fix: remove server (sse) retry rules

src/mcp_scan/MCPScanner.py

@@ -12,7 +12,7 @@
 from httpx import HTTPStatusError
 
 from mcp_scan.direct_scanner import direct_scan, is_direct_scan
-from mcp_scan.mcp_client import check_server_with_timeout, scan_mcp_config_file
+from mcp_scan.mcp_client import check_server, scan_mcp_config_file
 from mcp_scan.models import (
     Issue,
     RemoteServer,
@@ -207,9 +207,7 @@ async def scan_server(self, server: ServerScanResult) -> ServerScanResult:
         logger.info("Scanning server: %s", server.name)
         result = server.clone()
         try:
-            result.signature = await check_server_with_timeout(
-                server.server, self.server_timeout, self.suppress_mcpserver_io
-            )
+            result.signature = await check_server(server.server, self.server_timeout, self.suppress_mcpserver_io)
             logger.debug(
                 "Server %s has %d prompts, %d resources, %d resouce templates,  %d tools",
                 server.name,

src/mcp_scan/mcp_client.py

@@ -3,9 +3,11 @@
 import os
 import shutil
 import subprocess
+import sys
 from contextlib import asynccontextmanager
 from pathlib import Path
-from typing import AsyncContextManager  # noqa: UP035
+from typing import AsyncContextManager, Literal  # noqa: UP035
+from urllib.parse import urlparse
 
 import pyjson5
 from mcp import ClientSession, StdioServerParameters
@@ -90,7 +92,7 @@ def get_client(
         raise ValueError(f"Invalid server config: {server_config}")
 
 
-async def check_server(
+async def _check_server_pass(
     server_config: StdioServer | RemoteServer | StaticToolsServer,
     timeout: int,
     suppress_mcpserver_io: bool,
@@ -166,37 +168,65 @@ async def _check_server(verbose: bool) -> ServerSignature:
     return await _check_server(verbose=not suppress_mcpserver_io)
 
 
-async def check_server_with_timeout(
+async def check_server(
     server_config: StdioServer | RemoteServer | StaticToolsServer,
     timeout: int,
     suppress_mcpserver_io: bool,
 ) -> ServerSignature:
     logger.debug("Checking server with timeout: %s seconds", timeout)
-    try_sse = False
 
-    if isinstance(server_config, RemoteServer) and server_config.type is None:
-        server_config.type = "http"
-        logger.debug("Remote server with no type, trying http")
-        try_sse = True
-
-    try:
-        result = await asyncio.wait_for(check_server(server_config, timeout, suppress_mcpserver_io), timeout)
+    if not isinstance(server_config, RemoteServer):
+        result = await asyncio.wait_for(_check_server_pass(server_config, timeout, suppress_mcpserver_io), timeout)
         logger.debug("Server check completed within timeout")
         return result
-    except asyncio.TimeoutError:
-        if not try_sse:
-            raise
+    else:
+        logger.debug(f"Remote server with url: {server_config.url}, type: {server_config.type or 'none'}")
+        strategy: list[tuple[Literal["sse", "http"], str]] = []
+        url_path = urlparse(server_config.url).path
+        has_sse_in_url = url_path.endswith("/sse")
+        if has_sse_in_url:
+            url_with_sse = server_config.url
+            url_without_sse = server_config.url.replace("/sse", "")
         else:
-            logger.debug("Scan with HTTP failed, retrying with SSE")
+            url_with_sse = server_config.url + "/sse"
+            url_without_sse = server_config.url
 
-    server_config.type = "sse"
-    logger.debug("Remote server with no type, trying sse")
-    try:
-        result = await asyncio.wait_for(check_server(server_config, timeout, suppress_mcpserver_io), timeout)
-        logger.debug("Server check completed within timeout")
-        return result
-    except asyncio.TimeoutError:
-        raise
+        if server_config.type == "http" or server_config.type is None:
+            strategy.append(("http", url_without_sse))
+            strategy.append(("http", url_with_sse))
+            strategy.append(("sse", url_with_sse))
+            strategy.append(("sse", url_without_sse))
+        else:
+            strategy.append(("sse", url_with_sse))
+            strategy.append(("sse", url_without_sse))
+            strategy.append(("http", url_without_sse))
+            strategy.append(("http", url_with_sse))
+
+        exceptions: list[Exception] = []
+        for protocol, url in strategy:
+            try:
+                server_config.type = protocol
+                server_config.url = url
+                logger.debug(f"Trying {protocol} with url: {url}")
+                result = await asyncio.wait_for(
+                    _check_server_pass(server_config, timeout, suppress_mcpserver_io), timeout
+                )
+                logger.debug("Server check completed within timeout")
+                return result
+            except asyncio.TimeoutError as e:
+                logger.debug("Server check timed out")
+                exceptions.append(e)
+                continue
+            except Exception as e:
+                logger.debug("Server check failed")
+                exceptions.append(e)
+                continue
+
+        # if python 3.11 or higher, use ExceptionGroup
+        if sys.version_info >= (3, 11):
+            raise ExceptionGroup("Could not connect to remote server", exceptions)  # noqa: F821
+        else:
+            raise Exception("Could not connect to remote server")
 
 
 async def scan_mcp_config_file(path: str) -> MCPConfig:

tests/unit/test_config_scan.py

@@ -16,7 +16,7 @@
 )
 from pytest_lazy_fixtures import lf
 
-from mcp_scan.mcp_client import check_server, check_server_with_timeout, scan_mcp_config_file
+from mcp_scan.mcp_client import check_server, scan_mcp_config_file
 from mcp_scan.models import StdioServer, UnknownMCPConfig
 
 
@@ -111,7 +111,7 @@ async def test_math_server():
     path = "tests/mcp_servers/configs_files/math_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Math":
             assert len(signature.prompts) == 1
             assert len(signature.resources) == 0
@@ -129,7 +129,7 @@ async def test_all_server():
     path = "tests/mcp_servers/configs_files/all_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Math":
             assert len(signature.prompts) == 1
             assert len(signature.resources) == 0
@@ -152,7 +152,7 @@ async def test_weather_server():
     path = "tests/mcp_servers/configs_files/weather_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Weather":
             assert {t.name for t in signature.tools} == {"weather"}
             assert {p.name for p in signature.prompts} == {"good_morning"}

tests/unit/test_control_server.py

@@ -284,7 +284,7 @@ async def test_get_servers_from_path_sets_parse_error_and_uploads_payload():
 @pytest.mark.asyncio
 async def test_scan_server_sets_http_status_error_and_uploads_payload():
     """
-    Patch MCPScanner to return a server, then make check_server_with_timeout raise HTTPStatusError and
+    Patch MCPScanner to return a server, then make check_server raise HTTPStatusError and
     ensure the server-level error message "server returned HTTP status code" is included on upload.
     """
 
@@ -296,7 +296,7 @@ def get_servers(self):
         patch.object(sys.modules["mcp_scan.MCPScanner"], "scan_mcp_config_file", return_value=DummyCfg()),
         patch.object(
             sys.modules["mcp_scan.MCPScanner"],
-            "check_server_with_timeout",
+            "check_server",
             side_effect=httpx.HTTPStatusError("bad", request=None, response=None),
         ),
         patch("mcp_scan.upload.get_user_info") as mock_get_user_info,
@@ -329,7 +329,7 @@ def get_servers(self):
 @pytest.mark.asyncio
 async def test_scan_server_sets_could_not_start_error_and_uploads_payload():
     """
-    Patch MCPScanner to return a server, then make check_server_with_timeout raise a generic Exception and
+    Patch MCPScanner to return a server, then make check_server raise a generic Exception and
     ensure the server-level error message "could not start server" is included on upload.
     """
 
@@ -339,9 +339,7 @@ def get_servers(self):
 
     with (
         patch.object(sys.modules["mcp_scan.MCPScanner"], "scan_mcp_config_file", return_value=DummyCfg()),
-        patch.object(
-            sys.modules["mcp_scan.MCPScanner"], "check_server_with_timeout", side_effect=Exception("spawn failed")
-        ),
+        patch.object(sys.modules["mcp_scan.MCPScanner"], "check_server", side_effect=Exception("spawn failed")),
         patch("mcp_scan.upload.get_user_info") as mock_get_user_info,
     ):
         mock_get_user_info.return_value = ScanUserInfo()
@@ -491,7 +489,7 @@ def get_servers(self):
 
     with (
         patch.object(sys.modules["mcp_scan.MCPScanner"], "scan_mcp_config_file", return_value=DummyCfg()),
-        patch.object(sys.modules["mcp_scan.MCPScanner"], "check_server_with_timeout", return_value=None),
+        patch.object(sys.modules["mcp_scan.MCPScanner"], "check_server", return_value=None),
     ):
         async with MCPScanner(files=["/dummy/path"]) as scanner:
             result = await scanner.scan_path("/dummy/path", inspect_only=True)
@@ -527,7 +525,7 @@ def get_servers(self):
 
     with (
         patch.object(sys.modules["mcp_scan.MCPScanner"], "scan_mcp_config_file", return_value=DummyCfg()),
-        patch.object(sys.modules["mcp_scan.MCPScanner"], "check_server_with_timeout", return_value=None),
+        patch.object(sys.modules["mcp_scan.MCPScanner"], "check_server", return_value=None),
     ):
         async with MCPScanner(files=["/dummy/path"]) as scanner:
             result = await scanner.scan_path("/dummy/path", inspect_only=True)

tests/unit/test_mcp_client.py

@@ -16,7 +16,7 @@
 )
 from pytest_lazy_fixtures import lf
 
-from mcp_scan.mcp_client import check_server, check_server_with_timeout, scan_mcp_config_file
+from mcp_scan.mcp_client import _check_server_pass, check_server, scan_mcp_config_file
 from mcp_scan.models import StdioServer
 
 
@@ -91,7 +91,7 @@ async def __aexit__(self, exc_type, exc_val, exc_tb):
     # Test function with mocks
     with patch("mcp_scan.mcp_client.ClientSession", MockClientSession):
         server = StdioServer(command="mcp", args=["run", "some_file.py"])
-        signature = await check_server(server, 2, True)
+        signature = await _check_server_pass(server, 2, True)
 
     # Verify the results
     assert len(signature.prompts) == 2
@@ -104,7 +104,7 @@ async def test_math_server():
     path = "tests/mcp_servers/configs_files/math_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Math":
             assert len(signature.prompts) == 1
             assert len(signature.resources) == 0
@@ -122,7 +122,7 @@ async def test_all_server():
     path = "tests/mcp_servers/configs_files/all_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Math":
             assert len(signature.prompts) == 1
             assert len(signature.resources) == 0
@@ -145,9 +145,27 @@ async def test_weather_server():
     path = "tests/mcp_servers/configs_files/weather_config.json"
     servers = (await scan_mcp_config_file(path)).get_servers()
     for name, server in servers.items():
-        signature = await check_server_with_timeout(server, 5, False)
+        signature = await check_server(server, 5, False)
         if name == "Weather":
             assert {t.name for t in signature.tools} == {"weather"}
             assert {p.name for p in signature.prompts} == {"good_morning"}
             assert {r.name for r in signature.resources} == {"weathers"}
             assert {rt.name for rt in signature.resource_templates} == {"weather_description"}
+
+
+@pytest.fixture
+def remote_mcp_server_just_url():
+    return """
+    {
+        "mcpServers": {
+            "remote": {
+                "url": "http://localhost:8000"
+            }
+        }
+    }
+    """
+
+
+@pytest.mark.asyncio
+async def test_parse_server():
+    pass