neoneo-go/pkg/rpc/client.go
Evgeniy Kulikov f000b76879 [FIX] Formatting and code-style (#118)
* [FIX] Formatting and code-style

- gofmt
- import resort
- prealloc slices
- simplify code

* fix vet
2019-01-25 12:20:35 +01:00

146 lines
3.2 KiB
Go

package rpc
import (
"bytes"
"context"
"encoding/json"
"fmt"
"net"
"net/http"
"net/url"
"time"
"github.com/CityOfZion/neo-go/pkg/wallet"
"github.com/pkg/errors"
)
var (
defaultDialTimeout = 4 * time.Second
defaultRequestTimeout = 4 * time.Second
defaultClientVersion = "2.0"
)
// Client represents the middleman for executing JSON RPC calls
// to remote NEO RPC nodes.
type Client struct {
// The underlying http client. It's never a good practice to use
// the http.DefaultClient, therefore we will role our own.
http.Client
endpoint *url.URL
ctx context.Context
version string
Wif *wallet.WIF
Balancer BalanceGetter
}
// ClientOptions defines options for the RPC client.
// All Values are optional. If any duration is not specified
// a default of 3 seconds will be used.
type ClientOptions struct {
Cert string
Key string
CACert string
DialTimeout time.Duration
RequestTimeout time.Duration
// Version is the version of the client that will be send
// along with the request body. If no version is specified
// the default version (currently 2.0) will be used.
Version string
}
// NewClient return a new Client ready to use.
func NewClient(ctx context.Context, endpoint string, opts ClientOptions) (*Client, error) {
url, err := url.Parse(endpoint)
if err != nil {
return nil, err
}
if opts.DialTimeout == 0 {
opts.DialTimeout = defaultDialTimeout
}
if opts.RequestTimeout == 0 {
opts.RequestTimeout = defaultRequestTimeout
}
if opts.Version == "" {
opts.Version = defaultClientVersion
}
transport := &http.Transport{
Dial: (&net.Dialer{
Timeout: opts.DialTimeout,
}).Dial,
}
// TODO(@antdm): Enable SSL.
if opts.Cert != "" && opts.Key != "" {
}
return &Client{
Client: http.Client{
Timeout: opts.RequestTimeout,
Transport: transport,
},
endpoint: url,
ctx: ctx,
version: opts.Version,
}, nil
}
// SetWIF decodes given WIF and adds some wallet
// data to client. Useful for RPC calls that require an open wallet.
func (c *Client) SetWIF(wif string) error {
decodedWif, err := wallet.WIFDecode(wif, 0x00)
if err != nil {
return errors.Wrap(err, "Failed to decode WIF; failed to add WIF to client ")
}
c.Wif = decodedWif
return nil
}
func (c *Client) SetBalancer(b BalanceGetter) {
c.Balancer = b
}
func (c *Client) performRequest(method string, p params, v interface{}) error {
var (
r = request{
JSONRPC: c.version,
Method: method,
Params: p.values,
ID: 1,
}
buf = new(bytes.Buffer)
)
if err := json.NewEncoder(buf).Encode(r); err != nil {
return err
}
req, err := http.NewRequest("POST", c.endpoint.String(), buf)
if err != nil {
return err
}
resp, err := c.Do(req)
if err != nil {
return err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("remote responded with a non 200 response: %d", resp.StatusCode)
}
return json.NewDecoder(resp.Body).Decode(v)
}
// Ping attempts to create a connection to the endpoint.
// and returns an error if there is one.
func (c *Client) Ping() error {
conn, err := net.DialTimeout("tcp", c.endpoint.Host, defaultDialTimeout)
if err != nil {
return err
}
_ = conn.Close()
return nil
}