[llvm-advisor] add web server API infrastructure

- implement HTTP server with RESTful API endpoints

- add base API classes

Author: miguelcsx

llvm/tools/llvm-advisor/tools/__init__.py

@@ -0,0 +1,7 @@
+# ===----------------------------------------------------------------------===//
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===//

llvm/tools/llvm-advisor/tools/webserver/__init__.py

@@ -0,0 +1,7 @@
+# ===----------------------------------------------------------------------===//
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===//

llvm/tools/llvm-advisor/tools/webserver/api/__init__.py

@@ -0,0 +1,8 @@
+# ===----------------------------------------------------------------------===//
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===//
+

llvm/tools/llvm-advisor/tools/webserver/api/base.py

@@ -0,0 +1,55 @@
+# ===----------------------------------------------------------------------===//
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===//
+
+import json
+from abc import ABC, abstractmethod
+from typing import Dict, Any, Optional
+
+
+class BaseEndpoint(ABC):
+    def __init__(self, data_dir: str, collector):
+        self.data_dir = data_dir
+        self.collector = collector
+        self._cache = {}
+
+    @abstractmethod
+    def handle(self, path_parts: list, query_params: Dict[str, list]) -> Dict[str, Any]:
+        pass
+
+    def get_compilation_units(self):
+        if "units" not in self._cache:
+            self._cache["units"] = self.collector.discover_compilation_units(
+                self.data_dir
+            )
+        return self._cache["units"]
+
+    def get_parsed_data(self):
+        if "parsed_data" not in self._cache:
+            self._cache["parsed_data"] = self.collector.parse_all_units(self.data_dir)
+        return self._cache["parsed_data"]
+
+    def clear_cache(self):
+        self._cache.clear()
+
+
+class APIResponse:
+    @staticmethod
+    def success(data: Any, status: int = 200) -> Dict[str, Any]:
+        return {"success": True, "data": data, "status": status}
+
+    @staticmethod
+    def error(message: str, status: int = 400) -> Dict[str, Any]:
+        return {"success": False, "error": message, "status": status}
+
+    @staticmethod
+    def not_found(resource: str) -> Dict[str, Any]:
+        return APIResponse.error(f"{resource} not found", 404)
+
+    @staticmethod
+    def invalid_request(message: str) -> Dict[str, Any]:
+        return APIResponse.error(f"Invalid request: {message}", 400)

llvm/tools/llvm-advisor/tools/webserver/api/health.py

@@ -0,0 +1,43 @@
+# ===----------------------------------------------------------------------===//
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===//
+
+import os
+from typing import Dict, Any
+from .base import BaseEndpoint, APIResponse
+
+
+class HealthEndpoint(BaseEndpoint):
+    """GET /api/health - System health and data directory status"""
+
+    def handle(self, path_parts: list, query_params: Dict[str, list]) -> Dict[str, Any]:
+        data_dir_exists = os.path.exists(self.data_dir)
+
+        # Count units and files if data directory exists
+        unit_count = 0
+        file_count = 0
+
+        if data_dir_exists:
+            try:
+                units = self.get_compilation_units()
+                unit_count = len(units)
+                file_count = sum(
+                    sum(len(files) for files in unit.artifacts.values())
+                    for unit in units
+                )
+            except Exception:
+                pass
+
+        health_data = {
+            "status": "healthy" if data_dir_exists else "no_data",
+            "data_dir": self.data_dir,
+            "data_dir_exists": data_dir_exists,
+            "compilation_units": unit_count,
+            "total_files": file_count,
+        }
+
+        return APIResponse.success(health_data)