feat(db): implement PostgreSQL monitoring and maintenance features

Added PostgreSQL monitoring and maintenance capabilities to the API, including new endpoints for instance-level metrics, maintenance operations, and job scheduling. Updated the HTTP API to support PostgreSQL monitoring routes and integrated a background scheduler for metrics collection. Enhanced the CLI with database commands for maintenance tasks. Updated documentation to reflect these changes.

internal/jobs/postgres_worker.go

@@ -0,0 +1,169 @@
+package jobs
+
+import (
+	"fmt"
+	"strings"
+
+	"evobgp/internal/pgmonitor"
+)
+
+func (w *Worker) pgService() *pgmonitor.Service {
+	if w == nil || w.PgPool == nil {
+		return nil
+	}
+	return pgmonitor.NewService(w.PgPool)
+}
+
+func (w *Worker) runPostgresMetricsRefresh(j *Job) {
+	s := w.pgService()
+	if s == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	ctx, cancel := j.workContext()
+	defer cancel()
+	if err := s.RefreshMetricsSnapshot(ctx); err != nil {
+		j.Fail(err.Error())
+		return
+	}
+	j.Succeed()
+}
+
+func (w *Worker) runPostgresSlowQueryAgg(j *Job) {
+	s := w.pgService()
+	if s == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	ctx, cancel := j.workContext()
+	defer cancel()
+	if err := s.AggregateSlowQueries(ctx, 30); err != nil {
+		j.Fail(err.Error())
+		return
+	}
+	j.Succeed()
+}
+
+func (w *Worker) runPostgresTableBloat(j *Job) {
+	s := w.pgService()
+	if s == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	ctx, cancel := j.workContext()
+	defer cancel()
+	if err := s.EstimateTableBloat(ctx); err != nil {
+		j.Fail(err.Error())
+		return
+	}
+	j.Succeed()
+}
+
+func (w *Worker) runPostgresIndexUsage(j *Job) {
+	s := w.pgService()
+	if s == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	ctx, cancel := j.workContext()
+	defer cancel()
+	if err := s.AnalyzeIndexUsage(ctx); err != nil {
+		j.Fail(err.Error())
+		return
+	}
+	j.Succeed()
+}
+
+func (w *Worker) runPostgresAutovacuumLag(j *Job) {
+	s := w.pgService()
+	if s == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	ctx, cancel := j.workContext()
+	defer cancel()
+	if err := s.DetectAutovacuumLag(ctx); err != nil {
+		j.Fail(err.Error())
+		return
+	}
+	j.Succeed()
+}
+
+func (w *Worker) runPostgresMaint(j *Job, kind string) {
+	if w == nil || w.PgPool == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	table, _ := j.Meta["table"].(string)
+	dryRun, _ := j.Meta["dry_run"].(bool)
+	actor, _ := j.Meta["actor_prefix"].(string)
+	ctx, cancel := j.workContext()
+	defer cancel()
+	auditID, _ := pgmonitor.InsertMaintenanceAudit(ctx, w.PgPool, j.TenantID, actor, kind, table, dryRun)
+	detail, err := pgmonitor.ExecMaintenance(ctx, w.PgPool, kind, table, dryRun)
+	var errMsg *string
+	status := StatusSucceeded
+	if err != nil {
+		s := err.Error()
+		errMsg = &s
+		status = StatusFailed
+		j.Fail(s)
+	} else {
+		j.mergeMeta(map[string]any{"maintenance": detail, "audit_id": auditID})
+		j.Succeed()
+	}
+	if auditID != "" {
+		_ = pgmonitor.FinishMaintenanceAudit(ctx, w.PgPool, auditID, status, detail, errMsg)
+	}
+}
+
+func (w *Worker) runPostgresCleanup(j *Job) {
+	if w == nil || w.PgPool == nil {
+		j.Fail("postgresql not configured")
+		return
+	}
+	policy, _ := j.Meta["policy"].(string)
+	dryRun, _ := j.Meta["dry_run"].(bool)
+	limit := 0
+	if v, ok := j.Meta["limit"].(float64); ok {
+		limit = int(v)
+	}
+	actor, _ := j.Meta["actor_prefix"].(string)
+	ctx, cancel := j.workContext()
+	defer cancel()
+	auditID, _ := pgmonitor.InsertMaintenanceAudit(ctx, w.PgPool, j.TenantID, actor, "cleanup", policy, dryRun)
+	detail, err := pgmonitor.RunCleanup(ctx, w.PgPool, strings.TrimSpace(policy), dryRun, limit)
+	var errMsg *string
+	status := StatusSucceeded
+	if err != nil {
+		s := err.Error()
+		errMsg = &s
+		status = StatusFailed
+		j.Fail(s)
+	} else {
+		j.mergeMeta(map[string]any{"cleanup": detail, "audit_id": auditID})
+		j.Succeed()
+	}
+	if auditID != "" {
+		_ = pgmonitor.FinishMaintenanceAudit(ctx, w.PgPool, auditID, status, detail, errMsg)
+	}
+}
+
+// EnqueuePostgresAnalyzerJobs enqueues periodic analyzer jobs (global tenant id).
+func EnqueuePostgresAnalyzerJobs(reg *Registry, tenantID string) {
+	if reg == nil || tenantID == "" {
+		return
+	}
+	kinds := []string{
+		KindPostgresMetricsRefresh,
+		KindPostgresSlowQueryAgg,
+		KindPostgresTableBloat,
+		KindPostgresIndexUsage,
+		KindPostgresAutovacuumLag,
+	}
+	for _, k := range kinds {
+		key := fmt.Sprintf("pgmon-%s-%s", k, tenantID)
+		idem := key
+		_, _, _ = reg.Enqueue(tenantID, k, &idem, nil, map[string]any{"trigger": "scheduler"})
+	}
+}