 1280
+
+
+def test_sse_limits_combined_event_before_partial_line_is_complete(monkeypatch):
+    monkeypatch.setattr(mcp, "MAX_MCP_MESSAGE_BYTES", 32)
+    stream = ChunkStream(
+        [b"data: 123456789\n", b"data: 123456789\n", b"x", b"not-read"]
+    )
+    with (
+        closing(httpx.Response(200, stream=stream)) as response,
+        pytest.raises(mcp.McpBridgeError, match="too large"),
+    ):
+        list(mcp._iter_sse(response))
+    assert stream.bytes_read == 33
+
+
+@pytest.mark.parametrize("separator", [b"\n", b"\r", b"\r\n"])
+@pytest.mark.parametrize("chunk_size", [1, 2, 7, 1024])
+def test_sse_preserves_utf8_and_line_endings_across_chunks(separator, chunk_size):
+    payload = json.dumps(
+        {"jsonrpc": "2.0", "id": 1, "result": {"text": "中文"}}, ensure_ascii=False
+    )
+    wire = b"\xef\xbb\xbf" + separator.join(
+        [
+            b": heartbeat",
+            b"event: message",
+            b"id: replay-1",
+            ("data: " + payload).encode(),
+            b"",
+            b"",
+        ]
+    )
+    stream = ChunkStream(
+        [wire[index : index + chunk_size] for index in range(0, len(wire), chunk_size)]
+    )
+    with closing(httpx.Response(200, stream=stream)) as response:
+        assert list(mcp._iter_sse(response)) == [("message", "replay-1", payload)]
+
+
+def test_sse_event_limit_resets_between_events(monkeypatch):
+    monkeypatch.setattr(mcp, "MAX_MCP_MESSAGE_BYTES", 16)
+    with closing(
+        httpx.Response(200, stream=ChunkStream([b"data: one\n\ndata: two\r\r"]))
+    ) as response:
+        assert list(mcp._iter_sse(response)) == [
+            ("message", None, "one"),
+            ("message", None, "two"),
+        ]
+
+
+def test_sse_preserves_multiline_data_and_final_unterminated_line():
+    with closing(
+        httpx.Response(200, stream=ChunkStream([b"data: first\ndata: last"]))
+    ) as response:
+        assert list(mcp._iter_sse(response)) == [("message", None, "first\nlast")]