llama-stack/llama_toolchain/safety/shields/llama_guard.py
2024-07-23 08:32:33 -07:00

252 lines
8 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import re
from string import Template
from typing import List, Optional
import torch
from llama_models.llama3_1.api.datatypes import Message, Role
from transformers import AutoModelForCausalLM, AutoTokenizer
from .base import CANNED_RESPONSE_TEXT, OnViolationAction, ShieldBase, ShieldResponse
from llama_toolchain.safety.api.datatypes import * # noqa: F403
SAFE_RESPONSE = "safe"
_INSTANCE = None
CAT_VIOLENT_CRIMES = "Violent Crimes"
CAT_NON_VIOLENT_CRIMES = "Non-Violent Crimes"
CAT_SEX_CRIMES = "Sex Crimes"
CAT_CHILD_EXPLOITATION = "Child Exploitation"
CAT_DEFAMATION = "Defamation"
CAT_SPECIALIZED_ADVICE = "Specialized Advice"
CAT_PRIVACY = "Privacy"
CAT_INTELLECTUAL_PROPERTY = "Intellectual Property"
CAT_INDISCRIMINATE_WEAPONS = "Indiscriminate Weapons"
CAT_HATE = "Hate"
CAT_SELF_HARM = "Self-Harm"
CAT_SEXUAL_CONTENT = "Sexual Content"
CAT_ELECTIONS = "Elections"
CAT_CODE_INTERPRETER_ABUSE = "Code Interpreter Abuse"
SAFETY_CATEGORIES_TO_CODE_MAP = {
CAT_VIOLENT_CRIMES: "S1",
CAT_NON_VIOLENT_CRIMES: "S2",
CAT_SEX_CRIMES: "S3",
CAT_CHILD_EXPLOITATION: "S4",
CAT_DEFAMATION: "S5",
CAT_SPECIALIZED_ADVICE: "S6",
CAT_PRIVACY: "S7",
CAT_INTELLECTUAL_PROPERTY: "S8",
CAT_INDISCRIMINATE_WEAPONS: "S9",
CAT_HATE: "S10",
CAT_SELF_HARM: "S11",
CAT_SEXUAL_CONTENT: "S12",
CAT_ELECTIONS: "S13",
CAT_CODE_INTERPRETER_ABUSE: "S14",
}
DEFAULT_LG_V3_SAFETY_CATEGORIES = [
CAT_VIOLENT_CRIMES,
CAT_NON_VIOLENT_CRIMES,
CAT_SEX_CRIMES,
CAT_CHILD_EXPLOITATION,
CAT_DEFAMATION,
CAT_SPECIALIZED_ADVICE,
CAT_PRIVACY,
CAT_INTELLECTUAL_PROPERTY,
CAT_INDISCRIMINATE_WEAPONS,
CAT_HATE,
CAT_SELF_HARM,
CAT_SEXUAL_CONTENT,
CAT_ELECTIONS,
CAT_CODE_INTERPRETER_ABUSE,
]
PROMPT_TASK = "Task: Check if there is unsafe content in '$agent_type' messages in conversations according our safety policy with the below categories."
SAFETY_CATEGORIES = """
<BEGIN UNSAFE CONTENT CATEGORIES>
$categories
<END UNSAFE CONTENT CATEGORIES>
"""
PROMPT_CONVERSATION = """
<BEGIN CONVERSATION>
$conversations
<END CONVERSATION>
"""
PROMPT_INSTRUCTIONS = """
Provide your safety assessment for ONLY THE LAST $agent_type message in the above conversation:
- First line must read 'safe' or 'unsafe'.
- If unsafe, a second line must include a comma-separated list of violated categories."""
PROMPT_TEMPLATE = Template(
f"{PROMPT_TASK}{SAFETY_CATEGORIES}{PROMPT_CONVERSATION}{PROMPT_INSTRUCTIONS}"
)
class LlamaGuardShield(ShieldBase):
@staticmethod
def instance(
on_violation_action=OnViolationAction.RAISE,
model_dir: str = None,
excluded_categories: List[str] = None,
disable_input_check: bool = False,
disable_output_check: bool = False,
) -> "LlamaGuardShield":
global _INSTANCE
if _INSTANCE is None:
_INSTANCE = LlamaGuardShield(
on_violation_action,
model_dir,
excluded_categories,
disable_input_check,
disable_output_check,
)
return _INSTANCE
def __init__(
self,
on_violation_action: OnViolationAction = OnViolationAction.RAISE,
model_dir: str = None,
excluded_categories: List[str] = None,
disable_input_check: bool = False,
disable_output_check: bool = False,
):
super().__init__(on_violation_action)
dtype = torch.bfloat16
assert model_dir is not None, "Llama Guard model_dir is None"
if excluded_categories is None:
excluded_categories = []
assert len(excluded_categories) == 0 or all(
x in SAFETY_CATEGORIES_TO_CODE_MAP.values() for x in excluded_categories
), "Invalid categories in excluded categories. Expected format is ['S1', 'S2', ..]"
self.device = "cuda"
self.excluded_categories = excluded_categories
self.disable_input_check = disable_input_check
self.disable_output_check = disable_output_check
# load model
torch_dtype = torch.bfloat16
self.tokenizer = AutoTokenizer.from_pretrained(model_dir)
self.model = AutoModelForCausalLM.from_pretrained(
model_dir, torch_dtype=torch_dtype, device_map=self.device
)
def get_shield_type(self) -> ShieldType:
return BuiltinShield.llama_guard
def check_unsafe_response(self, response: str) -> Optional[str]:
match = re.match(r"^unsafe\n(.*)$", response)
if match:
# extracts the unsafe code
extracted = match.group(1)
return extracted
return None
def get_safety_categories(self) -> List[str]:
excluded_categories = self.excluded_categories
if set(excluded_categories) == set(SAFETY_CATEGORIES_TO_CODE_MAP.values()):
excluded_categories = []
categories = []
for cat in DEFAULT_LG_V3_SAFETY_CATEGORIES:
cat_code = SAFETY_CATEGORIES_TO_CODE_MAP[cat]
if cat_code in excluded_categories:
continue
categories.append(f"{cat_code}: {cat}.")
return categories
def build_prompt(self, messages: List[Message]) -> str:
categories = self.get_safety_categories()
categories_str = "\n".join(categories)
conversations_str = "\n\n".join(
[f"{m.role.capitalize()}: {m.content}" for m in messages]
)
return PROMPT_TEMPLATE.substitute(
agent_type=messages[-1].role.capitalize(),
categories=categories_str,
conversations=conversations_str,
)
def get_shield_response(self, response: str) -> ShieldResponse:
if response == SAFE_RESPONSE:
return ShieldResponse(
shield_type=BuiltinShield.llama_guard, is_violation=False
)
unsafe_code = self.check_unsafe_response(response)
if unsafe_code:
unsafe_code_list = unsafe_code.split(",")
if set(unsafe_code_list).issubset(set(self.excluded_categories)):
return ShieldResponse(
shield_type=BuiltinShield.llama_guard, is_violation=False
)
return ShieldResponse(
shield_type=BuiltinShield.llama_guard,
is_violation=True,
violation_type=unsafe_code,
violation_return_message=CANNED_RESPONSE_TEXT,
)
raise ValueError(f"Unexpected response: {response}")
async def run(self, messages: List[Message]) -> ShieldResponse:
if self.disable_input_check and messages[-1].role == Role.user.value:
return ShieldResponse(
shield_type=BuiltinShield.llama_guard, is_violation=False
)
elif self.disable_output_check and messages[-1].role == Role.assistant.value:
return ShieldResponse(
shield_type=BuiltinShield.llama_guard,
is_violation=False,
)
else:
prompt = self.build_prompt(messages)
llama_guard_input = {
"role": "user",
"content": prompt,
}
input_ids = self.tokenizer.apply_chat_template(
[llama_guard_input], return_tensors="pt", tokenize=True
).to(self.device)
prompt_len = input_ids.shape[1]
output = self.model.generate(
input_ids=input_ids,
max_new_tokens=20,
output_scores=True,
return_dict_in_generate=True,
pad_token_id=0,
)
generated_tokens = output.sequences[:, prompt_len:]
response = self.tokenizer.decode(
generated_tokens[0], skip_special_tokens=True
)
response = response.strip()
shield_response = self.get_shield_response(response)
return shield_response