add observer

sd/plugin/http.go

@@ -0,0 +1,213 @@
+package sd
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/go-gost/core/logger"
+	"github.com/go-gost/core/sd"
+	"github.com/go-gost/x/internal/plugin"
+)
+
+type sdService struct {
+	ID      string `json:"id"`
+	Name    string `json:"name"`
+	Node    string `json:"node"`
+	Network string `json:"network"`
+	Address string `json:"address"`
+}
+
+type httpGetResponse struct {
+	Services []*sdService `json:"services"`
+}
+
+type httpPlugin struct {
+	url    string
+	client *http.Client
+	header http.Header
+	log    logger.Logger
+}
+
+// NewHTTPPlugin creates an SD plugin based on HTTP.
+func NewHTTPPlugin(name string, url string, opts ...plugin.Option) sd.SD {
+	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": "sd",
+			"sd":   name,
+		}),
+	}
+}
+
+func (p *httpPlugin) Register(ctx context.Context, service *sd.Service, opts ...sd.Option) error {
+	if p.client == nil || service == nil {
+		return nil
+	}
+
+	v, err := json.Marshal(sdService{
+		ID:      service.ID,
+		Name:    service.Name,
+		Node:    service.Node,
+		Network: service.Network,
+		Address: service.Address,
+	})
+	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
+}
+
+func (p *httpPlugin) Deregister(ctx context.Context, service *sd.Service) error {
+	if p.client == nil || service == nil {
+		return nil
+	}
+
+	v, err := json.Marshal(sdService{
+		ID:      service.ID,
+		Name:    service.Name,
+		Node:    service.Node,
+		Network: service.Network,
+		Address: service.Address,
+	})
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodDelete, 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
+}
+
+func (p *httpPlugin) Renew(ctx context.Context, service *sd.Service) error {
+	if p.client == nil {
+		return nil
+	}
+
+	v, err := json.Marshal(sdService{
+		ID:      service.ID,
+		Name:    service.Name,
+		Node:    service.Node,
+		Network: service.Network,
+		Address: service.Address,
+	})
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPut, 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
+}
+
+func (p *httpPlugin) Get(ctx context.Context, name string) (services []*sd.Service, err error) {
+	if p.client == nil {
+		return
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, p.url, nil)
+	if err != nil {
+		return
+	}
+
+	if p.header != nil {
+		req.Header = p.header.Clone()
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	q := req.URL.Query()
+	q.Set("name", name)
+	req.URL.RawQuery = q.Encode()
+
+	resp, err := p.client.Do(req)
+	if err != nil {
+		return
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf(resp.Status)
+	}
+
+	res := &httpGetResponse{}
+	if err := json.NewDecoder(resp.Body).Decode(&res); err != nil {
+		return nil, err
+	}
+
+	for _, v := range res.Services {
+		if v == nil {
+			continue
+		}
+		services = append(services, &sd.Service{
+			ID:      v.ID,
+			Name:    v.Name,
+			Node:    v.Node,
+			Network: v.Network,
+			Address: v.Address,
+		})
+	}
+	return
+}