feat: add go realtime redis api

2026-07-01 21:51:13 +08:00
parent bac8864e79
commit b55b075a97
7 changed files with 595 additions and 0 deletions
--- a/go/vehicle-gateway/internal/realtime/http.go
+++ b/go/vehicle-gateway/internal/realtime/http.go
@@ -0,0 +1,69 @@
+package realtime
+
+import (
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strings"
+
+	"github.com/redis/go-redis/v9"
+
+	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
+)
+
+type Handler struct {
+	repository *Repository
+}
+
+func NewHandler(repository *Repository) *Handler {
+	if repository == nil {
+		panic("realtime repository must not be nil")
+	}
+	return &Handler{repository: repository}
+}
+
+func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		writeError(w, http.StatusMethodNotAllowed, "method not allowed")
+		return
+	}
+	path := strings.Trim(strings.TrimPrefix(r.URL.Path, "/api/realtime/vehicles/"), "/")
+	parts := strings.Split(path, "/")
+	if len(parts) == 0 || strings.TrimSpace(parts[0]) == "" {
+		writeError(w, http.StatusNotFound, "vehicle not found")
+		return
+	}
+	vin := parts[0]
+	switch {
+	case len(parts) == 1:
+		snapshot, err := h.repository.GetMerged(r.Context(), vin)
+		writeResult(w, snapshot, err)
+	case len(parts) == 2 && parts[1] == "online":
+		status, err := h.repository.IsOnline(r.Context(), vin)
+		writeResult(w, status, err)
+	case len(parts) == 3 && parts[1] == "protocols":
+		snapshot, err := h.repository.GetProtocol(r.Context(), vin, envelope.Protocol(strings.ToUpper(parts[2])))
+		writeResult(w, snapshot, err)
+	default:
+		writeError(w, http.StatusNotFound, "route not found")
+	}
+}
+
+func writeResult(w http.ResponseWriter, value any, err error) {
+	if err != nil {
+		if errors.Is(err, redis.Nil) {
+			writeError(w, http.StatusNotFound, "not found")
+			return
+		}
+		writeError(w, http.StatusInternalServerError, err.Error())
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	_ = json.NewEncoder(w).Encode(value)
+}
+
+func writeError(w http.ResponseWriter, status int, message string) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	_ = json.NewEncoder(w).Encode(map[string]any{"error": message})
+}
--- a/go/vehicle-gateway/internal/realtime/model.go
+++ b/go/vehicle-gateway/internal/realtime/model.go
@@ -0,0 +1,38 @@
+package realtime
+
+import (
+	"time"
+
+	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
+)
+
+type Snapshot struct {
+	VIN            string            `json:"vin"`
+	Protocol       envelope.Protocol `json:"protocol,omitempty"`
+	EventID        string            `json:"event_id,omitempty"`
+	EventTimeMS    int64             `json:"event_time_ms"`
+	ReceivedAtMS   int64             `json:"received_at_ms"`
+	SourceEndpoint string            `json:"source_endpoint,omitempty"`
+	Fields         map[string]any    `json:"fields,omitempty"`
+	FieldTimesMS   map[string]int64  `json:"field_times_ms,omitempty"`
+	UpdatedAtMS    int64             `json:"updated_at_ms"`
+}
+
+type OnlineStatus struct {
+	VIN        string              `json:"vin"`
+	Online     bool                `json:"online"`
+	LastSeenMS int64               `json:"last_seen_ms"`
+	Protocols  []envelope.Protocol `json:"protocols,omitempty"`
+	TTLSeconds int64               `json:"ttl_seconds"`
+}
+
+type Config struct {
+	OnlineTTL time.Duration
+}
+
+func (c Config) ttl() time.Duration {
+	if c.OnlineTTL <= 0 {
+		return 10 * time.Minute
+	}
+	return c.OnlineTTL
+}
--- a/go/vehicle-gateway/internal/realtime/repository.go
+++ b/go/vehicle-gateway/internal/realtime/repository.go
@@ -0,0 +1,198 @@
+package realtime
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+
+	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
+)
+
+type Repository struct {
+	client *redis.Client
+	cfg    Config
+}
+
+func NewRepository(client *redis.Client, cfg Config) *Repository {
+	if client == nil {
+		panic("redis client must not be nil")
+	}
+	return &Repository{client: client, cfg: cfg}
+}
+
+func (r *Repository) Update(ctx context.Context, env envelope.FrameEnvelope) error {
+	vin := strings.TrimSpace(env.VIN)
+	if vin == "" {
+		return nil
+	}
+	nowMS := time.Now().UnixMilli()
+	eventMS := env.EventTimeMS
+	if eventMS <= 0 {
+		eventMS = env.ReceivedAtMS
+	}
+	protocolSnapshot := Snapshot{
+		VIN:            vin,
+		Protocol:       env.Protocol,
+		EventID:        env.StableEventID(),
+		EventTimeMS:    eventMS,
+		ReceivedAtMS:   env.ReceivedAtMS,
+		SourceEndpoint: env.SourceEndpoint,
+		Fields:         cloneFields(env.Fields),
+		FieldTimesMS:   fieldTimes(env.Fields, eventMS),
+		UpdatedAtMS:    nowMS,
+	}
+	if err := r.setJSON(ctx, protocolKey(vin, env.Protocol), protocolSnapshot, r.cfg.ttl()); err != nil {
+		return err
+	}
+
+	merged, err := r.GetMerged(ctx, vin)
+	if err != nil && !errors.Is(err, redis.Nil) {
+		return err
+	}
+	if merged.VIN == "" {
+		merged = Snapshot{VIN: vin, Fields: map[string]any{}, FieldTimesMS: map[string]int64{}}
+	}
+	mergeFields(&merged, env.Fields, eventMS)
+	if eventMS >= merged.EventTimeMS {
+		merged.EventTimeMS = eventMS
+		merged.EventID = env.StableEventID()
+		merged.ReceivedAtMS = env.ReceivedAtMS
+		merged.SourceEndpoint = env.SourceEndpoint
+	}
+	merged.UpdatedAtMS = nowMS
+	if err := r.setJSON(ctx, mergedKey(vin), merged, r.cfg.ttl()); err != nil {
+		return err
+	}
+
+	protocols, err := r.addProtocol(ctx, vin, env.Protocol)
+	if err != nil {
+		return err
+	}
+	online := OnlineStatus{
+		VIN:        vin,
+		Online:     true,
+		LastSeenMS: env.ReceivedAtMS,
+		Protocols:  protocols,
+		TTLSeconds: int64(r.cfg.ttl().Seconds()),
+	}
+	if err := r.setJSON(ctx, onlineKey(vin), online, r.cfg.ttl()); err != nil {
+		return err
+	}
+	return r.client.ZAdd(ctx, "vehicle:last_seen", redis.Z{Score: float64(env.ReceivedAtMS), Member: vin}).Err()
+}
+
+func (r *Repository) GetMerged(ctx context.Context, vin string) (Snapshot, error) {
+	return r.getSnapshot(ctx, mergedKey(vin))
+}
+
+func (r *Repository) GetProtocol(ctx context.Context, vin string, protocol envelope.Protocol) (Snapshot, error) {
+	return r.getSnapshot(ctx, protocolKey(vin, protocol))
+}
+
+func (r *Repository) IsOnline(ctx context.Context, vin string) (OnlineStatus, error) {
+	var status OnlineStatus
+	payload, err := r.client.Get(ctx, onlineKey(vin)).Bytes()
+	if err != nil {
+		if errors.Is(err, redis.Nil) {
+			return OnlineStatus{VIN: vin, Online: false}, nil
+		}
+		return status, err
+	}
+	if err := json.Unmarshal(payload, &status); err != nil {
+		return status, err
+	}
+	ttl := r.client.TTL(ctx, onlineKey(vin)).Val()
+	status.Online = ttl > 0
+	status.TTLSeconds = int64(ttl.Seconds())
+	return status, nil
+}
+
+func (r *Repository) getSnapshot(ctx context.Context, key string) (Snapshot, error) {
+	var snapshot Snapshot
+	payload, err := r.client.Get(ctx, key).Bytes()
+	if err != nil {
+		return snapshot, err
+	}
+	return snapshot, json.Unmarshal(payload, &snapshot)
+}
+
+func (r *Repository) setJSON(ctx context.Context, key string, value any, ttl time.Duration) error {
+	payload, err := json.Marshal(value)
+	if err != nil {
+		return err
+	}
+	return r.client.Set(ctx, key, payload, ttl).Err()
+}
+
+func (r *Repository) addProtocol(ctx context.Context, vin string, protocol envelope.Protocol) ([]envelope.Protocol, error) {
+	key := protocolsKey(vin)
+	if err := r.client.SAdd(ctx, key, string(protocol)).Err(); err != nil {
+		return nil, err
+	}
+	_ = r.client.Expire(ctx, key, r.cfg.ttl()).Err()
+	values, err := r.client.SMembers(ctx, key).Result()
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(values)
+	out := make([]envelope.Protocol, 0, len(values))
+	for _, value := range values {
+		out = append(out, envelope.Protocol(value))
+	}
+	return out, nil
+}
+
+func mergeFields(snapshot *Snapshot, fields map[string]any, eventMS int64) {
+	if snapshot.Fields == nil {
+		snapshot.Fields = map[string]any{}
+	}
+	if snapshot.FieldTimesMS == nil {
+		snapshot.FieldTimesMS = map[string]int64{}
+	}
+	for key, value := range fields {
+		if eventMS >= snapshot.FieldTimesMS[key] {
+			snapshot.Fields[key] = value
+			snapshot.FieldTimesMS[key] = eventMS
+		}
+	}
+}
+
+func cloneFields(fields map[string]any) map[string]any {
+	if len(fields) == 0 {
+		return map[string]any{}
+	}
+	out := make(map[string]any, len(fields))
+	for key, value := range fields {
+		out[key] = value
+	}
+	return out
+}
+
+func fieldTimes(fields map[string]any, eventMS int64) map[string]int64 {
+	out := make(map[string]int64, len(fields))
+	for key := range fields {
+		out[key] = eventMS
+	}
+	return out
+}
+
+func mergedKey(vin string) string {
+	return "vehicle:latest:" + strings.TrimSpace(vin)
+}
+
+func protocolKey(vin string, protocol envelope.Protocol) string {
+	return "vehicle:latest:" + strings.TrimSpace(vin) + ":" + string(protocol)
+}
+
+func onlineKey(vin string) string {
+	return "vehicle:online:" + strings.TrimSpace(vin)
+}
+
+func protocolsKey(vin string) string {
+	return "vehicle:protocols:" + strings.TrimSpace(vin)
+}
--- a/go/vehicle-gateway/internal/realtime/repository_test.go
+++ b/go/vehicle-gateway/internal/realtime/repository_test.go
@@ -0,0 +1,136 @@
+package realtime
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/alicebob/miniredis/v2"
+	"github.com/redis/go-redis/v9"
+
+	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
+)
+
+func TestRepositoryUpdatesMergedAndProtocolSnapshots(t *testing.T) {
+	repo, closeFn := newTestRepository(t)
+	defer closeFn()
+	ctx := context.Background()
+
+	if err := repo.Update(ctx, envelope.FrameEnvelope{
+		Protocol:     envelope.ProtocolJT808,
+		VIN:          "VIN001",
+		EventTimeMS:  1000,
+		ReceivedAtMS: 1100,
+		Fields: map[string]any{
+			envelope.FieldLongitude:      121.1,
+			envelope.FieldTotalMileageKM: 10.5,
+		},
+	}); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+	if err := repo.Update(ctx, envelope.FrameEnvelope{
+		Protocol:     envelope.ProtocolGB32960,
+		VIN:          "VIN001",
+		EventTimeMS:  900,
+		ReceivedAtMS: 1200,
+		Fields: map[string]any{
+			envelope.FieldLongitude: 120.0,
+			envelope.FieldLatitude:  30.5,
+		},
+	}); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+
+	merged, err := repo.GetMerged(ctx, "VIN001")
+	if err != nil {
+		t.Fatalf("GetMerged() error = %v", err)
+	}
+	if merged.Fields[envelope.FieldLongitude] != 121.1 {
+		t.Fatalf("older longitude overwrote newer value: %#v", merged.Fields)
+	}
+	if merged.Fields[envelope.FieldLatitude] != 30.5 {
+		t.Fatalf("new latitude missing: %#v", merged.Fields)
+	}
+	protocol, err := repo.GetProtocol(ctx, "VIN001", envelope.ProtocolJT808)
+	if err != nil {
+		t.Fatalf("GetProtocol() error = %v", err)
+	}
+	if protocol.Fields[envelope.FieldTotalMileageKM] != 10.5 {
+		t.Fatalf("protocol snapshot = %#v", protocol)
+	}
+}
+
+func TestRepositoryOnlineStatus(t *testing.T) {
+	repo, closeFn := newTestRepository(t)
+	defer closeFn()
+	ctx := context.Background()
+
+	status, err := repo.IsOnline(ctx, "VIN001")
+	if err != nil {
+		t.Fatalf("IsOnline() error = %v", err)
+	}
+	if status.Online {
+		t.Fatal("empty vin should be offline")
+	}
+
+	if err := repo.Update(ctx, envelope.FrameEnvelope{
+		Protocol:     envelope.ProtocolJT808,
+		VIN:          "VIN001",
+		EventTimeMS:  1000,
+		ReceivedAtMS: 1100,
+		Fields:       map[string]any{envelope.FieldSpeedKMH: 12.3},
+	}); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+	status, err = repo.IsOnline(ctx, "VIN001")
+	if err != nil {
+		t.Fatalf("IsOnline() error = %v", err)
+	}
+	if !status.Online || status.LastSeenMS != 1100 {
+		t.Fatalf("online status = %#v", status)
+	}
+}
+
+func TestHandlerReturnsMergedSnapshot(t *testing.T) {
+	repo, closeFn := newTestRepository(t)
+	defer closeFn()
+	if err := repo.Update(context.Background(), envelope.FrameEnvelope{
+		Protocol:     envelope.ProtocolJT808,
+		VIN:          "VIN001",
+		EventTimeMS:  1000,
+		ReceivedAtMS: 1100,
+		Fields:       map[string]any{envelope.FieldSpeedKMH: 12.3},
+	}); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+
+	req := httptest.NewRequest(http.MethodGet, "/api/realtime/vehicles/VIN001", nil)
+	rec := httptest.NewRecorder()
+	NewHandler(repo).ServeHTTP(rec, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d body=%s", rec.Code, rec.Body.String())
+	}
+	if !stringsContains(rec.Body.String(), `"vin":"VIN001"`) {
+		t.Fatalf("unexpected body: %s", rec.Body.String())
+	}
+}
+
+func newTestRepository(t *testing.T) (*Repository, func()) {
+	t.Helper()
+	server, err := miniredis.Run()
+	if err != nil {
+		t.Fatalf("miniredis.Run() error = %v", err)
+	}
+	client := redis.NewClient(&redis.Options{Addr: server.Addr()})
+	return NewRepository(client, Config{OnlineTTL: time.Minute}), func() {
+		_ = client.Close()
+		server.Close()
+	}
+}
+
+func stringsContains(value string, pattern string) bool {
+	return strings.Contains(value, pattern)
+}