14 "github.com/bytom/vapor/errors"
15 "github.com/bytom/vapor/net/http/httperror"
18 // Bytom-specific header fields
20 HeaderBlockchainID = "Blockchain-ID"
21 HeaderCoreID = "Bytom-Core-ID"
22 HeaderTimeout = "RPC-Timeout"
25 // ErrWrongNetwork is returned when a peer's blockchain ID differs from
26 // the RPC client's blockchain ID.
27 var ErrWrongNetwork = errors.New("connected to a peer on a different network")
29 // A Client is a Bytom RPC client. It performs RPCs over HTTP using JSON
30 // request and responses. A Client must be configured with a secret token
31 // to authenticate with other Cores on the network.
40 // If set, Client is used for outgoing requests.
41 // TODO(kr): make this required (crash on nil)
45 func (c Client) userAgent() string {
46 return fmt.Sprintf("Bytom; process=%s; buildtag=%s; blockchainID=%s",
47 c.Username, c.BuildTag, c.BlockchainID)
50 // ErrStatusCode is an error returned when an rpc fails with a non-200
52 type ErrStatusCode struct {
55 ErrorData *httperror.Response
58 func (e ErrStatusCode) Error() string {
59 return fmt.Sprintf("Request to `%s` responded with %d %s",
60 e.URL, e.StatusCode, http.StatusText(e.StatusCode))
63 // Call calls a remote procedure on another node, specified by the path.
64 func (c *Client) Call(ctx context.Context, path string, request, response interface{}) error {
65 r, err := c.CallRaw(ctx, path, request)
71 decoder := json.NewDecoder(r)
73 err = errors.Wrap(decoder.Decode(response))
78 // CallRaw calls a remote procedure on another node, specified by the path. It
79 // returns a io.ReadCloser of the raw response body.
80 func (c *Client) CallRaw(ctx context.Context, path string, request interface{}) (io.ReadCloser, error) {
81 u, err := url.Parse(c.BaseURL)
83 return nil, errors.Wrap(err)
87 var bodyReader io.Reader
89 var jsonBody bytes.Buffer
90 if err := json.NewEncoder(&jsonBody).Encode(request); err != nil {
91 return nil, errors.Wrap(err)
93 bodyReader = &jsonBody
96 req, err := http.NewRequest("POST", u.String(), bodyReader)
98 return nil, errors.Wrap(err)
101 if c.AccessToken != "" {
102 var username, password string
103 toks := strings.SplitN(c.AccessToken, ":", 2)
110 req.SetBasicAuth(username, password)
113 // Propagate our request ID so that we can trace a request across nodes.
114 req.Header.Set("Content-Type", "application/json")
115 req.Header.Set("User-Agent", c.userAgent())
116 req.Header.Set(HeaderBlockchainID, c.BlockchainID)
117 req.Header.Set(HeaderCoreID, c.CoreID)
119 // Propagate our deadline if we have one.
120 deadline, ok := ctx.Deadline()
122 req.Header.Set(HeaderTimeout, deadline.Sub(time.Now()).String())
127 client = http.DefaultClient
129 resp, err := client.Do(req.WithContext(ctx))
130 if err != nil && ctx.Err() != nil { // check if it timed out
131 return nil, errors.Wrap(ctx.Err())
132 } else if err != nil {
133 return nil, errors.Wrap(err)
136 if id := resp.Header.Get(HeaderBlockchainID); c.BlockchainID != "" && id != "" && c.BlockchainID != id {
138 return nil, errors.Wrap(ErrWrongNetwork)
141 if resp.StatusCode < 200 || resp.StatusCode >= 300 {
142 defer resp.Body.Close()
144 resErr := ErrStatusCode{
145 URL: cleanedURLString(u),
146 StatusCode: resp.StatusCode,
149 // Attach formatted error message, if available
150 var errData httperror.Response
151 err := json.NewDecoder(resp.Body).Decode(&errData)
152 if err == nil && errData.ChainCode != "" {
153 resErr.ErrorData = &errData
159 return resp.Body, nil
162 func cleanedURLString(u *url.URL) string {