generate excel worksheets when data is available instead of on-demand

internal/report/snapshots.go

@@ -6,6 +6,8 @@ import (
 	"database/sql"
 	"fmt"
 	"log/slog"
+	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
@@ -637,6 +639,29 @@ func CreateTableReport(logger *slog.Logger, Database db.Database, ctx context.Co
 	return buffer.Bytes(), nil
 }
 
+// SaveTableReport renders a table report and writes it to the destination directory with a .xlsx extension.
+func SaveTableReport(logger *slog.Logger, Database db.Database, ctx context.Context, tableName, destDir string) (string, error) {
+	if err := db.ValidateTableName(tableName); err != nil {
+		return "", err
+	}
+	if strings.TrimSpace(destDir) == "" {
+		return "", fmt.Errorf("destination directory is empty")
+	}
+	if err := os.MkdirAll(destDir, 0o755); err != nil {
+		return "", fmt.Errorf("failed to create reports directory: %w", err)
+	}
+
+	data, err := CreateTableReport(logger, Database, ctx, tableName)
+	if err != nil {
+		return "", err
+	}
+	filename := filepath.Join(destDir, fmt.Sprintf("%s.xlsx", tableName))
+	if err := os.WriteFile(filename, data, 0o644); err != nil {
+		return "", err
+	}
+	return filename, nil
+}
+
 func addTotalsChartSheet(logger *slog.Logger, database db.Database, ctx context.Context, xlsx *excelize.File, tableName string) {
 	if strings.HasPrefix(tableName, "inventory_daily_summary_") {
 		suffix := strings.TrimPrefix(tableName, "inventory_daily_summary_")

internal/settings/settings.go

@@ -40,6 +40,7 @@ type SettingsYML struct {
 		HourlySnapshotMaxAgeDays         int      `yaml:"hourly_snapshot_max_age_days"`
 		DailySnapshotMaxAgeMonths        int      `yaml:"daily_snapshot_max_age_months"`
 		SnapshotCleanupCron              string   `yaml:"snapshot_cleanup_cron"`
+		ReportsDir                       string   `yaml:"reports_dir"`
 		HourlyJobTimeoutSeconds          int      `yaml:"hourly_job_timeout_seconds"`
 		HourlySnapshotTimeoutSeconds     int      `yaml:"hourly_snapshot_timeout_seconds"`
 		DailyJobTimeoutSeconds           int      `yaml:"daily_job_timeout_seconds"`

internal/tasks/inventorySnapshots.go

@@ -168,6 +168,10 @@ func (c *CronTask) RunVcenterSnapshotHourly(ctx context.Context, logger *slog.Lo
 		c.Logger.Warn("failed to register hourly snapshot", "error", err, "table", tableName)
 	}
 
+	if err := c.generateReport(ctx, tableName); err != nil {
+		c.Logger.Warn("failed to generate hourly report", "error", err, "table", tableName)
+	}
+
 	c.Logger.Debug("Finished hourly vcenter snapshot", "vcenter_count", len(c.Settings.Values.Settings.VcenterAddresses), "table", tableName, "row_count", rowCount)
 	return nil
 }
@@ -312,6 +316,10 @@ func (c *CronTask) aggregateDailySummary(ctx context.Context, targetTime time.Ti
 		c.Logger.Warn("failed to register daily snapshot", "error", err, "table", summaryTable)
 	}
 
+	if err := c.generateReport(ctx, summaryTable); err != nil {
+		c.Logger.Warn("failed to generate daily report", "error", err, "table", summaryTable)
+	}
+
 	c.Logger.Debug("Finished daily inventory aggregation", "summary_table", summaryTable)
 	return nil
 }
@@ -431,6 +439,10 @@ func (c *CronTask) aggregateMonthlySummary(ctx context.Context, targetMonth time
 		c.Logger.Warn("failed to register monthly snapshot", "error", err, "table", monthlyTable)
 	}
 
+	if err := c.generateReport(ctx, monthlyTable); err != nil {
+		c.Logger.Warn("failed to generate monthly report", "error", err, "table", monthlyTable)
+	}
+
 	c.Logger.Debug("Finished monthly inventory aggregation", "summary_table", monthlyTable)
 	return nil
 }
@@ -718,6 +730,21 @@ func normalizeResourcePool(value string) string {
 	}
 }
 
+func (c *CronTask) reportsDir() string {
+	if c.Settings != nil && c.Settings.Values != nil {
+		if dir := strings.TrimSpace(c.Settings.Values.Settings.ReportsDir); dir != "" {
+			return dir
+		}
+	}
+	return "/var/lib/vctp/reports"
+}
+
+func (c *CronTask) generateReport(ctx context.Context, tableName string) error {
+	dest := c.reportsDir()
+	_, err := report.SaveTableReport(c.Logger, c.Database, ctx, tableName, dest)
+	return err
+}
+
 func snapshotFromVM(vmObject *mo.VirtualMachine, vc *vcenter.Vcenter, snapshotTime time.Time, inv *queries.Inventory, hostLookup map[string]vcenter.HostLookup, folderLookup vcenter.FolderLookup, rpLookup map[string]string) (inventorySnapshotRow, error) {
 	if vmObject == nil {
 		return inventorySnapshotRow{}, fmt.Errorf("missing VM object")

server/handler/snapshots.go

@@ -111,7 +111,7 @@ func (h *Handler) renderSnapshotList(w http.ResponseWriter, r *http.Request, sna
 		label := report.FormatSnapshotLabel(snapshotType, record.SnapshotTime, record.TableName)
 		entries = append(entries, views.SnapshotEntry{
 			Label: label,
-			Link:  "/api/report/snapshot?table=" + url.QueryEscape(record.TableName),
+			Link:  "/reports/" + url.PathEscape(record.TableName) + ".xlsx",
 			Count: record.SnapshotCount,
 		})
 	}

server/router/router.go

@@ -5,6 +5,8 @@ import (
 	"log/slog"
 	"net/http"
 	"net/http/pprof"
+	"os"
+	"path/filepath"
 	"vctp/db"
 	"vctp/dist"
 	"vctp/internal/secrets"
@@ -28,10 +30,19 @@ func New(logger *slog.Logger, database db.Database, buildTime string, sha1ver st
 
 	mux := http.NewServeMux()
 
+	reportsDir := settings.Values.Settings.ReportsDir
+	if reportsDir == "" {
+		reportsDir = "/var/lib/vctp/reports"
+	}
+	if err := os.MkdirAll(reportsDir, 0o755); err != nil {
+		logger.Warn("failed to create reports directory", "error", err, "path", reportsDir)
+	}
+
 	mux.Handle("/assets/", middleware.CacheMiddleware(http.FileServer(http.FS(dist.AssetsDir))))
 	mux.Handle("/favicon.ico", middleware.CacheMiddleware(http.FileServer(http.FS(dist.AssetsDir))))
 	mux.Handle("/favicon-16x16.png", middleware.CacheMiddleware(http.FileServer(http.FS(dist.AssetsDir))))
 	mux.Handle("/favicon-32x32.png", middleware.CacheMiddleware(http.FileServer(http.FS(dist.AssetsDir))))
+	mux.Handle("/reports/", http.StripPrefix("/reports/", http.FileServer(http.Dir(filepath.Clean(reportsDir)))))
 	mux.HandleFunc("/", h.Home)
 	mux.HandleFunc("/api/event/vm/create", h.VmCreateEvent)
 	mux.HandleFunc("/api/event/vm/modify", h.VmModifyEvent)

src/preinstall.sh

@@ -20,6 +20,7 @@ getent passwd "$USER" >/dev/null || useradd -r -g "$GROUP" -m -s /bin/bash -c "v
 
 # create vctp data directory if it doesn't exist
 [ -d /var/lib/vctp ] || mkdir -p /var/lib/vctp
+[ -d /var/lib/vctp/reports ] || mkdir -p /var/lib/vctp/reports
 
 # set user ownership on vctp data directory if not already done
 [ "$(stat -c "%U" /var/lib/vctp)" = "$USER" ] || chown -R "$USER" /var/lib/vctp

src/vctp.yml

@@ -3,6 +3,7 @@ settings:
   log_output: "text"
   database_driver: "sqlite"
   database_url: "/var/lib/vctp/db.sqlite3"
+  reports_dir: /var/lib/vctp/reports  
   bind_ip:
   bind_port: 9443
   bind_disable_tls: false