| 1 | # SPDX-License-Identifier: Apache-2.0 |
| 2 | # SPDX-FileCopyrightText: Copyright contributors to the vLLM project |
| 3 | import json |
| 4 | import os |
| 5 | |
| 6 | import vllm.envs as envs |
| 7 | from vllm.lora.request import LoRARequest |
| 8 | from vllm.lora.resolver import LoRAResolver, LoRAResolverRegistry |
| 9 | |
| 10 | |
| 11 | class FilesystemResolver(LoRAResolver): |
| 12 | def __init__(self, lora_cache_dir: str): |
| 13 | self.lora_cache_dir = lora_cache_dir |
| 14 | |
| 15 | async def resolve_lora( |
| 16 | self, base_model_name: str, lora_name: str |
| 17 | ) -> LoRARequest | None: |
| 18 | lora_path = os.path.join(self.lora_cache_dir, lora_name) |
| 19 | maybe_lora_request = await self._get_lora_req_from_path( |
| 20 | lora_name, lora_path, base_model_name |
| 21 | ) |
| 22 | return maybe_lora_request |
| 23 | |
| 24 | async def _get_lora_req_from_path( |
| 25 | self, lora_name: str, lora_path: str, base_model_name: str |
| 26 | ) -> LoRARequest | None: |
| 27 | """Builds a LoraRequest pointing to the lora path if it's a valid |
| 28 | LoRA adapter and has a matching base_model_name. |
| 29 | """ |
| 30 | if os.path.exists(lora_path): |
| 31 | adapter_config_path = os.path.join(lora_path, "adapter_config.json") |
| 32 | |
| 33 | if os.path.exists(adapter_config_path): |
| 34 | with open(adapter_config_path) as file: |
| 35 | adapter_config = json.load(file) |
| 36 | if ( |
| 37 | adapter_config["peft_type"] == "LORA" |
| 38 | and adapter_config["base_model_name_or_path"] == base_model_name |
| 39 | ): |
| 40 | lora_request = LoRARequest( |
| 41 | lora_name=lora_name, |
| 42 | lora_int_id=abs(hash(lora_name)), |
| 43 | lora_path=lora_path, |
| 44 | ) |
| 45 | return lora_request |
| 46 | return None |
| 47 | |
| 48 | |
| 49 | def register_filesystem_resolver(): |
| 50 | """Register the filesystem LoRA Resolver with vLLM.""" |
| 51 | lora_cache_dir = envs.VLLM_LORA_RESOLVER_CACHE_DIR |
| 52 | if lora_cache_dir: |
| 53 | if not os.path.exists(lora_cache_dir) or not os.path.isdir(lora_cache_dir): |
| 54 | raise ValueError( |
| 55 | "VLLM_LORA_RESOLVER_CACHE_DIR must be set to a valid directory \ |
| 56 | for Filesystem Resolver plugin to function" |
| 57 | ) |
| 58 | fs_resolver = FilesystemResolver(lora_cache_dir) |
| 59 | LoRAResolverRegistry.register_resolver("Filesystem Resolver", fs_resolver) |
| 60 | |
| 61 | return |