Files
platforms/backend/iot-client/internal/service/service.go

219 lines
6.8 KiB
Go

// Package service 提供管理系统/App 与 IoT 设备链路之间的稳定上下行 HTTP 边界。
package service
import (
"bytes"
"context"
"crypto/subtle"
"encoding/json"
"fmt"
"io"
"net/http"
"strings"
"sync"
"time"
"git.apinb.com/heqiapp/platforms/backend/iot-client/internal/config"
)
type Service struct {
cfg config.Config
client *http.Client
mu sync.RWMutex
byIdentity map[string]Command
byIdempotency map[string]string
http *http.Server
}
type Command struct {
Identity string `json:"identity"`
IdempotencyKey string `json:"idempotency_key"`
DeviceID string `json:"device_id"`
Action string `json:"action"`
ExpiresAt time.Time `json:"expires_at"`
KeyID byte `json:"key_id"`
DeviceKind byte `json:"device_kind"`
DeviceType byte `json:"device_type"`
DeviceModel [3]byte `json:"device_model"`
Controller byte `json:"controller"`
Loop byte `json:"loop"`
Component byte `json:"component"`
Status string `json:"status"`
PacketNumber uint16 `json:"packet_number,omitempty"`
ErrorCode string `json:"error_code,omitempty"`
CreatedAt time.Time `json:"created_at"`
UpdatedAt time.Time `json:"updated_at"`
}
type deviceEnvelope struct {
Type, Topic, DeviceID, ReceivedAt, PayloadHex string
Frame json.RawMessage `json:"frame,omitempty"`
}
func New(cfg config.Config) *Service {
return &Service{cfg: cfg, client: &http.Client{Timeout: 12 * time.Second}, byIdentity: map[string]Command{}, byIdempotency: map[string]string{}}
}
func (s *Service) Run(ctx context.Context) error {
mux := http.NewServeMux()
mux.HandleFunc("/health", func(w http.ResponseWriter, _ *http.Request) { w.WriteHeader(http.StatusNoContent) })
mux.HandleFunc("/v1/device-commands", s.commands)
mux.HandleFunc("/v1/device-commands/", s.commandStatus)
mux.HandleFunc("/internal/v1/device-messages", s.deviceMessage)
s.http = &http.Server{Addr: s.cfg.HTTP.Address, Handler: mux, ReadHeaderTimeout: 5 * time.Second}
go func() {
<-ctx.Done()
shutdown, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()
_ = s.http.Shutdown(shutdown)
}()
err := s.http.ListenAndServe()
if err == http.ErrServerClosed {
return nil
}
return err
}
func (s *Service) commands(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodPost {
http.Error(w, "method not allowed", 405)
return
}
if !s.authorized(r) {
http.Error(w, "unauthorized", 401)
return
}
var cmd Command
if err := json.NewDecoder(io.LimitReader(r.Body, 64<<10)).Decode(&cmd); err != nil {
http.Error(w, "invalid json", 400)
return
}
if cmd.Identity == "" || cmd.IdempotencyKey == "" || cmd.DeviceID == "" || (cmd.Action != "open_valve" && cmd.Action != "close_valve") {
http.Error(w, "invalid command", 422)
return
}
if cmd.ExpiresAt.IsZero() {
cmd.ExpiresAt = time.Now().Add(30 * time.Second)
}
if time.Now().After(cmd.ExpiresAt) {
http.Error(w, "command expired", 422)
return
}
s.mu.Lock()
if existingID, ok := s.byIdempotency[cmd.IdempotencyKey]; ok {
existing := s.byIdentity[existingID]
s.mu.Unlock()
writeJSON(w, http.StatusOK, existing)
return
}
cmd.Status = "accepted"
cmd.CreatedAt = time.Now().UTC()
cmd.UpdatedAt = cmd.CreatedAt
s.byIdentity[cmd.Identity] = cmd
s.byIdempotency[cmd.IdempotencyKey] = cmd.Identity
s.mu.Unlock()
status, packet, err := s.dispatch(r.Context(), cmd)
s.mu.Lock()
current := s.byIdentity[cmd.Identity]
current.UpdatedAt = time.Now().UTC()
if err != nil {
current.Status = "dispatch_failed"
current.ErrorCode = "IOT_DISPATCH_FAILED"
} else {
current.Status = status
current.PacketNumber = packet
}
s.byIdentity[cmd.Identity] = current
s.mu.Unlock()
if err != nil {
writeJSON(w, http.StatusBadGateway, current)
return
}
writeJSON(w, http.StatusAccepted, current)
}
func (s *Service) commandStatus(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodGet {
http.Error(w, "method not allowed", 405)
return
}
if !s.authorized(r) {
http.Error(w, "unauthorized", 401)
return
}
identity := strings.TrimPrefix(r.URL.Path, "/v1/device-commands/")
s.mu.RLock()
cmd, ok := s.byIdentity[identity]
s.mu.RUnlock()
if !ok {
http.Error(w, "not found", 404)
return
}
writeJSON(w, 200, cmd)
}
func (s *Service) deviceMessage(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodPost || !s.authorized(r) {
http.Error(w, "unauthorized", 401)
return
}
data, err := io.ReadAll(io.LimitReader(r.Body, 1<<20))
if err != nil {
http.Error(w, "invalid body", 400)
return
}
var envelope deviceEnvelope
if json.Unmarshal(data, &envelope) != nil || envelope.ReceivedAt == "" {
http.Error(w, "invalid envelope", 422)
return
}
request, err := http.NewRequestWithContext(r.Context(), http.MethodPost, s.cfg.Upstream.PlatformAPIURL+"/heqi/internal/v1/iot/device-messages", bytes.NewReader(data))
if err != nil {
http.Error(w, "upstream request failed", 502)
return
}
request.Header.Set("Content-Type", "application/json")
request.Header.Set("X-Heqi-Iot-Token", s.cfg.Upstream.Token)
response, err := s.client.Do(request)
if err != nil {
http.Error(w, "platform api unavailable", 502)
return
}
defer response.Body.Close()
if response.StatusCode >= 300 {
http.Error(w, "platform api rejected message", 502)
return
}
w.WriteHeader(http.StatusAccepted)
}
func (s *Service) dispatch(ctx context.Context, cmd Command) (string, uint16, error) {
data, _ := json.Marshal(cmd)
request, err := http.NewRequestWithContext(ctx, http.MethodPost, s.cfg.Upstream.IoTServerURL+"/internal/v1/commands", bytes.NewReader(data))
if err != nil {
return "", 0, err
}
request.Header.Set("Content-Type", "application/json")
request.Header.Set("X-Heqi-Iot-Token", s.cfg.Upstream.Token)
response, err := s.client.Do(request)
if err != nil {
return "", 0, err
}
defer response.Body.Close()
if response.StatusCode != http.StatusAccepted {
body, _ := io.ReadAll(io.LimitReader(response.Body, 4096))
return "", 0, fmt.Errorf("iot server %d: %s", response.StatusCode, body)
}
var result struct {
Status string `json:"status"`
PacketNumber uint16 `json:"packet_number"`
}
if err = json.NewDecoder(response.Body).Decode(&result); err != nil {
return "", 0, err
}
return result.Status, result.PacketNumber, nil
}
func (s *Service) authorized(r *http.Request) bool {
value := r.Header.Get("X-Heqi-Iot-Token")
expected := s.cfg.HTTP.InternalToken
return len(value) == len(expected) && subtle.ConstantTimeCompare([]byte(value), []byte(expected)) == 1
}
func writeJSON(w http.ResponseWriter, status int, value any) {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(status)
_ = json.NewEncoder(w).Encode(value)
}