feat(analytics): vendor code for google analytics

Signed-off-by: Pawan <pawan@mayadata.io>

vendor/github.com/jpillora/go-ogle-analytics/client.go

@@ -0,0 +1,76 @@
+//go:generate go run generate/protocol.go
+
+package ga
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+)
+
+var trackingIDMatcher = regexp.MustCompile(`^UA-\d+-\d+$`)
+
+func NewClient(trackingID string) (*Client, error) {
+	if !trackingIDMatcher.MatchString(trackingID) {
+		return nil, fmt.Errorf("Invalid Tracking ID: %s", trackingID)
+	}
+	return &Client{
+		UseTLS:             true,
+		HttpClient:         http.DefaultClient,
+		protocolVersion:    "1",
+		protocolVersionSet: true,
+		trackingID:         trackingID,
+		clientID:           "go-ga",
+		clientIDSet:        true,
+	}, nil
+}
+
+type hitType interface {
+	addFields(url.Values) error
+}
+
+func (c *Client) Send(h hitType) error {
+
+	cpy := c.Copy()
+
+	v := url.Values{}
+
+	cpy.setType(h)
+
+	err := cpy.addFields(v)
+	if err != nil {
+		return err
+	}
+
+	err = h.addFields(v)
+	if err != nil {
+		return err
+	}
+
+	url := ""
+	if cpy.UseTLS {
+		url = "https://www.google-analytics.com/collect"
+	} else {
+		url = "http://ssl.google-analytics.com/collect"
+	}
+
+	str := v.Encode()
+	buf := bytes.NewBufferString(str)
+
+	resp, err := c.HttpClient.Post(url, "application/x-www-form-urlencoded", buf)
+	if err != nil {
+		return err
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode/100 != 2 {
+		return fmt.Errorf("Rejected by Google with code %d", resp.StatusCode)
+	}
+
+	// fmt.Printf("POST %s => %d\n", str, resp.StatusCode)
+
+	return nil
+}