add observer

observer/plugin/http.go

@@ -0,0 +1,134 @@
+package observer
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/go-gost/core/logger"
+	"github.com/go-gost/core/observer"
+	"github.com/go-gost/x/internal/plugin"
+	"github.com/go-gost/x/service"
+	"github.com/go-gost/x/stats"
+)
+
+type observeRequest struct {
+	Events []event `json:"events"`
+}
+
+type event struct {
+	Kind    string             `json:"kind"`
+	Service string             `json:"service"`
+	Client  string             `json:"client,omitempty"`
+	Type    observer.EventType `json:"type"`
+	Stats   *statsEvent        `json:"stats,omitempty"`
+	Status  *statusEvent       `json:"status,omitempty"`
+}
+
+type statsEvent struct {
+	TotalConns   uint64 `json:"totalConns"`
+	CurrentConns uint64 `json:"currentConns"`
+	InputBytes   uint64 `json:"inputBytes"`
+	OutputBytes  uint64 `json:"outputBytes"`
+	TotalErrs    uint64 `json:"totalErrs"`
+}
+
+type statusEvent struct {
+	State string `json:"state"`
+	Msg   string `json:"msg"`
+}
+
+type observeResponse struct {
+	OK bool `json:"ok"`
+}
+
+type httpPlugin struct {
+	url    string
+	client *http.Client
+	header http.Header
+	log    logger.Logger
+}
+
+// NewHTTPPlugin creates an Observer plugin based on HTTP.
+func NewHTTPPlugin(name string, url string, opts ...plugin.Option) observer.Observer {
+	var options plugin.Options
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	return &httpPlugin{
+		url:    url,
+		client: plugin.NewHTTPClient(&options),
+		header: options.Header,
+		log: logger.Default().WithFields(map[string]any{
+			"kind":     "observer",
+			"observer": name,
+		}),
+	}
+}
+
+func (p *httpPlugin) Observe(ctx context.Context, events []observer.Event, opts ...observer.Option) error {
+	if p.client == nil || len(events) == 0 {
+		return nil
+	}
+
+	var r observeRequest
+
+	for _, e := range events {
+		switch e.Type() {
+		case observer.EventStatus:
+			ev := e.(service.ServiceEvent)
+			r.Events = append(r.Events, event{
+				Kind:    ev.Kind,
+				Service: ev.Service,
+				Type:    ev.Type(),
+				Status: &statusEvent{
+					State: string(ev.State),
+					Msg:   ev.Msg,
+				},
+			})
+		case observer.EventStats:
+			ev := e.(stats.StatsEvent)
+			r.Events = append(r.Events, event{
+				Kind:    ev.Kind,
+				Service: ev.Service,
+				Client:  ev.Client,
+				Type:    ev.Type(),
+				Stats: &statsEvent{
+					TotalConns:   ev.TotalConns,
+					CurrentConns: ev.CurrentConns,
+					InputBytes:   ev.InputBytes,
+					OutputBytes:  ev.OutputBytes,
+					TotalErrs:    ev.TotalErrs,
+				},
+			})
+		}
+	}
+	v, err := json.Marshal(r)
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, p.url, bytes.NewReader(v))
+	if err != nil {
+		return err
+	}
+
+	if p.header != nil {
+		req.Header = p.header.Clone()
+	}
+	req.Header.Set("Content-Type", "application/json")
+	resp, err := p.client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf(resp.Status)
+	}
+
+	return nil
+}