Files
ALwrity/backend/services/llm_providers/huggingface_provider.py
2026-03-11 19:09:27 +05:30

580 lines
21 KiB
Python

"""
Hugging Face Provider Module for ALwrity
This module provides functions for interacting with Hugging Face's Inference Providers API
using the Responses API (beta) which provides a unified interface for model interactions.
Key Features:
- Text response generation with retry logic
- Structured JSON response generation with schema validation
- Comprehensive error handling and logging
- Automatic API key management
- Support for various Hugging Face models via Inference Providers
Best Practices:
1. Use structured output for complex, multi-field responses
2. Keep schemas simple and flat to avoid truncation
3. Set appropriate token limits (8192 for complex outputs)
4. Use low temperature (0.1-0.3) for consistent structured output
5. Implement proper error handling in calling functions
6. Use the Responses API for better compatibility
Usage Examples:
# Text response
result = huggingface_text_response(prompt, temperature=0.7, max_tokens=2048)
# Structured JSON response
schema = {
"type": "object",
"properties": {
"tasks": {
"type": "array",
"items": {"type": "object", "properties": {...}}
}
}
}
result = huggingface_structured_json_response(prompt, schema, temperature=0.2, max_tokens=8192)
Dependencies:
- openai (for Hugging Face Responses API)
- tenacity (for retry logic)
- logging (for debugging)
- json (for fallback parsing)
Author: ALwrity Team
Version: 1.0
Last Updated: January 2025
"""
import os
import sys
from pathlib import Path
import json
import re
from typing import Optional, Dict, Any, List
from dotenv import load_dotenv
# Fix the environment loading path - load from backend directory
current_dir = Path(__file__).parent.parent # services directory
backend_dir = current_dir.parent # backend directory
env_path = backend_dir / '.env'
if env_path.exists():
load_dotenv(env_path)
print(f"Loaded .env from: {env_path}")
else:
# Fallback to current directory
load_dotenv()
print(f"No .env found at {env_path}, using current directory")
from loguru import logger
from utils.logger_utils import get_service_logger
# Use service-specific logger to avoid conflicts
logger = get_service_logger("huggingface_provider")
from tenacity import (
retry,
retry_if_exception,
stop_after_attempt,
wait_random_exponential,
)
try:
from openai import OpenAI
from openai import NotFoundError
OPENAI_AVAILABLE = True
except ImportError:
OPENAI_AVAILABLE = False
NotFoundError = Exception
logger.warn("OpenAI library not available. Install with: pip install openai")
HF_FALLBACK_MODELS = [
"openai/gpt-oss-120b:cerebras",
"moonshotai/Kimi-K2-Instruct-0905:cerebras",
"meta-llama/Llama-3.1-8B-Instruct:cerebras",
"mistralai/Mistral-7B-Instruct-v0.3:cerebras",
]
def _candidate_model_variants(model: str):
"""Yield model ids to try for a single logical model preference."""
if not model:
return
# Try configured model first (supports provider suffixes like ":cerebras")
yield model
# Fallback to base repo id when provider suffix is not recognized by the router
if ":" in model:
base_model = model.split(":", 1)[0]
if base_model:
yield base_model
def _fallback_model_sequence(model: str, fallback_models: Optional[List[str]] = None):
# IMPORTANT: Do not apply implicit global fallback chains.
# Callers must explicitly provide fallback_models when they want multi-model retries.
if fallback_models:
sequence = [model] + fallback_models
else:
sequence = [model]
seen = set()
for preferred_model in sequence:
for candidate in _candidate_model_variants(preferred_model):
if candidate and candidate not in seen:
seen.add(candidate)
yield candidate
def _is_non_retryable_hf_error(exc: Exception) -> bool:
"""Skip retries for deterministic HF failures (e.g., unknown model ids, billing)."""
msg = str(exc).lower()
status = getattr(exc, "status_code", None)
# Non-retryable errors
if isinstance(exc, NotFoundError) or "not found" in msg or "404" in msg:
return True
if status == 402 or "402" in msg or "depleted" in msg or "credits" in msg:
return True
if status == 401 or "unauthorized" in msg or "401" in msg:
return True
if status == 403 or "forbidden" in msg or "403" in msg:
return True
return False
def _should_retry_hf_error(exc: Exception) -> bool:
return not _is_non_retryable_hf_error(exc)
def _classify_hf_error(exc: Exception) -> str:
"""Classify HF failures for actionable logs."""
msg = str(exc).lower()
if any(token in msg for token in ["insufficient", "balance", "quota", "billing", "payment", "402"]):
return "billing_or_quota"
if "unauthorized" in msg or "forbidden" in msg or "401" in msg or "403" in msg:
return "auth_or_permission"
if "not found" in msg or "404" in msg:
return "model_not_found"
return "unknown"
def _hf_error_details(exc: Exception) -> str:
"""Return compact, actionable exception details for logs."""
status = getattr(exc, "status_code", None)
err_type = type(exc).__name__
message = str(exc)
raw_body = getattr(exc, "body", None)
details = f"type={err_type}"
if status is not None:
details += f", status={status}"
if message:
details += f", message={message}"
if raw_body:
details += f", body={raw_body}"
details += f", repr={repr(exc)}"
return details
def get_huggingface_api_key() -> str:
"""Get Hugging Face API key with proper error handling."""
api_key = os.getenv('HF_TOKEN')
if not api_key:
error_msg = "HF_TOKEN environment variable is not set. Please set it in your .env file."
logger.error(error_msg)
raise ValueError(error_msg)
# Validate API key format (basic check)
if not api_key.startswith('hf_'):
error_msg = "HF_TOKEN appears to be invalid. It should start with 'hf_'."
logger.error(error_msg)
raise ValueError(error_msg)
return api_key
@retry(
retry=retry_if_exception(_should_retry_hf_error),
wait=wait_random_exponential(min=1, max=60),
stop=stop_after_attempt(6),
)
def huggingface_text_response(
prompt: str,
model: str = "openai/gpt-oss-120b:cerebras",
fallback_models: Optional[List[str]] = None,
temperature: float = 0.7,
max_tokens: int = 2048,
top_p: float = 0.9,
system_prompt: Optional[str] = None
) -> str:
"""
Generate text response using Hugging Face Inference Providers API.
This function uses the Hugging Face Responses API which provides a unified interface
for model interactions with built-in retry logic and error handling.
Args:
prompt (str): The input prompt for the AI model
model (str): Hugging Face model identifier (default: "openai/gpt-oss-120b:groq")
temperature (float): Controls randomness (0.0-1.0)
max_tokens (int): Maximum tokens in response
top_p (float): Nucleus sampling parameter (0.0-1.0)
system_prompt (str, optional): System instruction for the model
Returns:
str: Generated text response
Raises:
Exception: If API key is missing or API call fails
Best Practices:
- Use appropriate temperature for your use case (0.7 for creative, 0.1-0.3 for factual)
- Set max_tokens based on expected response length
- Use system_prompt to guide model behavior
- Handle errors gracefully in calling functions
Example:
result = huggingface_text_response(
prompt="Write a blog post about AI",
model="openai/gpt-oss-120b:cerebras",
temperature=0.7,
max_tokens=2048,
system_prompt="You are a professional content writer."
)
"""
try:
if not OPENAI_AVAILABLE:
raise ImportError("OpenAI library not available. Install with: pip install openai")
# Get API key with proper error handling
api_key = get_huggingface_api_key()
logger.info(f"🔑 Hugging Face API key loaded: {bool(api_key)} (length: {len(api_key) if api_key else 0})")
if not api_key:
raise Exception("HF_TOKEN not found in environment variables")
# Initialize Hugging Face client
client = OpenAI(
base_url="https://router.huggingface.co/v1",
api_key=api_key,
)
logger.info("✅ Hugging Face client initialized for text response")
# Prepare input for the API
messages = []
# Add system prompt if provided
if system_prompt:
messages.append({
"role": "system",
"content": system_prompt
})
# Add user prompt
messages.append({
"role": "user",
"content": prompt
})
# Add debugging for API call
logger.info(
"Hugging Face text call | model={} | prompt_len={} | temp={} | top_p={} | max_tokens={}",
model,
len(prompt) if isinstance(prompt, str) else '<non-str>',
temperature,
top_p,
max_tokens,
)
logger.info("🚀 Making Hugging Face API call (chat completion)...")
# Add rate limiting to prevent expensive API calls
import time
time.sleep(1) # 1 second delay between API calls
# Call exactly the requested model; no retries, no fallbacks, no variants
response = client.chat.completions.create(
model=model,
messages=messages,
temperature=temperature,
top_p=top_p,
max_tokens=max_tokens
)
# Extract text from response
generated_text = response.choices[0].message.content
# Clean up the response
if generated_text:
# Remove any markdown formatting if present
generated_text = re.sub(r'```[a-zA-Z]*\n?', '', generated_text)
generated_text = re.sub(r'```\n?', '', generated_text)
generated_text = generated_text.strip()
logger.info(f"✅ Hugging Face text response generated successfully (length: {len(generated_text)})")
return generated_text
except Exception as e:
error_class = _classify_hf_error(e)
error_details = _hf_error_details(e)
logger.error(f"❌ Hugging Face text generation failed: {error_details}")
# Extra diagnostics: try to capture raw response if available
if hasattr(e, 'response') and e.response is not None:
logger.error(f"🔍 HF Error Diagnostics:")
logger.error(f" - Status: {e.response.status_code}")
logger.error(f" - Headers: {dict(e.response.headers)}")
try:
body_json = e.response.json()
logger.error(f" - Body JSON: {json.dumps(body_json, indent=2)}")
except Exception:
logger.error(f" - Body Raw: {e.response.text[:1000]}")
else:
logger.error(f"🔍 No HTTP response attached to exception object.")
raise Exception(f"Hugging Face text generation failed: {str(e)}")
@retry(wait=wait_random_exponential(min=1, max=60), stop=stop_after_attempt(6))
def huggingface_structured_json_response(
prompt: str,
schema: Dict[str, Any],
model: str = "openai/gpt-oss-120b:cerebras",
fallback_models: Optional[List[str]] = None,
temperature: float = 0.7,
max_tokens: int = 8192,
system_prompt: Optional[str] = None
) -> Dict[str, Any]:
"""
Generate structured JSON response using Hugging Face Inference Providers API.
This function uses the Hugging Face Responses API with structured output support
to generate JSON responses that match a provided schema.
Args:
prompt (str): The input prompt for the AI model
schema (dict): JSON schema defining the expected output structure
model (str): Hugging Face model identifier (default: "openai/gpt-oss-120b:groq")
temperature (float): Controls randomness (0.0-1.0). Use 0.1-0.3 for structured output
max_tokens (int): Maximum tokens in response. Use 8192 for complex outputs
system_prompt (str, optional): System instruction for the model
Returns:
dict: Parsed JSON response matching the provided schema
Raises:
Exception: If API key is missing or API call fails
Best Practices:
- Keep schemas simple and flat to avoid truncation
- Use low temperature (0.1-0.3) for consistent structured output
- Set max_tokens to 8192 for complex multi-field responses
- Avoid deeply nested schemas with many required fields
- Test with smaller outputs first, then scale up
Example:
schema = {
"type": "object",
"properties": {
"tasks": {
"type": "array",
"items": {
"type": "object",
"properties": {
"title": {"type": "string"},
"description": {"type": "string"}
}
}
}
}
}
result = huggingface_structured_json_response(prompt, schema, temperature=0.2, max_tokens=8192)
"""
try:
if not OPENAI_AVAILABLE:
raise ImportError("OpenAI library not available. Install with: pip install openai")
# Get API key with proper error handling
api_key = get_huggingface_api_key()
logger.info(f"🔑 Hugging Face API key loaded: {bool(api_key)} (length: {len(api_key) if api_key else 0})")
if not api_key:
raise Exception("HF_TOKEN not found in environment variables")
# Initialize OpenAI client with Hugging Face base URL
# Use standard Inference API endpoint
client = OpenAI(
base_url="https://router.huggingface.co/v1",
api_key=api_key,
)
logger.info("✅ Hugging Face client initialized for structured JSON response")
# Prepare input for the API
messages = []
# Add system prompt if provided
if system_prompt:
messages.append({
"role": "system",
"content": system_prompt
})
# Add user prompt with JSON instruction
# For HF models, explicit JSON instruction in prompt is often better than response_format
json_instruction = "Please respond with valid JSON that matches the provided schema."
messages.append({
"role": "user",
"content": f"{prompt}\n\n{json_instruction}"
})
# Add debugging for API call
logger.info(
"Hugging Face structured call | model={} | prompt_len={} | schema_kind={} | temp={} | max_tokens={}",
model,
len(prompt) if isinstance(prompt, str) else '<non-str>',
type(schema).__name__,
temperature,
max_tokens,
)
logger.info("🚀 Making Hugging Face structured API call...")
# Make the API call using standard Chat Completions
logger.info("🚀 Making Hugging Face API call (chat completion)...")
# Add JSON schema to prompt for guidance
json_schema_str = json.dumps(schema, indent=2)
messages[-1]["content"] += f"\n\nJSON Schema:\n{json_schema_str}"
# Add rate limiting to prevent expensive API calls
import time
time.sleep(1) # 1 second delay between API calls
try:
response = None
last_error = None
for candidate_model in _fallback_model_sequence(model, fallback_models):
try:
response = client.chat.completions.create(
model=candidate_model,
messages=messages,
temperature=temperature,
max_tokens=max_tokens,
response_format={"type": "json_object"} # Try to enforce JSON mode if supported
)
if candidate_model != model:
logger.warning("HF structured generation switched to fallback model: {}", candidate_model)
break
except NotFoundError as nf_err:
last_error = nf_err
logger.warning("HF structured model not found: {}. Trying fallback model.", candidate_model)
continue
if response is None:
raise last_error or Exception("Hugging Face structured generation failed: all fallback models failed")
response_text = response.choices[0].message.content
# Clean up response text if needed
response_text = response_text.strip()
if response_text.startswith("```json"):
response_text = response_text[7:]
if response_text.endswith("```"):
response_text = response_text[:-3]
response_text = response_text.strip()
try:
parsed_json = json.loads(response_text)
logger.info("✅ Hugging Face structured JSON response parsed successfully")
return parsed_json
except json.JSONDecodeError as json_err:
logger.error(f"❌ JSON parsing failed: {json_err}")
logger.error(f"Raw response: {response_text}")
# Try to extract JSON from the response using regex
json_match = re.search(r'\{.*\}', response_text, re.DOTALL)
if json_match:
try:
extracted_json = json.loads(json_match.group())
logger.info("✅ JSON extracted using regex fallback")
return extracted_json
except json.JSONDecodeError:
pass
return {"error": "Failed to parse JSON response", "raw_response": response_text}
except Exception as e:
logger.error(f"❌ Hugging Face API call failed: {e}")
# If 422 Unprocessable Entity (often due to response_format not supported), retry without it
if "422" in str(e) or "not supported" in str(e).lower() or isinstance(e, NotFoundError):
logger.info("Retrying without response_format...")
response = None
last_error = None
for candidate_model in _fallback_model_sequence(model, fallback_models):
try:
response = client.chat.completions.create(
model=candidate_model,
messages=messages,
temperature=temperature,
max_tokens=max_tokens
)
if candidate_model != model:
logger.warning("HF structured no-response_format fallback model: {}", candidate_model)
break
except NotFoundError as nf_err:
last_error = nf_err
logger.warning("HF structured model not found (no response_format path): {}", candidate_model)
continue
if response is None:
raise last_error or e
response_text = response.choices[0].message.content
# ... (same parsing logic would apply, simplified here for brevity)
try:
return json.loads(response_text)
except:
# Regex fallback
json_match = re.search(r'\{.*\}', response_text, re.DOTALL)
if json_match:
return json.loads(json_match.group())
return {"error": "Failed to parse JSON response", "raw_response": response_text}
raise e
except Exception as e:
error_msg = str(e) if str(e) else repr(e)
error_type = type(e).__name__
logger.error(f"❌ Hugging Face structured JSON generation failed: {error_type}: {error_msg}")
logger.error(f"❌ Full exception details: {repr(e)}")
import traceback
logger.error(f"❌ Traceback: {traceback.format_exc()}")
raise Exception(f"Hugging Face structured JSON generation failed: {error_type}: {error_msg}")
def get_available_models() -> list:
"""
Get list of available Hugging Face models for text generation.
Returns:
list: List of available model identifiers
"""
return [
"openai/gpt-oss-120b:groq",
"moonshotai/Kimi-K2-Instruct-0905:groq",
"Qwen/Qwen2.5-VL-7B-Instruct",
"meta-llama/Llama-3.1-8B-Instruct:groq",
"microsoft/Phi-3-medium-4k-instruct:groq",
"mistralai/Mistral-7B-Instruct-v0.3:groq"
]
def validate_model(model: str) -> bool:
"""
Validate if a model identifier is supported.
Args:
model (str): Model identifier to validate
Returns:
bool: True if model is supported, False otherwise
"""
available_models = get_available_models()
return model in available_models