service backend

api/fx/ingestor/internal/market/binance/connector.go

@@ -0,0 +1,139 @@
+package binance
+
+import (
+	"context"
+	"encoding/json"
+	"net"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/tech/sendico/fx/ingestor/internal/fmerrors"
+	"github.com/tech/sendico/fx/ingestor/internal/market/common"
+	mmodel "github.com/tech/sendico/fx/ingestor/internal/model"
+	"github.com/tech/sendico/pkg/mlogger"
+	"github.com/tech/sendico/pkg/model"
+	"go.uber.org/zap"
+)
+
+type binanceConnector struct {
+	id       mmodel.Driver
+	provider string
+	client   *http.Client
+	base     string
+	logger   mlogger.Logger
+}
+
+const defaultBinanceBaseURL = "https://api.binance.com"
+const (
+	defaultDialTimeoutSeconds           = 5 * time.Second
+	defaultDialKeepAliveSeconds         = 30 * time.Second
+	defaultTLSHandshakeTimeoutSeconds   = 5 * time.Second
+	defaultResponseHeaderTimeoutSeconds = 10 * time.Second
+	defaultRequestTimeoutSeconds        = 10 * time.Second
+)
+
+func NewConnector(logger mlogger.Logger, settings model.SettingsT) (mmodel.Connector, error) {
+	baseURL := defaultBinanceBaseURL
+	provider := strings.ToLower(mmodel.DriverBinance.String())
+	dialTimeout := defaultDialTimeoutSeconds
+	dialKeepAlive := defaultDialKeepAliveSeconds
+	tlsHandshakeTimeout := defaultTLSHandshakeTimeoutSeconds
+	responseHeaderTimeout := defaultResponseHeaderTimeoutSeconds
+	requestTimeout := defaultRequestTimeoutSeconds
+
+	if settings != nil {
+		if value, ok := settings["base_url"].(string); ok && strings.TrimSpace(value) != "" {
+			baseURL = strings.TrimSpace(value)
+		}
+		if value, ok := settings["provider"].(string); ok && strings.TrimSpace(value) != "" {
+			provider = strings.TrimSpace(value)
+		}
+		dialTimeout = common.DurationSetting(settings, "dial_timeout_seconds", dialTimeout)
+		dialKeepAlive = common.DurationSetting(settings, "dial_keep_alive_seconds", dialKeepAlive)
+		tlsHandshakeTimeout = common.DurationSetting(settings, "tls_handshake_timeout_seconds", tlsHandshakeTimeout)
+		responseHeaderTimeout = common.DurationSetting(settings, "response_header_timeout_seconds", responseHeaderTimeout)
+		requestTimeout = common.DurationSetting(settings, "request_timeout_seconds", requestTimeout)
+	}
+
+	parsed, err := url.Parse(baseURL)
+	if err != nil {
+		return nil, fmerrors.Wrap("binance: invalid base url", err)
+	}
+
+	transport := &http.Transport{
+		DialContext:           (&net.Dialer{Timeout: dialTimeout, KeepAlive: dialKeepAlive}).DialContext,
+		TLSHandshakeTimeout:   tlsHandshakeTimeout,
+		ResponseHeaderTimeout: responseHeaderTimeout,
+	}
+
+	connector := &binanceConnector{
+		id:       mmodel.DriverBinance,
+		provider: provider,
+		client: &http.Client{
+			Timeout:   requestTimeout,
+			Transport: transport,
+		},
+		base:   parsed.String(),
+		logger: logger.Named("binance"),
+	}
+
+	return connector, nil
+}
+
+func (c *binanceConnector) ID() mmodel.Driver {
+	return c.id
+}
+
+func (c *binanceConnector) FetchTicker(ctx context.Context, symbol string) (*mmodel.Ticker, error) {
+	if strings.TrimSpace(symbol) == "" {
+		return nil, fmerrors.New("binance: symbol is empty")
+	}
+
+	endpoint, err := url.Parse(c.base)
+	if err != nil {
+		return nil, fmerrors.Wrap("binance: parse base url", err)
+	}
+	endpoint.Path = "/api/v3/ticker/bookTicker"
+	query := endpoint.Query()
+	query.Set("symbol", strings.ToUpper(strings.TrimSpace(symbol)))
+	endpoint.RawQuery = query.Encode()
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, endpoint.String(), nil)
+	if err != nil {
+		return nil, fmerrors.Wrap("binance: build request", err)
+	}
+
+	resp, err := c.client.Do(req)
+	if err != nil {
+		c.logger.Warn("Binance request failed", zap.String("symbol", symbol), zap.Error(err))
+		return nil, fmerrors.Wrap("binance: request failed", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		c.logger.Warn("Binance returned non-OK status", zap.String("symbol", symbol), zap.Int("status", resp.StatusCode))
+		return nil, fmerrors.New("binance: unexpected status " + strconv.Itoa(resp.StatusCode))
+	}
+
+	var payload struct {
+		Symbol   string `json:"symbol"`
+		BidPrice string `json:"bidPrice"`
+		AskPrice string `json:"askPrice"`
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(&payload); err != nil {
+		c.logger.Warn("Binance decode failed", zap.String("symbol", symbol), zap.Error(err))
+		return nil, fmerrors.Wrap("binance: decode response", err)
+	}
+
+	return &mmodel.Ticker{
+		Symbol:    payload.Symbol,
+		BidPrice:  payload.BidPrice,
+		AskPrice:  payload.AskPrice,
+		Provider:  c.provider,
+		Timestamp: time.Now().UnixMilli(),
+	}, nil
+}