Deepgram SDK Patterns

Overview

Production-ready patterns for Deepgram SDK integration with proper error handling, typing, and structure.

Prerequisites

• Completed deepgram-install-auth setup
• Familiarity with async/await patterns
• Understanding of error handling best practices

Instructions

Step 1: Create Type-Safe Client Singleton

Implement a singleton pattern for the Deepgram client.

Step 2: Add Robust Error Handling

Wrap all API calls with proper error handling and logging.

Step 3: Implement Response Validation

Validate API responses before processing.

Step 4: Add Retry Logic

Implement exponential backoff for transient failures.

Output

• Type-safe client singleton
• Robust error handling with structured logging
• Automatic retry with exponential backoff
• Runtime validation for API responses

Error Handling

Error	Cause	Solution
Type Mismatch	Incorrect response shape	Add runtime validation
Client Undefined	Singleton not initialized	Call init() before use
Memory Leak	Multiple client instances	Use singleton pattern
Timeout	Large audio file	Increase timeout settings

Examples

TypeScript Client Singleton

// lib/deepgram.ts
import { createClient, DeepgramClient } from '@deepgram/sdk';

let client: DeepgramClient | null = null;

export function getDeepgramClient(): DeepgramClient {
  if (!client) {
    const apiKey = process.env.DEEPGRAM_API_KEY;
    if (!apiKey) {
      throw new Error('DEEPGRAM_API_KEY environment variable not set');
    }
    client = createClient(apiKey);
  }
  return client;
}

export function resetClient(): void {
  client = null;
}

Typed Transcription Response

// types/deepgram.ts
export interface TranscriptWord {
  word: string;
  start: number;
  end: number;
  confidence: number;
  punctuated_word?: string;
}

export interface TranscriptAlternative {
  transcript: string;
  confidence: number;
  words: TranscriptWord[];
}

export interface TranscriptChannel {
  alternatives: TranscriptAlternative[];
}

export interface TranscriptResult {
  results: {
    channels: TranscriptChannel[];
    utterances?: Array<{
      start: number;
      end: number;
      transcript: string;
      speaker: number;
    }>;
  };
  metadata: {
    request_id: string;
    model_uuid: string;
    model_info: Record<string, unknown>;
  };
}

Error Handling Wrapper

// lib/transcribe.ts
import { getDeepgramClient } from './deepgram';
import { TranscriptResult } from '../types/deepgram';

export class TranscriptionError extends Error {
  constructor(
    message: string,
    public readonly code: string,
    public readonly requestId?: string
  ) {
    super(message);
    this.name = 'TranscriptionError';
  }
}

export async function transcribeUrl(
  url: string,
  options: { model?: string; language?: string } = {}
): Promise<TranscriptResult> {
  const client = getDeepgramClient();

  try {
    const { result, error } = await client.listen.prerecorded.transcribeUrl(
      { url },
      {
        model: options.model || 'nova-2',
        language: options.language || 'en',
        smart_format: true,
        punctuate: true,
      }
    );

    if (error) {
      throw new TranscriptionError(
        error.message || 'Transcription failed',
        error.code || 'UNKNOWN_ERROR'
      );
    }

    return result as TranscriptResult;
  } catch (err) {
    if (err instanceof TranscriptionError) throw err;
    throw new TranscriptionError(
      err instanceof Error ? err.message : 'Unknown error',
      'NETWORK_ERROR'
    );
  }
}

Retry with Exponential Backoff

// lib/retry.ts
interface RetryOptions {
  maxRetries?: number;
  baseDelay?: number;
  maxDelay?: number;
}

export async function withRetry<T>(
  fn: () => Promise<T>,
  options: RetryOptions = {}
): Promise<T> {
  const { maxRetries = 3, baseDelay = 1000, maxDelay = 10000 } = options;

  let lastError: Error | undefined;

  for (let attempt = 0; attempt <= maxRetries; attempt++) {
    try {
      return await fn();
    } catch (error) {
      lastError = error instanceof Error ? error : new Error(String(error));

      // Don't retry on auth errors
      if (lastError.message.includes('401') ||
          lastError.message.includes('403')) {
        throw lastError;
      }

      if (attempt < maxRetries) {
        const delay = Math.min(baseDelay * Math.pow(2, attempt), maxDelay);
        await new Promise(resolve => setTimeout(resolve, delay));
      }
    }
  }

  throw lastError;
}

// Usage
const result = await withRetry(() => transcribeUrl(audioUrl));

Python Patterns

# lib/deepgram_client.py
from deepgram import DeepgramClient, PrerecordedOptions
from functools import lru_cache
import os

@lru_cache(maxsize=1)
def get_deepgram_client() -> DeepgramClient:
    """Get or create Deepgram client singleton."""
    api_key = os.environ.get('DEEPGRAM_API_KEY')
    if not api_key:
        raise ValueError('DEEPGRAM_API_KEY environment variable not set')
    return DeepgramClient(api_key)

def transcribe_url(url: str, model: str = 'nova-2') -> dict:
    """Transcribe audio from URL with error handling."""
    client = get_deepgram_client()

    options = PrerecordedOptions(
        model=model,
        smart_format=True,
        punctuate=True,
    )

    try:
        response = client.listen.rest.v("1").transcribe_url(
            {"url": url},
            options
        )
        return response.to_dict()
    except Exception as e:
        raise TranscriptionError(str(e)) from e

Resources

• Deepgram SDK Reference
• Deepgram TypeScript Types
• Error Handling Best Practices

Next Steps

Proceed to deepgram-core-workflow-a for speech-to-text workflow implementation.