example/README.md

llm_chatgpt Examples #

Prerequisites #

1. OpenAI API Key: Get your API key from platform.openai.com
2. Internet Connection: Required to connect to OpenAI API

CLI Example #

A simple command-line chat interface:

cd packages/llm_chatgpt
export OPENAI_API_KEY=your-api-key
dart run example/cli_example.dart

With custom model:

OPENAI_API_KEY=your-key dart run example/cli_example.dart gpt-4o

Or pass API key as argument:

dart run example/cli_example.dart gpt-4o-mini your-api-key

Using in Your Own Code #

Basic Usage #

import 'package:llm_chatgpt/llm_chatgpt.dart';

Future<void> main() async {
  final repo = ChatGPTChatRepository(apiKey: 'your-api-key');
  
  final stream = repo.streamChat('gpt-4o-mini', messages: [
    LLMMessage(role: LLMRole.system, content: 'You are helpful.'),
    LLMMessage(role: LLMRole.user, content: 'Hello!'),
  ]);
  
  await for (final chunk in stream) {
    print(chunk.message?.content ?? '');
  }
}

With Builder Pattern #

final repo = ChatGPTChatRepository.builder()
  .apiKey('your-api-key')
  .baseUrl('https://api.openai.com') // Default
  .retryConfig(RetryConfig(maxAttempts: 3))
  .timeoutConfig(TimeoutConfig(readTimeout: Duration(minutes: 5)))
  .build();

Azure OpenAI #

final repo = ChatGPTChatRepository.builder()
  .apiKey('your-azure-api-key')
  .baseUrl('https://your-resource.openai.azure.com')
  .build();

Non-Streaming Response #

final response = await repo.chatResponse('gpt-4o-mini', messages: [
  LLMMessage(role: LLMRole.user, content: 'What is 2+2?'),
]);

print(response.content);
print('Tokens: ${response.evalCount}');

Tool Calling #

class CalculatorTool extends LLMTool {
  @override
  String get name => 'calculator';
  
  @override
  String get description => 'Performs arithmetic calculations';
  
  @override
  List<LLMToolParam> get parameters => [
    LLMToolParam(
      name: 'expression',
      type: 'string',
      description: 'The math expression to evaluate',
      isRequired: true,
    ),
  ];
  
  @override
  Future<String> execute(Map<String, dynamic> args, {dynamic extra}) async {
    final expr = args['expression'] as String;
    // Evaluate expression...
    return result.toString();
  }
}

final stream = repo.streamChat(
  'gpt-4o-mini',
  messages: messages,
  tools: [CalculatorTool()],
);

Embeddings #

final embeddings = await repo.embed(
  'text-embedding-3-small',
  ['Hello, world!', 'How are you?'],
);

for (final embedding in embeddings) {
  print('Embedding: ${embedding.embedding.length} dimensions');
}

Configuration #

Environment Variables #

Set your API key via environment variable:

export OPENAI_API_KEY=your-api-key
dart run example/cli_example.dart

Or use CHATGPT_ACCESS_TOKEN:

export CHATGPT_ACCESS_TOKEN=your-token
dart run example/cli_example.dart

Custom Base URL #

For Azure OpenAI or custom endpoints:

final repo = ChatGPTChatRepository.builder()
  .apiKey('your-key')
  .baseUrl('https://your-resource.openai.azure.com')
  .build();

Available Models #

Chat Models #

• gpt-4o - Latest GPT-4 optimized model
• gpt-4o-mini - Faster, cheaper GPT-4 variant
• gpt-4-turbo - GPT-4 Turbo
• gpt-3.5-turbo - GPT-3.5 Turbo

Embedding Models #

• text-embedding-3-small - Small, fast embeddings
• text-embedding-3-large - Large, high-quality embeddings
• text-embedding-ada-002 - Legacy embedding model

Troubleshooting #

Invalid API key #

• Verify your API key at platform.openai.com
• Check for typos or extra spaces
• Ensure the key has the correct permissions

Rate limit errors #

• Implement retry logic with exponential backoff (built-in via RetryConfig)
• Use a model with higher rate limits
• Consider upgrading your OpenAI plan

Network errors #

• Check your internet connection
• Verify firewall/proxy settings
• Ensure OpenAI API is accessible from your network

Azure OpenAI #

• Use the correct base URL format: https://<resource>.openai.azure.com
• Ensure API version is compatible
• Check Azure resource permissions