added

internal/finnhub/client.go

@@ -0,0 +1,75 @@
+package finnhub
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+const baseURL = "https://finnhub.io/api/v1"
+
+type Client struct {
+	apiKey string
+	http   *http.Client
+}
+
+type NewsItem struct {
+	ID       int    `json:"id"`
+	Category string `json:"category"`
+	Datetime int64  `json:"datetime"`
+	Headline string `json:"headline"`
+	Related  string `json:"related"`
+	Source   string `json:"source"`
+	URL      string `json:"url"`
+	Summary  string `json:"summary"`
+}
+
+func New(apiKey string) *Client {
+	return &Client{
+		apiKey: apiKey,
+		http:   &http.Client{Timeout: 10 * time.Second},
+	}
+}
+
+func (c *Client) CompanyNews(symbol, from, to string) ([]NewsItem, error) {
+	url := fmt.Sprintf("%s/company-news?symbol=%s&from=%s&to=%s&token=%s",
+		baseURL, symbol, from, to, c.apiKey)
+	return c.fetchNews(url)
+}
+
+func (c *Client) MarketNews() ([]NewsItem, error) {
+	url := fmt.Sprintf("%s/news?category=general&token=%s", baseURL, c.apiKey)
+	return c.fetchNews(url)
+}
+
+func (c *Client) Ping() error {
+	url := fmt.Sprintf("%s/news?category=general&minId=999999999&token=%s", baseURL, c.apiKey)
+	resp, err := c.http.Get(url)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode == 401 || resp.StatusCode == 403 {
+		return fmt.Errorf("invalid API key (HTTP %d)", resp.StatusCode)
+	}
+	return nil
+}
+
+func (c *Client) fetchNews(url string) ([]NewsItem, error) {
+	resp, err := c.http.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("finnhub: HTTP %d", resp.StatusCode)
+	}
+
+	var items []NewsItem
+	if err := json.NewDecoder(resp.Body).Decode(&items); err != nil {
+		return nil, err
+	}
+	return items, nil
+}