feature: added nsq as broker for events (#6740)

vendor/github.com/nsqio/go-nsq/api_request.go

@@ -0,0 +1,91 @@
+package nsq
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"time"
+)
+
+type deadlinedConn struct {
+	Timeout time.Duration
+	net.Conn
+}
+
+func (c *deadlinedConn) Read(b []byte) (n int, err error) {
+	c.Conn.SetReadDeadline(time.Now().Add(c.Timeout))
+	return c.Conn.Read(b)
+}
+
+func (c *deadlinedConn) Write(b []byte) (n int, err error) {
+	c.Conn.SetWriteDeadline(time.Now().Add(c.Timeout))
+	return c.Conn.Write(b)
+}
+
+func newDeadlineTransport(timeout time.Duration) *http.Transport {
+	transport := &http.Transport{
+		DisableKeepAlives: true,
+		Dial: func(netw, addr string) (net.Conn, error) {
+			c, err := net.DialTimeout(netw, addr, timeout)
+			if err != nil {
+				return nil, err
+			}
+			return &deadlinedConn{timeout, c}, nil
+		},
+	}
+	return transport
+}
+
+type wrappedResp struct {
+	Status     string      `json:"status_txt"`
+	StatusCode int         `json:"status_code"`
+	Data       interface{} `json:"data"`
+}
+
+// stores the result in the value pointed to by ret(must be a pointer)
+func apiRequestNegotiateV1(method string, endpoint string, body io.Reader, ret interface{}) error {
+	httpclient := &http.Client{Transport: newDeadlineTransport(2 * time.Second)}
+	req, err := http.NewRequest(method, endpoint, body)
+	if err != nil {
+		return err
+	}
+
+	req.Header.Add("Accept", "application/vnd.nsq; version=1.0")
+
+	resp, err := httpclient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	respBody, err := ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != 200 {
+		return fmt.Errorf("got response %s %q", resp.Status, respBody)
+	}
+
+	if len(respBody) == 0 {
+		respBody = []byte("{}")
+	}
+
+	if resp.Header.Get("X-NSQ-Content-Type") == "nsq; version=1.0" {
+		return json.Unmarshal(respBody, ret)
+	}
+
+	wResp := &wrappedResp{
+		Data: ret,
+	}
+
+	if err = json.Unmarshal(respBody, wResp); err != nil {
+		return err
+	}
+
+	// wResp.StatusCode here is equal to resp.StatusCode, so ignore it
+	return nil
+}