finlight-client 2.0.1

Python client for the Finlight API

Finlight Client – Python Library

A Python client library for interacting with the Finlight News API. Finlight delivers real-time and historical financial news articles, enriched with sentiment analysis, company tagging, and market metadata. This library makes it easy to integrate Finlight into your Python applications.

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✨ Features

• Fetch structured news articles with date parsing and metadata.
• Filter by tickers, sources, languages, and date ranges.
• Stream real-time news updates via WebSocket with auto-reconnect.
• Webhook support with HMAC signature verification and replay attack protection.
• Advanced WebSocket features:
  • Exponential backoff reconnection strategy
  • Ping/pong keepalive mechanism
  • Proactive connection rotation (before AWS 2-hour limit)
  • Connection takeover for replacing existing connections
  • Rate limit and admin kick handling
• Strongly typed models using pydantic and dataclass.
• Lightweight and developer-friendly.

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📦 Installation

pip install finlight-client

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🚀 Quick Start

Fetch Articles via REST API

from finlight_client import FinlightApi, ApiConfig
from finlight_client.models import GetArticlesParams

def main():
    # Initialize the client
    config = ApiConfig(api_key="your_api_key")
    client = FinlightApi(config)

    # Create query parameters
    params = GetArticlesParams(
        query="Nvidia",
        language="en",
        from_="2024-01-01",
        to="2024-12-31",
        includeContent=True
    )

    # Fetch articles
    response = client.articles.fetch_articles(params=params)

    # Print results
    for article in response.articles:
        print(f"{article.publishDate} | {article.title}")

if __name__ == "__main__":
    main()

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Stream Real-Time Articles via WebSocket

import asyncio
from finlight_client import FinlightApi, ApiConfig
from finlight_client.models import GetArticlesWebSocketParams

def on_article(article):
    print("📨 Received:", article.title)

async def main():
    # Initialize the client
    config = ApiConfig(api_key="your_api_key")
    client = FinlightApi(config)

    # Create WebSocket parameters
    payload = GetArticlesWebSocketParams(
        query="Nvidia",
        sources=["www.reuters.com"],
        language="en",
        extended=True,
    )

    # Connect and listen for articles
    await client.websocket.connect(
        request_payload=payload,
        on_article=on_article
    )

if __name__ == "__main__":
    asyncio.run(main())

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⚙️ Configuration

ApiConfig

Core API configuration:

Parameter	Type	Description	Default
api_key	str	Your API key	Required
base_url	AnyHttpUrl	Base REST API URL	https://api.finlight.me
wss_url	AnyHttpUrl	WebSocket server URL	wss://wss.finlight.me
timeout	int	Request timeout in ms	5000
retry_count	int	Retry attempts on failures	3

FinlightApi WebSocket Options

Advanced WebSocket configuration (all optional):

Parameter	Type	Description	Default
websocket_ping_interval	int	Ping interval in seconds	25
websocket_pong_timeout	int	Pong timeout in seconds	60
websocket_base_reconnect_delay	float	Initial reconnect delay in seconds	0.5
websocket_max_reconnect_delay	float	Maximum reconnect delay in seconds	10.0
websocket_connection_lifetime	int	Connection lifetime in seconds	6900 (115m)
websocket_takeover	bool	Takeover existing connections	False
websocket_on_close	Callable	Callback for close events (code, reason)	None

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📚 API Overview

ArticleService.fetch_articles(params: GetArticlesParams) -> ArticleResponse

Fetch articles with flexible filtering:

• Supports advanced query strings with boolean operators
• Automatically parses ISO date strings into datetime
• Pagination with configurable page size (1-1000)
• Optional full content and entity tagging

SourcesService.get_sources() -> List[Source]

Retrieve available news sources:

• Returns list of sources with metadata
• Indicates content availability and default sources
• Useful for building source filters

WebSocketClient.connect(request_payload, on_article)

Subscribe to live article updates:

• Reconnects automatically with exponential backoff
• Handles rate limiting and admin actions gracefully
• Pings the server every 25s to keep the connection alive
• Proactively rotates connections before AWS 2-hour timeout
• Optional connection takeover mode

WebhookService.construct_event(raw_body, signature, endpoint_secret, timestamp?)

Securely receive webhook events:

• HMAC-SHA256 signature verification
• Replay attack protection (5-minute tolerance)
• Returns validated Article objects
• Raises WebhookVerificationError on invalid requests

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🧯 Error Handling

• Invalid date strings raise clear Python ValueErrors.
• REST and WebSocket exceptions are logged and managed.
• WebSocket includes reconnect, watchdog, and ping/pong mechanisms.

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📖 Additional Examples

Fetch Available Sources

from finlight_client import FinlightApi, ApiConfig

def main():
    config = ApiConfig(api_key="your_api_key")
    client = FinlightApi(config)

    sources = client.sources.get_sources()

    for source in sources:
        print(f"{source.domain} - Content: {source.isContentAvailable}")

if __name__ == "__main__":
    main()

Receive Webhook Events (Flask)

from flask import Flask, request
from finlight_client import WebhookService, WebhookVerificationError
import os

app = Flask(__name__)
webhook_service = WebhookService()

@app.route('/webhook', methods=['POST'])
def webhook():
    raw_body = request.get_data(as_text=True)
    signature = request.headers.get('X-Webhook-Signature')
    timestamp = request.headers.get('X-Webhook-Timestamp')

    try:
        article = webhook_service.construct_event(
            raw_body,
            signature,
            os.getenv('WEBHOOK_SECRET'),
            timestamp
        )
        print(f"📨 New article: {article.title}")
        return '', 200
    except WebhookVerificationError as e:
        print(f"❌ Invalid webhook: {e}")
        return '', 400

if __name__ == "__main__":
    app.run(port=3000)

Advanced WebSocket with Custom Configuration

import asyncio
from finlight_client import FinlightApi, ApiConfig
from finlight_client.models import GetArticlesWebSocketParams

def on_article(article):
    print(f"📨 {article.title}")

def on_close(code, reason):
    print(f"🔌 Connection closed: {code} - {reason}")

async def main():
    config = ApiConfig(api_key="your_api_key")

    # Advanced WebSocket configuration
    client = FinlightApi(
        config,
        websocket_ping_interval=30,  # Custom ping interval
        websocket_pong_timeout=90,   # Custom pong timeout
        websocket_takeover=True,     # Replace existing connections
        websocket_on_close=on_close  # Close event callback
    )

    payload = GetArticlesWebSocketParams(
        tickers=["NVDA", "AAPL"],
        language="en",
        extended=True,
        includeEntities=True
    )

    await client.websocket.connect(
        request_payload=payload,
        on_article=on_article
    )

if __name__ == "__main__":
    asyncio.run(main())

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🧰 Model Summary

GetArticlesParams (REST API)

Query parameters to filter articles:

Field	Type	Description
query	str	Search text with boolean operators
tickers	List[str]	Filter by ticker symbols (e.g., ["AAPL", "NVDA"])
sources	List[str]	Include specific sources
excludeSources	List[str]	Exclude specific sources
optInSources	List[str]	Include non-default sources
language	str	Language filter (e.g., "en", "de")
from_	str	Start date (YYYY-MM-DD or ISO)
to	str	End date (YYYY-MM-DD or ISO)
includeContent	bool	Include full article content (default: False)
includeEntities	bool	Include tagged companies (default: False)
excludeEmptyContent	bool	Only articles with content (default: False)
orderBy	str	Order by "publishDate" or "createdAt"
order	str	Sort order: "ASC" or "DESC"
page	int	Page number (starts at 1)
pageSize	int	Results per page (1-1000)

GetArticlesWebSocketParams (WebSocket)

Parameters for WebSocket subscriptions:

Field	Type	Description
query	str	Search text
tickers	List[str]	Filter by ticker symbols
sources	List[str]	Include specific sources
excludeSources	List[str]	Exclude specific sources
optInSources	List[str]	Include non-default sources
language	str	Language filter
extended	bool	Include full article details (default: False)
includeEntities	bool	Include tagged companies (default: False)
excludeEmptyContent	bool	Only articles with content (default: False)

Article

Article object fields:

Field	Type	Description
title	str	Article title
link	str	Article URL
publishDate	datetime	Publication date
source	str	Source domain
language	str	Article language code
summary	str	Article summary
content	str	Full article content (if available)
sentiment	str	Sentiment analysis result
confidence	float	Sentiment confidence score
images	List[str]	List of image URLs
companies	List[Company]	Tagged companies with metadata

Company

Tagged company information:

Field	Type	Description
companyId	int	Unique company identifier
name	str	Company name
ticker	str	Primary ticker symbol
confidence	float	Tagging confidence score
country	str	Company country
exchange	str	Primary exchange
sector	str	Business sector
industry	str	Industry classification
isin	str	ISIN code
openfigi	str	OpenFIGI identifier
primaryListing	Listing	Primary exchange listing
isins	List[str]	All ISIN codes
otherListings	List[Listing]	Other exchange listings

Source

News source metadata:

Field	Type	Description
domain	str	Source domain (e.g., "www.reuters.com")
isContentAvailable	bool	Whether full content is available
isDefaultSource	bool	Whether source is included by default

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🤝 Contributing

We welcome contributions and suggestions!

• Fork this repo
• Create a feature branch
• Submit a pull request with tests if applicable

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📄 License

MIT License – see LICENSE

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🔗 Resources

• Finlight API Documentation
• GitHub Repository
• PyPI Package