Add MCP handler unit tests with mocked Gns3Connector

Tests cover:
- get_nodes_handler: fields filter, invalid fields rejection
- create_node_handler: name passthrough, fields filter, fields validation,
  batch mode inherited template_id, missing project_id
- create_link_handler: compact format, standard format, fields validation
- appliance_get, appliance_install with version
- list_templates: fields filter, invalid field error

tests/api/routes/mcp/conftest.py

@@ -0,0 +1,12 @@
+"""MCP test fixtures."""
+import pytest
+
+
+@pytest.fixture
+def ctx():
+    """Standard gns3_ctx for handlers."""
+    return {
+        "server_url": "http://192.168.1.3:3080",
+        "jwt_token": "test-token",
+        "jwt_username": "admin",
+    }

tests/api/routes/mcp/test_handlers.py

@@ -0,0 +1,192 @@
+"""
+MCP handler unit tests with mocked Gns3Connector.
+
+Tests that handlers correctly transform tool parameters into HTTP calls.
+"""
+import pytest
+from unittest.mock import MagicMock, patch
+
+
+def _mock_conn(json_result=None):
+    """Create a mocked Gns3Connector with base_url and http_call."""
+    conn = MagicMock()
+    conn.base_url = "http://192.168.1.3:3080/v3"
+    conn.http_call.return_value.json.return_value = json_result or {"status": "ok"}
+    return conn
+
+
+@pytest.fixture
+def ctx():
+    return {"server_url": "http://192.168.1.3:3080", "jwt_token": "token", "jwt_username": "admin"}
+
+
+class TestGetNodes:
+
+    def test_fields_filter(self, ctx):
+        from gns3server.api.routes.mcp.nodes import get_nodes_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn([
+                {"node_id": "n1", "name": "R1", "status": "started", "node_type": "qemu", "console": 5000},
+            ])
+            m.return_value = conn
+            result = get_nodes_handler({"project_id": "p1", "fields": ["name", "status"]}, ctx)
+            assert result == {"nodes": [{"name": "R1", "status": "started"}], "count": 1}
+
+    def test_invalid_fields(self, ctx):
+        from gns3server.api.routes.mcp.nodes import get_nodes_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn([])
+            m.return_value = conn
+            result = get_nodes_handler({"project_id": "p1", "fields": "not-a-list"}, ctx)
+            assert "error" in result
+
+
+class TestCreateNode:
+
+    def test_single_passes_name(self, ctx):
+        from gns3server.api.routes.mcp.nodes import create_node_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn({"node_id": "n1", "name": "MyRouter"})
+            m.return_value = conn
+            result = create_node_handler({
+                "project_id": "p1", "template_id": "t1",
+                "name": "MyRouter", "x": 100, "y": 200,
+            }, ctx)
+            conn.http_call.assert_called_with(
+                "post", "http://192.168.1.3:3080/v3/projects/p1/templates/t1",
+                json_data={"x": 100, "y": 200, "compute_id": "local", "name": "MyRouter"},
+            )
+            assert result == {"node_id": "n1", "name": "MyRouter"}
+
+    def test_fields_filter(self, ctx):
+        from gns3server.api.routes.mcp.nodes import create_node_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn({"node_id": "n1", "name": "R1", "status": "started", "node_type": "qemu", "console": 5000})
+            m.return_value = conn
+            result = create_node_handler({
+                "project_id": "p1", "template_id": "t1",
+                "fields": ["node_id", "name"],
+            }, ctx)
+            assert result == {"node_id": "n1", "name": "R1"}
+
+    def test_fields_validation(self, ctx):
+        from gns3server.api.routes.mcp.nodes import create_node_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn()
+            m.return_value = conn
+            result = create_node_handler({
+                "project_id": "p1", "template_id": "t1", "fields": "not-a-list",
+            }, ctx)
+            assert "error" in result
+            assert "fields must be a list" in result["error"]
+            conn.http_call.assert_not_called()
+
+    def test_batch_inherits_template_id(self, ctx):
+        from gns3server.api.routes.mcp.nodes import create_node_handler
+        with patch("gns3server.api.routes.mcp.nodes._get_connector") as m:
+            conn = _mock_conn({"node_id": "n1", "name": "R1"})
+            m.return_value = conn
+            result = create_node_handler({
+                "project_id": "p1", "template_id": "default-tpl",
+                "nodes": [{"name": "R1", "x": 0, "y": 0}],
+            }, ctx)
+            assert result[0]["status"] == "success"
+
+    def test_missing_project_id(self, ctx):
+        from gns3server.api.routes.mcp.nodes import create_node_handler
+        assert create_node_handler({}, ctx) == {"error": "project_id is required"}
+
+
+class TestCreateLink:
+
+    def test_compact_format(self, ctx):
+        from gns3server.api.routes.mcp.links import create_link_handler
+        with patch("gns3server.api.routes.mcp.links._get_connector") as m:
+            conn = _mock_conn({"link_id": "l1", "link_type": "ethernet", "nodes": []})
+            m.return_value = conn
+            result = create_link_handler({
+                "project_id": "p1",
+                "nodes": ["n1", 0, 0, "n2", 0, 0],
+            }, ctx)
+            conn.http_call.assert_called_with(
+                "post", "http://192.168.1.3:3080/v3/projects/p1/links",
+                json_data={
+                    "nodes": [
+                        {"node_id": "n1", "adapter_number": 0, "port_number": 0},
+                        {"node_id": "n2", "adapter_number": 0, "port_number": 0},
+                    ]
+                },
+            )
+
+    def test_standard_format(self, ctx):
+        from gns3server.api.routes.mcp.links import create_link_handler
+        with patch("gns3server.api.routes.mcp.links._get_connector") as m:
+            conn = _mock_conn({"link_id": "l1"})
+            m.return_value = conn
+            result = create_link_handler({
+                "project_id": "p1",
+                "nodes": [
+                    {"node_id": "n1", "adapter_number": 0, "port_number": 0},
+                    {"node_id": "n2", "adapter_number": 0, "port_number": 0},
+                ],
+            }, ctx)
+            assert result["link_id"] == "l1"
+
+    def test_fields_validation(self, ctx):
+        from gns3server.api.routes.mcp.links import create_link_handler
+        with patch("gns3server.api.routes.mcp.links._get_connector") as m:
+            conn = _mock_conn()
+            m.return_value = conn
+            result = create_link_handler({
+                "project_id": "p1", "fields": "bad",
+                "nodes": ["n1", 0, 0, "n2", 0, 0],
+            }, ctx)
+            assert "error" in result
+            assert "fields must be a list" in result["error"]
+            conn.http_call.assert_not_called()
+
+
+class TestAppliance:
+
+    def test_get(self, ctx):
+        from gns3server.api.routes.mcp.appliances import get_appliance_handler
+        with patch("gns3server.api.routes.mcp.appliances._get_connector") as m:
+            conn = _mock_conn({"appliance_id": "a1", "name": "Cisco ISE"})
+            m.return_value = conn
+            result = get_appliance_handler({"appliance_id": "a1"}, ctx)
+            assert result["name"] == "Cisco ISE"
+
+    def test_install_with_version(self, ctx):
+        from gns3server.api.routes.mcp.appliances import install_appliance_handler
+        with patch("gns3server.api.routes.mcp.appliances._get_connector") as m:
+            conn = _mock_conn({"status": "installed"})
+            m.return_value = conn
+            result = install_appliance_handler({
+                "appliance_id": "a1", "version": "2.7.0.356",
+            }, ctx)
+            conn.http_call.assert_called_with(
+                "post", "http://192.168.1.3:3080/v3/appliances/a1/install",
+                params={"version": "2.7.0.356"},
+            )
+
+
+class TestTemplates:
+
+    def test_list_fields(self, ctx):
+        from gns3server.api.routes.mcp.templates import list_templates_handler
+        with patch("gns3server.api.routes.mcp.templates._get_connector") as m:
+            conn = _mock_conn([
+                {"template_id": "t1", "name": "Cisco 7200", "template_type": "dynamips",
+                 "category": "router", "default_name_format": "{name}-{0}"},
+            ])
+            m.return_value = conn
+            result = list_templates_handler({"fields": ["template_id", "name"]}, ctx)
+            assert result["templates"] == [{"template_id": "t1", "name": "Cisco 7200"}]
+
+    def test_list_invalid_field(self, ctx):
+        from gns3server.api.routes.mcp.templates import list_templates_handler
+        with patch("gns3server.api.routes.mcp.templates._get_connector") as m:
+            conn = _mock_conn()
+            m.return_value = conn
+            result = list_templates_handler({"fields": ["does_not_exist"]}, ctx)
+            assert "error" in result