support imports in pushed python code

py/src/braintrust/cli/push.py

@@ -1,5 +1,7 @@
 """Implements the braintrust push subcommand."""
 
+import importlib.abc
+import importlib.machinery
 import importlib.metadata
 import importlib.util
 import inspect
@@ -71,19 +73,63 @@ def _check_uv():
         )
 
 
-def _execute_module(file: str):
-    spec = importlib.util.spec_from_file_location("unused", file)
-    if spec is None or spec.loader is None:
-        raise ValueError(f"Failed to load module from {file}")
-    module = importlib.util.module_from_spec(spec)
-    spec.loader.exec_module(module)
+class _ProjectRootImporter(importlib.abc.MetaPathFinder):
+    """An importer that only resolves top-level modules from the project root and their submodules,
+    and collects the source files of all imported modules.
+    """
+
+    def __init__(self) -> None:
+        self._project_root, self._path_rest = sys.path[0], sys.path[1:]
+        self._sources = []
+
+    def _under_project_root(self, path: List[str]) -> bool:
+        """Returns true if all paths in `path` are under the project root."""
+        return all(p.startswith(self._project_root) for p in path)
+
+    def _under_rest(self, path: List[str]) -> bool:
+        """Returns true if any path in `path` is under one of the remaining paths in `sys.path`."""
+        return any(p.startswith(pr) for p in path for pr in self._path_rest)
+
+    def find_spec(self, fullname, path, target=None):
+        if path is None:
+            # Resolve top-level modules only from the project root.
+            path = [self._project_root]
+        elif not self._under_project_root(path) or self._under_rest(path):
+            # Defer paths that are not under the project root or covered by another sys.path entry
+            # to the subsequent importers.
+            return None
+        spec = importlib.machinery.PathFinder.find_spec(fullname, path, target)
+        if spec is not None and spec.origin is not None:
+            self._sources.append(spec.origin)
+        return spec
+
+    def sources(self) -> List[str]:
+        return self._sources
+
+
+def _import_module(name: str, path: str) -> List[str]:
+    """Imports the module and returns the list of source files
+    of all modules imported in the process.
+
+    Args:
+        name: The fully qualified name of the module to import.
+        path: The absolute path to the module to import.
+
+    Returns:
+        A list of absolute paths to source files of all modules imported in the process.
+    """
+    importer = _ProjectRootImporter()
+    sys.meta_path.insert(0, importer)
+
+    importlib.import_module(name)
+    return importer.sources()
 
 
 def _py_version() -> str:
     return f"{sys.version_info.major}.{sys.version_info.minor}"
 
 
-def _upload_bundle(file: str, requirements: Optional[str]) -> str:
+def _upload_bundle(entry_module_name: str, sources: List[str], requirements: Optional[str]) -> str:
     _check_uv()
 
     resp = proxy_conn().post_json(
@@ -153,7 +199,9 @@ def _upload_bundle(file: str, requirements: Optional[str]) -> str:
                     if os.path.isfile(path):
                         arcname = os.path.join(arcdirpath, name)
                         zf.write(path, arcname)
-            zf.write(file, "register.py")
+            for source in sources:
+                zf.write(source, os.path.relpath(source))
+            zf.writestr("register.py", f"import {entry_module_name} as _\n")
         with open(os.path.join(td, "pkg.zip"), "rb") as zf:
             requests.put(bundle_upload_url, data=zf.read()).raise_for_status()
 
@@ -251,12 +299,19 @@ def run(args):
         app_url=args.app_url,
     )
 
-    _execute_module(args.file)
+    if sys.path[0] != os.getcwd():
+        raise ValueError(
+            f"The current working directory ({os.getcwd()}) is not the project root. "
+            "Please run the push command from the project root."
+        )
+    path = os.path.abspath(args.file)
+    module_name = re.sub(".py$", "", re.sub("/", ".", os.path.relpath(path)))
+    sources = _import_module(module_name, path)
 
     project_ids = _ProjectIdCache()
     functions: List[Dict[str, Any]] = []
     if len(global_.functions) > 0:
-        bundle_id = _upload_bundle(args.file, args.requirements)
+        bundle_id = _upload_bundle(module_name, sources, args.requirements)
         _collect_function_function_defs(project_ids, functions, bundle_id, args.if_exists)
     if len(global_.prompts) > 0:
         _collect_prompt_function_defs(project_ids, functions, args.if_exists)