_lib_loader.py

"""
Shared helper for configuration_gliner_moe.py and modeling_gliner_moe.py.

transformers' trust_remote_code dynamic-module loader only auto-copies flat,
single-level relative imports (from .x import y where x.py sits directly in
the repo root) -- it does not walk real subpackages referenced via dotted
relative imports like `from .gliner_lib.config import y`, and an absolute
`import gliner_lib` would make its import-checker demand gliner_lib be
pip-installed, which it is not (it is vendored, not published). So gliner_lib
is loaded here via importlib directly from disk instead of any import/from
statement naming it, keeping it invisible to that regex-based scanner, then
registered in sys.modules like a normally-imported package.

Important: transformers copies only the single file it is resolving (e.g.
this file, or configuration_gliner_moe.py) into its own separate dynamic-
modules cache directory -- it does NOT bring the rest of the source directory
along, even when the original source was a local folder rather than a Hub
repo. So __file__ here essentially never points anywhere near an actual
gliner_lib/ directory in practice. Lookup order actually used:
  1. sys.modules cache (already loaded once this process).
  2. Right next to this file, in case that assumption ever does hold.
  3. Any directory already on sys.path that contains a gliner_lib/ folder --
     this is what actually matters for local-directory use: if you are
     loading a local checkout of this repo (not yet pushed to the Hub, or
     pushed but you are pointing at a local clone), do
     `sys.path.insert(0, "<that local directory>")` before calling
     AutoModel.from_pretrained(...) / AutoConfig.from_pretrained(...), and
     this resolves without any network call.
  4. Last resort: snapshot_download(repo_id) to fetch this same Hub repo's
     gliner_lib/ directly. Only works once the repo actually exists on the
     Hub -- by design not used for local-only testing.
"""
import importlib.util
import os
import sys


def load_gliner_lib(this_file, repo_id):
    if "gliner_lib" in sys.modules:
        return sys.modules["gliner_lib"]

    pkg_dir = None

    this_dir = os.path.dirname(os.path.abspath(this_file))
    candidate = os.path.join(this_dir, "gliner_lib")
    if os.path.isdir(candidate):
        pkg_dir = candidate

    if pkg_dir is None:
        for entry in sys.path:
            candidate = os.path.join(entry, "gliner_lib")
            if os.path.isdir(candidate):
                pkg_dir = candidate
                break

    if pkg_dir is None:
        from huggingface_hub import snapshot_download

        downloaded_dir = snapshot_download(repo_id=repo_id, allow_patterns=["gliner_lib/*", "gliner_lib/**/*"])
        candidate = os.path.join(downloaded_dir, "gliner_lib")
        if os.path.isdir(candidate):
            pkg_dir = candidate

    if pkg_dir is None:
        raise ImportError(
            f"Could not locate the vendored gliner_lib package (checked next to {this_file}, "
            f"on sys.path, and in a fresh snapshot_download of {repo_id})."
        )

    parent_dir = os.path.dirname(pkg_dir)
    if parent_dir not in sys.path:
        sys.path.insert(0, parent_dir)

    spec = importlib.util.spec_from_file_location(
        "gliner_lib", os.path.join(pkg_dir, "__init__.py"), submodule_search_locations=[pkg_dir]
    )
    module = importlib.util.module_from_spec(spec)
    sys.modules["gliner_lib"] = module
    spec.loader.exec_module(module)
    return module