Remove so-telegraf-trim and update retention description

pg_partman drops old partitions hourly; row-DELETE retention is
obsolete and a confusing emergency fallback on partitioned tables.

salt/postgres/soc_postgres.yaml

@@ -1,7 +1,7 @@
 postgres:
   telegraf:
     retention_days:
-      description: Number of days of Telegraf metrics to keep in the so_telegraf database. Older rows are deleted nightly by so-telegraf-trim.
+      description: Number of days of Telegraf metrics to keep in the so_telegraf database. Older partitions are dropped hourly by pg_partman.
       forcedType: int
       advanced: True
       helpLink: influxdb

salt/postgres/tools/sbin/so-telegraf-trim

@@ -1,103 +0,0 @@
-#!/bin/bash
-
-# Copyright Security Onion Solutions LLC and/or licensed to Security Onion Solutions LLC under one
-# or more contributor license agreements. Licensed under the Elastic License 2.0 as shown at
-# https://securityonion.net/license; you may not use this file except in compliance with the
-# Elastic License 2.0.
-
-# Deletes Telegraf metric rows older than the configured retention window from
-# every minion schema in the so_telegraf database. Intended to run daily from
-# cron. Retention comes from pillar (postgres.telegraf.retention_days),
-# defaulting to 14 days. An explicit --days argument overrides the pillar.
-
-. /usr/sbin/so-common
-
-usage() {
-  cat <<EOF
-Usage: $0 [--days N] [--dry-run]
-
-  --days N    Override retention in days (default: pillar
-              postgres.telegraf.retention_days, fallback 14)
-  --dry-run   Report what would be deleted without modifying anything
-EOF
-  exit 1
-}
-
-if [ "$(id -u)" -ne 0 ]; then
-  echo "This script must be run using sudo!"
-  exit 1
-fi
-
-DAYS=""
-DRY_RUN=0
-while [ $# -gt 0 ]; do
-  case "$1" in
-    --days) DAYS="$2"; shift 2 ;;
-    --dry-run) DRY_RUN=1; shift ;;
-    -h|--help) usage ;;
-    *) usage ;;
-  esac
-done
-
-if [ -z "$DAYS" ]; then
-  DAYS=$(salt-call --local --out=newline_values_only pillar.get postgres:telegraf:retention_days 2>/dev/null)
-fi
-if ! [[ "$DAYS" =~ ^[0-9]+$ ]] || [ "$DAYS" -lt 1 ]; then
-  DAYS=14
-fi
-
-log() {
-  echo "$(date '+%Y-%m-%d %H:%M:%S') so-telegraf-trim: $*"
-}
-
-so_psql() {
-  docker exec so-postgres psql -U postgres -d so_telegraf -At -F $'\t' "$@"
-}
-
-if ! docker exec so-postgres psql -U postgres -lqt 2>/dev/null | cut -d\| -f1 | grep -qw so_telegraf; then
-  log "Database so_telegraf not present; nothing to trim."
-  exit 0
-fi
-
-log "Trimming rows older than ${DAYS} days (dry_run=${DRY_RUN})."
-
-TOTAL_DELETED=0
-
-# Every metric table in the shared telegraf schema has a 'time' column.
-# Tag tables (<metric>_tag) don't, so filtering on the column presence is
-# enough to scope the trim to metric tables only.
-ROWS=$(so_psql -c "
-  SELECT table_schema || '.' || table_name
-  FROM information_schema.columns
-  WHERE column_name = 'time'
-    AND data_type IN ('timestamp with time zone', 'timestamp without time zone')
-    AND table_schema = 'telegraf'
-  ORDER BY 1;")
-
-if [ -z "$ROWS" ]; then
-  log "No telegraf metric tables found."
-  exit 0
-fi
-
-for qualified in $ROWS; do
-  if [ "$DRY_RUN" -eq 1 ]; then
-    count=$(so_psql -c "SELECT count(*) FROM \"${qualified%.*}\".\"${qualified#*.}\" WHERE time < now() - interval '${DAYS} days';")
-    log "would delete ${count:-0} rows from ${qualified}"
-  else
-    # RETURNING count via a CTE so we can log how much was trimmed per table
-    deleted=$(so_psql -c "
-      WITH d AS (
-        DELETE FROM \"${qualified%.*}\".\"${qualified#*.}\"
-        WHERE time < now() - interval '${DAYS} days'
-        RETURNING 1
-      )
-      SELECT count(*) FROM d;")
-    deleted=${deleted:-0}
-    TOTAL_DELETED=$((TOTAL_DELETED + deleted))
-    [ "$deleted" -gt 0 ] && log "deleted ${deleted} rows from ${qualified}"
-  fi
-done
-
-if [ "$DRY_RUN" -eq 0 ]; then
-  log "Trim complete. Total rows deleted: ${TOTAL_DELETED}."
-fi