FEATURE (metrics): Add metrics

Author: RostislavDugin

backend/cmd/main.go

@@ -20,6 +20,8 @@ import (
 	"postgresus-backend/internal/features/disk"
 	healthcheck_attempt "postgresus-backend/internal/features/healthcheck/attempt"
 	healthcheck_config "postgresus-backend/internal/features/healthcheck/config"
+	postgres_monitoring_metrics "postgresus-backend/internal/features/monitoring/postgres/metrics"
+	postgres_monitoring_settings "postgresus-backend/internal/features/monitoring/postgres/settings"
 	"postgresus-backend/internal/features/notifiers"
 	"postgresus-backend/internal/features/restores"
 	"postgresus-backend/internal/features/storages"
@@ -158,6 +160,8 @@ func setUpRoutes(r *gin.Engine) {
 	healthcheckAttemptController := healthcheck_attempt.GetHealthcheckAttemptController()
 	diskController := disk.GetDiskController()
 	backupConfigController := backups_config.GetBackupConfigController()
+	postgresMonitoringSettingsController := postgres_monitoring_settings.GetPostgresMonitoringSettingsController()
+	postgresMonitoringMetricsController := postgres_monitoring_metrics.GetPostgresMonitoringMetricsController()
 
 	downdetectContoller.RegisterRoutes(v1)
 	userController.RegisterRoutes(v1)
@@ -171,13 +175,16 @@ func setUpRoutes(r *gin.Engine) {
 	healthcheckConfigController.RegisterRoutes(v1)
 	healthcheckAttemptController.RegisterRoutes(v1)
 	backupConfigController.RegisterRoutes(v1)
+	postgresMonitoringSettingsController.RegisterRoutes(v1)
+	postgresMonitoringMetricsController.RegisterRoutes(v1)
 }
 
 func setUpDependencies() {
 	backups.SetupDependencies()
 	backups.SetupDependencies()
 	restores.SetupDependencies()
 	healthcheck_config.SetupDependencies()
+	postgres_monitoring_settings.SetupDependencies()
 }
 
 func runBackgroundTasks(log *slog.Logger) {
@@ -199,6 +206,10 @@ func runBackgroundTasks(log *slog.Logger) {
 	go runWithPanicLogging(log, "healthcheck attempt background service", func() {
 		healthcheck_attempt.GetHealthcheckAttemptBackgroundService().RunBackgroundTasks()
 	})
+
+	go runWithPanicLogging(log, "postgres monitoring metrics background service", func() {
+		postgres_monitoring_metrics.GetPostgresMonitoringMetricsBackgroundService().Run()
+	})
 }
 
 func runWithPanicLogging(log *slog.Logger, serviceName string, fn func()) {

backend/internal/features/databases/databases/postgresql/model.go

@@ -7,6 +7,7 @@ import (
 	"log/slog"
 	"postgresus-backend/internal/util/tools"
 	"regexp"
+	"slices"
 	"time"
 
 	"github.com/google/uuid"
@@ -175,3 +176,101 @@ func buildConnectionStringForDB(p *PostgresqlDatabase, dbName string) string {
 		sslMode,
 	)
 }
+
+func (p *PostgresqlDatabase) InstallExtensions(extensions []tools.PostgresqlExtension) error {
+	if len(extensions) == 0 {
+		return nil
+	}
+
+	if p.Database == nil || *p.Database == "" {
+		return errors.New("database name is required for installing extensions")
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	// Build connection string for the specific database
+	connStr := buildConnectionStringForDB(p, *p.Database)
+
+	// Connect to database
+	conn, err := pgx.Connect(ctx, connStr)
+	if err != nil {
+		return fmt.Errorf("failed to connect to database '%s': %w", *p.Database, err)
+	}
+	defer func() {
+		if closeErr := conn.Close(ctx); closeErr != nil {
+			fmt.Println("failed to close connection: %w", closeErr)
+		}
+	}()
+
+	// Check which extensions are already installed
+	installedExtensions, err := p.getInstalledExtensions(ctx, conn)
+	if err != nil {
+		return fmt.Errorf("failed to check installed extensions: %w", err)
+	}
+
+	// Install missing extensions
+	for _, extension := range extensions {
+		if contains(installedExtensions, string(extension)) {
+			continue // Extension already installed
+		}
+
+		if err := p.installExtension(ctx, conn, string(extension)); err != nil {
+			return fmt.Errorf("failed to install extension '%s': %w", extension, err)
+		}
+	}
+
+	return nil
+}
+
+// getInstalledExtensions queries the database for currently installed extensions
+func (p *PostgresqlDatabase) getInstalledExtensions(
+	ctx context.Context,
+	conn *pgx.Conn,
+) ([]string, error) {
+	query := "SELECT extname FROM pg_extension"
+
+	rows, err := conn.Query(ctx, query)
+	if err != nil {
+		return nil, fmt.Errorf("failed to query installed extensions: %w", err)
+	}
+	defer rows.Close()
+
+	var extensions []string
+	for rows.Next() {
+		var extname string
+
+		if err := rows.Scan(&extname); err != nil {
+			return nil, fmt.Errorf("failed to scan extension name: %w", err)
+		}
+
+		extensions = append(extensions, extname)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("error iterating over extension rows: %w", err)
+	}
+
+	return extensions, nil
+}
+
+// installExtension installs a single PostgreSQL extension
+func (p *PostgresqlDatabase) installExtension(
+	ctx context.Context,
+	conn *pgx.Conn,
+	extensionName string,
+) error {
+	query := fmt.Sprintf("CREATE EXTENSION IF NOT EXISTS %s", extensionName)
+
+	_, err := conn.Exec(ctx, query)
+	if err != nil {
+		return fmt.Errorf("failed to execute CREATE EXTENSION: %w", err)
+	}
+
+	return nil
+}
+
+// contains checks if a string slice contains a specific string
+func contains(slice []string, item string) bool {
+	return slices.Contains(slice, item)
+}

backend/internal/features/monitoring/postgres/collectors/db_monitoring_service.go

@@ -0,0 +1,3 @@
+package postgres_monitoring_collectors
+
+type DbMonitoringBackgroundService struct{}

backend/internal/features/monitoring/postgres/collectors/system_monitoring_service.go

@@ -0,0 +1,3 @@
+package postgres_monitoring_collectors
+
+type SystemMonitoringBackgroundService struct{}

backend/internal/features/monitoring/postgres/metrics/background_service.go

@@ -0,0 +1,33 @@
+package postgres_monitoring_metrics
+
+import (
+	"postgresus-backend/internal/config"
+	"postgresus-backend/internal/util/logger"
+	"time"
+)
+
+var log = logger.GetLogger()
+
+type PostgresMonitoringMetricsBackgroundService struct {
+	metricsRepository *PostgresMonitoringMetricRepository
+}
+
+func (s *PostgresMonitoringMetricsBackgroundService) Run() {
+	for {
+		if config.IsShouldShutdown() {
+			return
+		}
+
+		s.RemoveOldMetrics()
+
+		time.Sleep(5 * time.Minute)
+	}
+}
+
+func (s *PostgresMonitoringMetricsBackgroundService) RemoveOldMetrics() {
+	monthAgo := time.Now().UTC().Add(-3 * 30 * 24 * time.Hour)
+
+	if err := s.metricsRepository.RemoveOlderThan(monthAgo); err != nil {
+		log.Error("Failed to remove old metrics", "error", err)
+	}
+}

backend/internal/features/monitoring/postgres/metrics/controller.go

@@ -0,0 +1,62 @@
+package postgres_monitoring_metrics
+
+import (
+	"net/http"
+	"postgresus-backend/internal/features/users"
+
+	"github.com/gin-gonic/gin"
+)
+
+type PostgresMonitoringMetricsController struct {
+	metricsService *PostgresMonitoringMetricService
+	userService    *users.UserService
+}
+
+func (c *PostgresMonitoringMetricsController) RegisterRoutes(router *gin.RouterGroup) {
+	router.POST("/postgres-monitoring-metrics/get", c.GetMetrics)
+}
+
+// GetMetrics
+// @Summary Get postgres monitoring metrics
+// @Description Get postgres monitoring metrics for a database within a time range
+// @Tags postgres-monitoring-metrics
+// @Accept json
+// @Produce json
+// @Param request body GetMetricsRequest true "Metrics request data"
+// @Success 200 {object} []PostgresMonitoringMetric
+// @Failure 400
+// @Failure 401
+// @Router /postgres-monitoring-metrics/get [post]
+func (c *PostgresMonitoringMetricsController) GetMetrics(ctx *gin.Context) {
+	var requestDTO GetMetricsRequest
+	if err := ctx.ShouldBindJSON(&requestDTO); err != nil {
+		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	authorizationHeader := ctx.GetHeader("Authorization")
+	if authorizationHeader == "" {
+		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "authorization header is required"})
+		return
+	}
+
+	user, err := c.userService.GetUserFromToken(authorizationHeader)
+	if err != nil {
+		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "invalid token"})
+		return
+	}
+
+	metrics, err := c.metricsService.GetMetrics(
+		user,
+		requestDTO.DatabaseID,
+		requestDTO.MetricType,
+		requestDTO.From,
+		requestDTO.To,
+	)
+	if err != nil {
+		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	ctx.JSON(http.StatusOK, metrics)
+}

backend/internal/features/monitoring/postgres/metrics/di.go

@@ -0,0 +1,35 @@
+package postgres_monitoring_metrics
+
+import (
+	"postgresus-backend/internal/features/databases"
+	"postgresus-backend/internal/features/users"
+)
+
+var metricsRepository = &PostgresMonitoringMetricRepository{}
+var metricsService = &PostgresMonitoringMetricService{
+	metricsRepository,
+	databases.GetDatabaseService(),
+}
+var metricsController = &PostgresMonitoringMetricsController{
+	metricsService,
+	users.GetUserService(),
+}
+var metricsBackgroundService = &PostgresMonitoringMetricsBackgroundService{
+	metricsRepository,
+}
+
+func GetPostgresMonitoringMetricsController() *PostgresMonitoringMetricsController {
+	return metricsController
+}
+
+func GetPostgresMonitoringMetricsService() *PostgresMonitoringMetricService {
+	return metricsService
+}
+
+func GetPostgresMonitoringMetricsRepository() *PostgresMonitoringMetricRepository {
+	return metricsRepository
+}
+
+func GetPostgresMonitoringMetricsBackgroundService() *PostgresMonitoringMetricsBackgroundService {
+	return metricsBackgroundService
+}

backend/internal/features/monitoring/postgres/metrics/dto.go

@@ -0,0 +1,14 @@
+package postgres_monitoring_metrics
+
+import (
+	"time"
+
+	"github.com/google/uuid"
+)
+
+type GetMetricsRequest struct {
+	DatabaseID uuid.UUID                    `json:"databaseId" binding:"required"`
+	MetricType PostgresMonitoringMetricType `json:"metricType"`
+	From       time.Time                    `json:"from"       binding:"required"`
+	To         time.Time                    `json:"to"         binding:"required"`
+}

backend/internal/features/monitoring/postgres/metrics/enums.go

@@ -0,0 +1,22 @@
+package postgres_monitoring_metrics
+
+type PostgresMonitoringMetricType string
+
+const (
+	// system resources (need extensions)
+	MetricsTypeSystemCPU PostgresMonitoringMetricType = "SYSTEM_CPU_USAGE"
+	MetricsTypeSystemRAM PostgresMonitoringMetricType = "SYSTEM_RAM_USAGE"
+	MetricsTypeSystemROM PostgresMonitoringMetricType = "SYSTEM_ROM_USAGE"
+	MetricsTypeSystemIO  PostgresMonitoringMetricType = "SYSTEM_IO_USAGE"
+	// db resources (don't need extensions)
+	MetricsTypeDbRAM PostgresMonitoringMetricType = "DB_RAM_USAGE"
+	MetricsTypeDbROM PostgresMonitoringMetricType = "DB_ROM_USAGE"
+	MetricsTypeDbIO  PostgresMonitoringMetricType = "DB_IO_USAGE"
+)
+
+type PostgresMonitoringMetricValueType string
+
+const (
+	MetricsValueTypeByte    PostgresMonitoringMetricValueType = "BYTE"
+	MetricsValueTypePercent PostgresMonitoringMetricValueType = "PERCENT"
+)

backend/internal/features/monitoring/postgres/metrics/model.go

@@ -0,0 +1,20 @@
+package postgres_monitoring_metrics
+
+import (
+	"time"
+
+	"github.com/google/uuid"
+)
+
+type PostgresMonitoringMetric struct {
+	ID         uuid.UUID                         `json:"id"         gorm:"column:id;primaryKey;type:uuid;default:gen_random_uuid()"`
+	DatabaseID uuid.UUID                         `json:"databaseId" gorm:"column:database_id;not null;type:uuid"`
+	Metric     PostgresMonitoringMetricType      `json:"metric"     gorm:"column:metric;not null"`
+	ValueType  PostgresMonitoringMetricValueType `json:"valueType"  gorm:"column:value_type;not null"`
+	Value      float64                           `json:"value"      gorm:"column:value;not null"`
+	CreatedAt  time.Time                         `json:"createdAt"  gorm:"column:created_at;not null"`
+}
+
+func (p *PostgresMonitoringMetric) TableName() string {
+	return "postgres_monitoring_metrics"
+}