Enhance dovecot-logreport script: add progress display, improve sudo handling for unreadable log files, and update usage instructions

dovecot-logreport.sh

@@ -26,7 +26,7 @@ set -euo pipefail
 #       * --oneline: 1 Zeile TSV (kein Leerzeilentrenner)
 #       * --stats: Statistik statt Events (inkl. Matrix/Toplisten)
 #   - Live-Modus:
-#       * --follow: tail -F (gz-Dateien werden dafür übersprungen)
+#       * --follow: tail -F, sudo nur falls nötig (gz-Dateien werden dafür übersprungen)
 #
 # Anforderungen/Annahmen:
 #   - Timestamp steht als erstes Feld in ISO-Format (z.B. 2026-01-17T12:34:56+01:00)
@@ -53,6 +53,10 @@ FOLLOW=0
 ALL=0
 ONELINE=0
 STATS=0
+SHOW_PROGRESS=0
+if [[ -t 2 ]]; then
+  SHOW_PROGRESS=1
+fi
 
 # Service-/Event-Filter (OR-verknüpft, wenn mehrere gesetzt sind)
 ONLY_LOGIN=0
@@ -111,7 +115,7 @@ INPUT OPTIONS
         You can combine --all and --file to add extra files.
 
   --follow
-      Follow the active logfile(s) (tail -F).
+      Follow the active logfile(s) (tail -F; sudo only if needed).
       .gz files cannot be followed and will be skipped in follow mode.
 
 TIME FILTERS (ISO8601 recommended)
@@ -336,6 +340,24 @@ if [[ $FOLLOW -eq 1 ]]; then
   [[ ${#FOLLOW_FILES[@]} -gt 0 ]] || die "--follow requested, but only .gz files selected. Add an active log with --file."
 fi
 
+NEED_SUDO=0
+declare -a UNREADABLE_FILES=()
+for f in "${LOGFILES[@]}"; do
+  if ! { : < "$f"; } 2>/dev/null; then
+    NEED_SUDO=1
+    UNREADABLE_FILES+=("$f")
+  fi
+done
+
+if [[ $NEED_SUDO -eq 1 ]]; then
+  {
+    echo "Using sudo because these selected log file(s) cannot be opened for reading by $(id -un):"
+    echo "Current groups: $(id -nG)"
+    printf "  %s\n" "${UNREADABLE_FILES[@]}"
+  } >&2
+  sudo -v || die "sudo authentication failed; cannot read Dovecot log files."
+fi
+
 # -------------------------------------------------------------------
 # POSIX-AWK Parser
 #   - kompatibel zu mawk/nawk/busybox awk
@@ -388,7 +410,7 @@ function extract_type(line, arr, t) {
 #   Tries to extract a user/mailbox from common patterns.
 function extract_user(line, arr, u) {
   if (match(line, /user=<[^>]+>/, arr)) {
-    return substr(arr[0], 7, length(arr[0])-7-1)
+    return substr(arr[0], 7, length(arr[0])-7)
   }
 
   if (match(line, /: (imap|pop3|lmtp)\([^)]*\)/, arr)) {
@@ -468,42 +490,49 @@ function type_regex_match(type, typere) {
   return 0
 }
 
-# ---- STATS helper: sort and print top N ----
+# ---- progress spinner on stderr ----
-function print_top_sorted(title, arr, n,   k,i,j,keys,tmp) {
+function progress_tick(   now, ch) {
+  if (show_progress != 1) return
+
+  now = systime()
+  if (PROGRESS_LAST != "" && now - PROGRESS_LAST < 2) return
+
+  PROGRESS_LAST = now
+  PROGRESS_IDX = (PROGRESS_IDX % 4) + 1
+  ch = substr("|/-\\", PROGRESS_IDX, 1)
+  printf "\r%s", ch > "/dev/stderr"
+  fflush("/dev/stderr")
+  PROGRESS_DRAWN = 1
+}
+
+function progress_clear() {
+  if (show_progress != 1 || PROGRESS_DRAWN != 1) return
+  printf "\r \r" > "/dev/stderr"
+  fflush("/dev/stderr")
+  PROGRESS_DRAWN = 0
+}
+
+# ---- STATS helper: keep only Top N while scanning the array ----
+function print_top_sorted(title, arr, n,   k,i,pos,count,topk,topv) {
   print title
-  i=0
-  for (k in arr) { i++; keys[i]=k }
 
-  for (i=1; i<=length(keys); i++) {
+  count=0
-    for (j=i+1; j<=length(keys); j++) {
+  for (k in arr) {
-      if (arr[keys[j]] > arr[keys[i]]) {
+    pos=1
-        tmp=keys[i]; keys[i]=keys[j]; keys[j]=tmp
+    while (pos<=count && arr[k] <= topv[pos]) pos++
-      }
+    if (pos > n) continue
+
+    if (count < n) count++
+    for (i=count; i>pos; i--) {
+      topk[i]=topk[i-1]
+      topv[i]=topv[i-1]
     }
+    topk[pos]=k
+    topv[pos]=arr[k]
   }
 
-  for (i=1; i<=length(keys) && i<=n; i++) {
+  for (i=1; i<=count; i++) {
-    printf "  %7d  %s\n", arr[keys[i]], keys[i]
+    printf "  %7d  %s\n", topv[i], topk[i]
-  }
-  print ""
-}
-
-# ---- STATS helper: sort and print top N for matrix-like keys ----
-function print_matrix(title, arr, n,   k,i,j,keys,tmp) {
-  print title
-  i=0
-  for (k in arr) { i++; keys[i]=k }
-
-  for (i=1; i<=length(keys); i++) {
-    for (j=i+1; j<=length(keys); j++) {
-      if (arr[keys[j]] > arr[keys[i]]) {
-        tmp=keys[i]; keys[i]=keys[j]; keys[j]=tmp
-      }
-    }
-  }
-
-  for (i=1; i<=length(keys) && i<=n; i++) {
-    printf "  %7d  %s\n", arr[keys[i]], keys[i]
   }
   print ""
 }
@@ -524,10 +553,14 @@ BEGIN {
   onlypop3  = ENVIRON["ONLY_POP3"] + 0
 
   typere = ENVIRON["TYPE_RE"]
+  show_progress = ENVIRON["SHOW_PROGRESS"] + 0
   total=0
+  progress_tick()
 }
 
 {
+  progress_tick()
+
   line=$0
   if (line !~ /dovecot:/) next
 
@@ -592,10 +625,12 @@ BEGIN {
 
   # Eventausgabe
   if (oneline == 1) {
+    progress_clear()
     printf "%s\t%s\t%s\t%s\t%s\t%s\n", ts, type, res, ip, user, msg
     next
   }
 
+  progress_clear()
   print "time:      " ts
   print "type:      " type
   print "client-ip: " ip
@@ -606,6 +641,7 @@ BEGIN {
 }
 
 END {
+  progress_clear()
   if (stats != 1) exit
 
   print "Events: " total
@@ -626,7 +662,7 @@ END {
   print_top_sorted("Top users (overall, Top 10)", c_user, 10)
   print_top_sorted("Top users (fail only, Top 10)", c_user_fail, 10)
 
-  print_matrix("Matrix result@type (Top 30)", c_res_type, 30)
+  print_top_sorted("Matrix result@type (Top 30)", c_res_type, 30)
 
   print_top_sorted("Fail combos IP -> user (Top 20)", c_fail_ip_user, 20)
 }
@@ -635,16 +671,25 @@ END {
 # -------------------------------------------------------------------
 # run_pipeline():
 #   Liest die ausgewählten Files (inkl. .gz über zcat -f) und pipe't
-#   in awk. In --follow Mode: tail -F auf nicht-gz Dateien.
+#   in awk. sudo wird nur verwendet, wenn mindestens eine Logdatei nicht
+#   direkt lesbar ist. In --follow Mode: tail -F auf nicht-gz Dateien.
 # -------------------------------------------------------------------
+run_read() {
+  if [[ $NEED_SUDO -eq 1 ]]; then
+    sudo "$@"
+  else
+    "$@"
+  fi
+}
+
 run_pipeline() {
   local f
 
   if [[ $FOLLOW -eq 1 ]]; then
-    tail -F "${FOLLOW_FILES[@]}" | \
+    run_read tail -F "${FOLLOW_FILES[@]}" | \
       env SINCE="$SINCE" UNTIL="$UNTIL" ADDR_RE="$ADDR_RE" EMAIL_NEEDLE="$EMAIL_NEEDLE" TYPE_RE="$TYPE_RE" \
           ONLY_LOGIN="$ONLY_LOGIN" ONLY_LMTP="$ONLY_LMTP" ONLY_IMAP="$ONLY_IMAP" ONLY_POP3="$ONLY_POP3" \
-          STATUS_FILTER="$STATUS_FILTER" ONELINE="$ONELINE" STATS="$STATS" \
+          STATUS_FILTER="$STATUS_FILTER" ONELINE="$ONELINE" STATS="$STATS" SHOW_PROGRESS="$SHOW_PROGRESS" \
       awk "$AWK_SCRIPT"
     return
   fi
@@ -652,16 +697,15 @@ run_pipeline() {
   {
     for f in "${LOGFILES[@]}"; do
       if [[ "$f" =~ \.gz$ ]]; then
-        zcat -f -- "$f" 2>/dev/null || true
+        run_read zcat -f -- "$f" || true
       else
-        cat -- "$f" 2>/dev/null || true
+        run_read cat -- "$f" || true
       fi
     done
   } | env SINCE="$SINCE" UNTIL="$UNTIL" ADDR_RE="$ADDR_RE" EMAIL_NEEDLE="$EMAIL_NEEDLE" TYPE_RE="$TYPE_RE" \
           ONLY_LOGIN="$ONLY_LOGIN" ONLY_LMTP="$ONLY_LMTP" ONLY_IMAP="$ONLY_IMAP" ONLY_POP3="$ONLY_POP3" \
-          STATUS_FILTER="$STATUS_FILTER" ONELINE="$ONELINE" STATS="$STATS" \
+          STATUS_FILTER="$STATUS_FILTER" ONELINE="$ONELINE" STATS="$STATS" SHOW_PROGRESS="$SHOW_PROGRESS" \
       awk "$AWK_SCRIPT"
 }
 
 run_pipeline
-