v1.0

plugins/__init__.py

@@ -0,0 +1,78 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import logging
+from collections.abc import Callable
+from typing import Any
+
+import vllm.envs as envs
+
+logger = logging.getLogger(__name__)
+
+# Default plugins group will be loaded in all processes(process0, engine core
+# process and worker processes)
+DEFAULT_PLUGINS_GROUP = "vllm.general_plugins"
+# IO processor plugins group will be loaded in process0 only
+IO_PROCESSOR_PLUGINS_GROUP = "vllm.io_processor_plugins"
+# Platform plugins group will be loaded in all processes when
+# `vllm.platforms.current_platform` is called and the value not initialized,
+PLATFORM_PLUGINS_GROUP = "vllm.platform_plugins"
+
+# make sure one process only loads plugins once
+plugins_loaded = False
+
+
+def load_plugins_by_group(group: str) -> dict[str, Callable[[], Any]]:
+    from importlib.metadata import entry_points
+
+    allowed_plugins = envs.VLLM_PLUGINS
+
+    discovered_plugins = entry_points(group=group)
+    if len(discovered_plugins) == 0:
+        logger.debug("No plugins for group %s found.", group)
+        return {}
+
+    # Check if the only discovered plugin is the default one
+    is_default_group = group == DEFAULT_PLUGINS_GROUP
+    # Use INFO for non-default groups and DEBUG for the default group
+    log_level = logger.debug if is_default_group else logger.info
+
+    log_level("Available plugins for group %s:", group)
+    for plugin in discovered_plugins:
+        log_level("- %s -> %s", plugin.name, plugin.value)
+
+    if allowed_plugins is None:
+        log_level(
+            "All plugins in this group will be loaded. "
+            "Set `VLLM_PLUGINS` to control which plugins to load."
+        )
+
+    plugins = dict[str, Callable[[], Any]]()
+    for plugin in discovered_plugins:
+        if allowed_plugins is None or plugin.name in allowed_plugins:
+            if allowed_plugins is not None:
+                log_level("Loading plugin %s", plugin.name)
+
+            try:
+                func = plugin.load()
+                plugins[plugin.name] = func
+            except Exception:
+                logger.exception("Failed to load plugin %s", plugin.name)
+
+    return plugins
+
+
+def load_general_plugins():
+    """WARNING: plugins can be loaded for multiple times in different
+    processes. They should be designed in a way that they can be loaded
+    multiple times without causing issues.
+    """
+    global plugins_loaded
+    if plugins_loaded:
+        return
+    plugins_loaded = True
+
+    plugins = load_plugins_by_group(group=DEFAULT_PLUGINS_GROUP)
+    # general plugins, we only need to execute the loaded functions
+    for func in plugins.values():
+        func()