feat(sdk-go): initial version

sdk-go/client/client.go

@@ -0,0 +1,192 @@
+package client
+
+import (
+	"bytes"
+	"crypto/rand"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/tjfoc/gmsm/sm2"
+
+	"go.fusiongalaxy.cn/bdware/bdcontract-client/sm2util"
+)
+
+type HttpCOptions struct {
+	MaxRetries int
+}
+
+type Client struct {
+	baseUrl  string
+	priv     *sm2.PrivateKey
+	pub      *sm2.PublicKey
+	pubHex   string
+	httpc    *http.Client
+	maxRetry int
+}
+
+func NewClient(
+	baseUrl string,
+	priv *sm2.PrivateKey,
+	pub *sm2.PublicKey,
+	opt HttpCOptions,
+) (*Client, error) {
+	pubHex, err := sm2util.CheckSm2KeyPair(priv, pub)
+	if err != nil {
+		return nil, err
+	}
+
+	if opt.MaxRetries == 0 {
+		opt.MaxRetries = 3
+	}
+
+	return &Client{
+		baseUrl:  baseUrl,
+		pub:      pub,
+		pubHex:   pubHex,
+		priv:     priv,
+		httpc:    &http.Client{Timeout: 10 * time.Second},
+		maxRetry: opt.MaxRetries,
+	}, nil
+}
+
+func (c *Client) RequestWithSignature(
+	path string,
+	method string,
+	body map[string]interface{},
+	priv *sm2.PrivateKey,
+	pub *sm2.PublicKey,
+) (statusCode int, respBody io.ReadCloser, err error) {
+	var pubHex string
+	if priv != nil {
+		var err error
+		pubHex, err = sm2util.CheckSm2KeyPair(priv, pub)
+		if err != nil {
+			return 0, nil, err
+		}
+	} else {
+		priv = c.priv
+		pubHex = c.pubHex
+	}
+
+	rawUrl := c.baseUrl + path
+	u := fmt.Sprintf("%s%spubKey=%s",
+		rawUrl,
+		func() string {
+			if strings.Contains(path, "?") {
+				return "&"
+			}
+			return "?"
+		}(),
+		pubHex,
+	)
+
+	switch strings.ToUpper(method) {
+	case "POST":
+		body["sign"] = c.Sign(u[strings.Index(u, "?")+1:], priv)
+
+		bodyJson, err := json.Marshal(body)
+		if err != nil {
+			return 0, nil, err
+		}
+
+		resp, err := c.httpc.Post(rawUrl, "application/json", bytes.NewBuffer(bodyJson))
+		if err != nil {
+			return 0, nil, err
+		}
+		respBody = resp.Body
+	}
+
+	return statusCode, respBody, nil
+}
+
+func (c *Client) Sign(data string, priv *sm2.PrivateKey) string {
+	if priv == nil {
+		priv = c.priv
+	}
+	sig, err := priv.Sign(rand.Reader, []byte(data), nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return hex.EncodeToString(sig)
+}
+
+func genUrlParamsFromObject(obj map[string]interface{}) string {
+	params := make([]string, 0)
+	for key, value := range obj {
+		params = append(params, fmt.Sprintf("%s=%v", key, value))
+	}
+	return strings.Join(params, "&")
+}
+
+func retry[T any](fn func() (int, T, error)) (int, T, error) {
+	var lastErr error
+	for attempt := 0; attempt < 3; attempt++ {
+		resp, statusCode, err := fn()
+		if err == nil {
+			return resp, statusCode, nil
+		}
+		lastErr = err
+		time.Sleep(100 * time.Millisecond * time.Duration(attempt+1))
+	}
+	var zero T
+	return 0, zero, lastErr
+}
+
+func (c *Client) Ping() (statusCode int, resp *PingResponse, err error) {
+	return retry(func() (statusCode int, resp *PingResponse, err error) {
+		statusCode, respBody, err := c.RequestWithSignature(
+			"/SCManager?action=ping",
+			"GET",
+			nil,
+			nil,
+			nil,
+		)
+		if err != nil {
+			return 0, nil, err
+		}
+
+		defer respBody.Close()
+		decoder := json.NewDecoder(respBody)
+		if err := decoder.Decode(&resp); err != nil {
+			return 0, nil, err
+		}
+
+		return statusCode, resp, nil
+	})
+}
+
+func (c *Client) StartContract(code string) (statusCode int, resp string, err error) {
+	params := url.Values{
+		"action": {"startContract"},
+		"script": {code},
+	}
+	path := fmt.Sprintf("/SCManager?%s", params.Encode())
+	return retry(func() (int, string, error) {
+		statusCode, respBody, err := c.RequestWithSignature(
+			path,
+			"GET",
+			nil,
+			nil,
+			nil,
+		)
+		if err != nil {
+			return 0, "", err
+		}
+
+		var resp string
+		defer respBody.Close()
+		buf := new(strings.Builder)
+		if _, err := io.Copy(buf, respBody); err != nil {
+			return 0, "", err
+		}
+
+		return statusCode, resp, nil
+	})
+}