bbgo_origin/pkg/exchange/bitget/bitgetapi/client.go

package bitgetapi

import (
	"bytes"
	"context"
	"crypto/hmac"
	"crypto/sha256"
	"encoding/base64"
	"encoding/json"
	"net/http"
	"net/url"
	"strings"
	"time"

	"github.com/pkg/errors"

	"github.com/c9s/bbgo/pkg/util"
)

const defaultHTTPTimeout = time.Second * 15
const RestBaseURL = "https://api.bitget.com"
const PublicWebSocketURL = "wss://ws.bitget.com/spot/v1/stream"
const PrivateWebSocketURL = "wss://ws.bitget.com/spot/v1/stream"

type RestClient struct {
	BaseURL *url.URL
	client  *http.Client

	Key, Secret, Passphrase string
}

func NewClient() *RestClient {
	u, err := url.Parse(RestBaseURL)
	if err != nil {
		panic(err)
	}

	return &RestClient{
		BaseURL: u,
		client: &http.Client{
			Timeout: defaultHTTPTimeout,
		},
	}
}

func (c *RestClient) Auth(key, secret, passphrase string) {
	c.Key = key
	// pragma: allowlist nextline secret
	c.Secret = secret
	c.Passphrase = passphrase
}

// NewRequest create new API request. Relative url can be provided in refURL.
func (c *RestClient) newRequest(ctx context.Context, method, refURL string, params url.Values, body []byte) (*http.Request, error) {
	rel, err := url.Parse(refURL)
	if err != nil {
		return nil, err
	}

	if params != nil {
		rel.RawQuery = params.Encode()
	}

	pathURL := c.BaseURL.ResolveReference(rel)
	return http.NewRequestWithContext(ctx, method, pathURL.String(), bytes.NewReader(body))
}

// sendRequest sends the request to the API server and handle the response
func (c *RestClient) sendRequest(req *http.Request) (*util.Response, error) {
	resp, err := c.client.Do(req)
	if err != nil {
		return nil, err
	}

	// newResponse reads the response body and return a new Response object
	response, err := util.NewResponse(resp)
	if err != nil {
		return response, err
	}

	// Check error, if there is an error, return the ErrorResponse struct type
	if response.IsError() {
		return response, errors.New(string(response.Body))
	}

	return response, nil
}

// newAuthenticatedRequest creates new http request for authenticated routes.
func (c *RestClient) NewAuthenticatedRequest(ctx context.Context, method, refURL string, params url.Values, payload interface{}) (*http.Request, error) {
	if len(c.Key) == 0 {
		return nil, errors.New("empty api key")
	}

	if len(c.Secret) == 0 {
		return nil, errors.New("empty api secret")
	}

	rel, err := url.Parse(refURL)
	if err != nil {
		return nil, err
	}

	if params != nil {
		rel.RawQuery = params.Encode()
	}

	pathURL := c.BaseURL.ResolveReference(rel)
	path := pathURL.Path
	if rel.RawQuery != "" {
		path += "?" + rel.RawQuery
	}

	// set location to UTC so that it outputs "2020-12-08T09:08:57.715Z"
	t := time.Now().In(time.UTC)
	timestamp := t.Format("2006-01-02T15:04:05.999Z07:00")

	var body []byte

	if payload != nil {
		switch v := payload.(type) {
		case string:
			body = []byte(v)

		case []byte:
			body = v

		default:
			body, err = json.Marshal(v)
			if err != nil {
				return nil, err
			}
		}
	}

	signKey := timestamp + strings.ToUpper(method) + path + string(body)
	signature := Sign(signKey, c.Secret)

	req, err := http.NewRequestWithContext(ctx, method, pathURL.String(), bytes.NewReader(body))
	if err != nil {
		return nil, err
	}

	req.Header.Add("Content-Type", "application/json")
	req.Header.Add("Accept", "application/json")
	req.Header.Add("ACCESS-KEY", c.Key)
	req.Header.Add("ACCESS-SIGN", signature)
	req.Header.Add("ACCESS-TIMESTAMP", timestamp)
	req.Header.Add("ACCESS-PASSPHRASE", c.Passphrase)
	return req, nil
}

func Sign(payload string, secret string) string {
	var sig = hmac.New(sha256.New, []byte(secret))
	_, err := sig.Write([]byte(payload))
	if err != nil {
		return ""
	}

	return base64.StdEncoding.EncodeToString(sig.Sum(nil))
	// return hex.EncodeToString(sig.Sum(nil))
}