Overview
The settings module contains all backend configuration including server settings, CORS origins, audio processing parameters, OpenAI configuration, and logging setup.
Location: backend/src/config/settings.py
Server Configuration
SERVER_CONFIG = {
"host": "0.0.0.0",
"port": int(os.getenv("PORT", "10000")),
"debug": os.getenv("DEBUG", "false").lower() == "true"
}
Server bind address. 0.0.0.0 makes the server accessible from any network interface.
Server port number. Configurable via PORT environment variable.
Debug mode flag. Set DEBUG=true environment variable to enable. Converts string to boolean.
Example Usage
from config.settings import SERVER_CONFIG
if __name__ == "__main__":
uvicorn.run(
app,
host=SERVER_CONFIG["host"],
port=SERVER_CONFIG["port"],
debug=SERVER_CONFIG["debug"]
)
CORS Origins
CORS_ORIGINS = [
"https://www.langshazam.com",
"https://langshazam.com",
"http://www.langshazam.com",
"http://langshazam.com",
"http://localhost:3000", # For local development
"http://localhost:5173", # For Vite development server
"http://127.0.0.1:3000", # Alternative local development
"http://127.0.0.1:5173" # Alternative Vite development server
]
CORSMiddleware.
Categories
- Production:
langshazam.com (HTTP and HTTPS, with and without www)
- Development:
localhost and 127.0.0.1 on ports 3000 and 5173
Usage
From main.py:28-34:
app.add_middleware(
CORSMiddleware,
allow_origins=CORS_ORIGINS,
allow_credentials=True,
allow_methods=["*"],
allow_headers=["*"],
)
Audio Configuration
AUDIO_CONFIG = {
"min_audio_size": 20000, # Minimum size in bytes
"chunk_size": 128 * 1024, # 128KB chunks
"min_audio_length": 4000, # 4 seconds minimum
"max_audio_length": 15000, # 15 seconds maximum
"audio_bits_per_second": 16000
}
Minimum audio buffer size in bytes before processing. Approximately 1 second of audio at 16 kbps.
WebSocket chunk size in bytes (128KB). Used for streaming audio data.
Minimum audio length in milliseconds (4 seconds). Quality threshold for reliable detection.
Maximum audio length in milliseconds (15 seconds). Prevents excessive processing time.
Audio bitrate in bits per second (16 kbps). Standard bitrate for speech recognition.
Example Usage
from config.settings import AUDIO_CONFIG
MIN_AUDIO_SIZE = AUDIO_CONFIG["min_audio_size"]
if total_size >= MIN_AUDIO_SIZE:
# Process audio
pass
OpenAI Configuration
OPENAI_CONFIG = {
"model": "whisper-1",
"max_concurrent_calls": 3
}
OpenAI Whisper model to use for audio transcription and language detection.
Maximum number of concurrent OpenAI API calls. Additional requests are queued.
Example Usage
from config.settings import OPENAI_CONFIG
processor = AudioProcessor(
api_key=os.getenv("OPENAI_API_KEY"),
max_concurrent_calls=OPENAI_CONFIG["max_concurrent_calls"]
)
response = await client.audio.transcriptions.create(
model=OPENAI_CONFIG["model"],
file=audio_file,
response_format="verbose_json"
)
Logging Configuration
LOGGING_CONFIG = {
"level": "INFO",
"format": "%(asctime)s [%(levelname)s] %(message)s",
"datefmt": "%Y-%m-%d %H:%M:%S"
}
Logging level. Options: DEBUG, INFO, WARNING, ERROR, CRITICAL
format
str
default:"%(asctime)s [%(levelname)s] %(message)s"
Log message format string. Includes timestamp, level, and message.
datefmt
str
default:"%Y-%m-%d %H:%M:%S"
Date/time format for log timestamps.
Example Usage
From main.py:16-22:
logging.basicConfig(
level=getattr(logging, LOGGING_CONFIG["level"]),
format=LOGGING_CONFIG["format"],
datefmt=LOGGING_CONFIG["datefmt"]
)
logger = logging.getLogger(__name__)
Example Output
2026-03-08 10:30:45 [INFO] [a1b2c3d4] WebSocket connection established
2026-03-08 10:30:47 [INFO] [a1b2c3d4] Processing audio data of size: 24500 bytes
2026-03-08 10:30:49 [INFO] [a1b2c3d4] Language detected: en in 2.34s
Environment Variables
The following environment variables are used:
Server port number. Used by SERVER_CONFIG.
Debug mode flag. Set to "true" to enable. Used by SERVER_CONFIG.
OpenAI API key for Whisper transcription. Required for audio processing.
Example .env File
PORT=10000
DEBUG=false
OPENAI_API_KEY=sk-...
Type Hints
from typing import Dict, Any
SERVER_CONFIG: Dict[str, Any] = {...}
CORS_ORIGINS: List[str] = [...]
AUDIO_CONFIG: Dict[str, int] = {...}
OPENAI_CONFIG: Dict[str, Any] = {...}
LOGGING_CONFIG: Dict[str, str] = {...}
Dependencies
import os
from typing import Dict, Any
Best Practices
Adding New Settings
- Group related settings in dictionaries
- Use descriptive names with units in comments
- Provide sensible defaults
- Use environment variables for deployment-specific values
- Document purpose and valid values
Environment Variable Patterns
# String with default
value = os.getenv("VAR_NAME", "default_value")
# Integer with default
value = int(os.getenv("VAR_NAME", "10000"))
# Boolean with default
value = os.getenv("VAR_NAME", "false").lower() == "true"
# Required (no default)
value = os.getenv("REQUIRED_VAR") # Returns None if not set
