[rc-1.6.0] Installer: a rerun keeps the web backup of the release it upgraded from

bin/revertfog.sh

@@ -291,9 +291,11 @@ _candidateDumps() {
 # ---------------------------------------------------------------------------
 # Same problem as the dump and the same answer. configureHttpd() REMOVES an
 # existing fog_web_<ver>.BACKUP before writing a new one, so a second
-# installfog.sh run after a failed upgrade overwrites the 1.5 tree with the
-# 1.6 one it just laid down -- and the directory name, which carries the
-# version being installed, looks identical either way.
+# installfog.sh run after a failed upgrade used to overwrite the 1.5 tree with
+# the 1.6 one it just laid down -- and the directory name, which carries the
+# version being installed, looks identical either way. The installer now
+# renames a backup of another release after its own version first (GH-2000),
+# but a server upgraded before that change may still hold only the 1.6 copy.
 #
 # 1.5 keeps its classes under lib/fog/ and has no src/; 1.6 is PSR-4 under
 # src/ (ADR 0013) and has no lib/fog/. One file each way settles it.

docs/release/1.6.0-release-notes.md

@@ -117,16 +117,19 @@ persisted to .fogsettings (lib/common/functions.sh:6539). -->
 - **Web tree:** `${DB_backup_path}/fog_web_<version>.BACKUP`
   <!-- verified: lib/common/functions.sh:10483-10499. -->
 
-Both are named after the version being upgraded *from*, not the one you're
-upgrading to. Check `${DB_backup_path}` (default `/home/`, or whatever you
+Both are named after the version being *installed*, not the one you are
+upgrading from. The dump also carries a timestamp, so every run keeps its own.
+If you run the installer a second time, the web backup from the first run holds
+your 1.5 tree. The second run renames it after its own version
+(`fog_web_<1.5 version>.BACKUP`) instead of replacing it. Check `${DB_backup_path}` (default `/home/`, or whatever you
 passed to `-B` / recorded in `.fogsettings`) after the upgrade to confirm
 both exist before you consider the run safe to walk away from.
 
 ### 3. If something goes wrong: reverting
 
 `bin/revertfog.sh` restores a FOG install from the backups above. It must be
-run as root, from the `bin/` directory of a **1.5** checkout — the one you
-are going back to:
+run as root, from the `bin/` directory of the **1.6** checkout you upgraded
+with. A 1.5 checkout does not contain it:
 
 ```
 Usage: ./revertfog.sh [-h?y] [--list] [--dump <path>] [--kernel-generation <N>] [--dry-run]

lib/common/functions.sh

@@ -12840,6 +12840,34 @@ _warnUnrecognizedPlugins() {
     echo "  and re-run, or install them from that directory via the UI."
     echo
 }
+# Keep a web backup that holds a DIFFERENT release, instead of deleting it.
+#
+# The backup is named after the version being installed, and configureHttpd()
+# removes any existing one of that name before copying the current tree in. On
+# the first 1.5 -> 1.6 run that directory holds the 1.5 tree. A second run of
+# the same release then finds the 1.6 tree it laid down, and replacing the
+# backup deleted the only copy of 1.5 -- the tree bin/revertfog.sh needs
+# (GH-2000).
+#
+# So a backup whose own FOG_VERSION is not $version is renamed after its own
+# version, with a timestamp if that name is taken. bin/revertfog.sh finds it by
+# its fog_web_*.BACKUP glob. A backup of the same release is still replaced,
+# exactly as before. The files are the version file of each layout: the
+# generated 1.6 one, its tracked fallback, and 1.5's lib/fog/.
+_setAsideOtherVersionWebBackup() {
+    local backup="${DB_backup_path}/fog_web_${version}.BACKUP"
+    [[ -d $backup ]] || return 0
+    local f="" held=""
+    for f in commons/version.php src/Base/System.php lib/fog/system.class.php; do
+        [[ -f $backup/$f ]] || continue
+        held="$(awk -F\' /"define\('FOG_VERSION'[,](.*)"/'{print $4}' "$backup/$f" | tr -d '[[:space:]]')"
+        [[ -n $held ]] && break
+    done
+    [[ -z $held || $held == "$version" ]] && return 0
+    local dest="${DB_backup_path}/fog_web_${held}.BACKUP"
+    [[ -e $dest ]] && dest="${DB_backup_path}/fog_web_${held}_$(date +%Y%m%d_%H%M%S).BACKUP"
+    mv "$backup" "$dest" >>$error_log 2>&1
+}
 configureHttpd() {
     normalizeWebroot
     # Both customizations trees, before anything below needs either of them.
@@ -13002,6 +13030,7 @@ configureHttpd() {
     # the time that runs the evidence has been deleted. The list itself is
     # $retiredplugins, defined at the top level beside those two functions.
     retiredpluginsstripped=""
+    _setAsideOtherVersionWebBackup
     if [[ -d ${DB_backup_path}/fog_web_${version}.BACKUP ]]; then
         rm -rf ${DB_backup_path}/fog_web_${version}.BACKUP >>$error_log 2>&1
     fi

tests/web-backup-keeps-other-release.test.sh

@@ -0,0 +1,114 @@
+#!/bin/bash
+#
+# A second install run keeps the web backup of the release it upgraded from.
+#
+#   tests/web-backup-keeps-other-release.test.sh
+#
+# configureHttpd() names the web backup fog_web_${version}.BACKUP, after the
+# version being INSTALLED, and removes any existing one before it copies the
+# current tree in. A 1.5 -> 1.6 upgrade that is run twice therefore replaced the
+# 1.5 tree with the 1.6 one, and bin/revertfog.sh had no web tree left to
+# restore (GH-2000). _setAsideOtherVersionWebBackup() renames a backup of a
+# different release out of the way instead.
+#
+# The function is EXECUTED against fixtures, not read.
+#
+# No root, no network, no FOG install.
+#
+# Usage: bash tests/web-backup-keeps-other-release.test.sh
+# Exit status 0 = pass, 1 = fail.
+
+root=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)
+functions="$root/lib/common/functions.sh"
+
+pass=0
+fail=0
+
+check() {
+    if [[ $2 -eq 0 ]]; then
+        pass=$((pass + 1))
+    else
+        fail=$((fail + 1))
+        printf '  FAIL  %s\n' "$1"
+    fi
+}
+
+snippet=$(awk '
+    /^_setAsideOtherVersionWebBackup\(\) \{/ { grab = 1 }
+    grab { print }
+    grab && /^\}$/ { exit }
+' "$functions")
+if [[ -z $snippet ]]; then
+    echo "FAIL: could not find _setAsideOtherVersionWebBackup in lib/common/functions.sh" >&2
+    exit 1
+fi
+eval "$snippet"
+
+# The backup step must call it before it removes the old backup.
+grep -Pzo '_setAsideOtherVersionWebBackup\n    if \[\[ -d \$\{DB_backup_path\}/fog_web_\$\{version\}\.BACKUP \]\]; then\n        rm -rf' "$functions" >/dev/null
+check "configureHttpd() calls it before removing fog_web_\${version}.BACKUP" $?
+
+work=$(mktemp -d)
+trap 'rm -rf "$work"' EXIT
+error_log="$work/error.log"
+version="1.6.0-RC-19"
+
+# Write a backup holding release $2 in the layout $3 (15, 16, 16fallback).
+mkbackup() {
+    local dir="$DB_backup_path/$1"
+    case $3 in
+        15) mkdir -p "$dir/lib/fog"; printf "define('FOG_VERSION', '%s');\n" "$2" > "$dir/lib/fog/system.class.php" ;;
+        16) mkdir -p "$dir/commons" "$dir/src/Base"
+            printf "define('FOG_VERSION', '%s');\n" "$2" > "$dir/commons/version.php"
+            printf "define('FOG_VERSION', 'fallback');\n" > "$dir/src/Base/System.php" ;;
+        16fallback) mkdir -p "$dir/src/Base"; printf "define('FOG_VERSION', '%s');\n" "$2" > "$dir/src/Base/System.php" ;;
+    esac
+    touch "$dir/marker-$2"
+}
+reset() { rm -rf "$work/backup"; DB_backup_path="$work/backup"; mkdir -p "$DB_backup_path"; }
+
+# --- the GH-2000 rerun: the backup holds 1.5 ---------------------------------
+reset
+mkbackup "fog_web_${version}.BACKUP" "1.5.10.2518" 15
+_setAsideOtherVersionWebBackup
+[[ ! -e $DB_backup_path/fog_web_${version}.BACKUP ]]
+check "a 1.5 tree under the 1.6 name is moved off that name" $?
+[[ -f $DB_backup_path/fog_web_1.5.10.2518.BACKUP/marker-1.5.10.2518 ]]
+check "and kept, renamed after its own version" $?
+
+# --- that name is already taken: keep both -----------------------------------
+reset
+mkbackup "fog_web_1.5.10.2518.BACKUP" "1.5.10.2518" 15
+mkbackup "fog_web_${version}.BACKUP" "1.5.10.2518" 15
+_setAsideOtherVersionWebBackup
+n=$(find "$DB_backup_path" -maxdepth 1 -name 'fog_web_1.5.10.2518_*.BACKUP' | wc -l)
+[[ $n -eq 1 && -d $DB_backup_path/fog_web_1.5.10.2518.BACKUP ]]
+check "an existing backup of that release is not overwritten" $?
+
+# --- an older 1.6 build, read from the generated version file ----------------
+reset
+mkbackup "fog_web_${version}.BACKUP" "1.6.0-RC-18" 16
+_setAsideOtherVersionWebBackup
+[[ -d $DB_backup_path/fog_web_1.6.0-RC-18.BACKUP && ! -e $DB_backup_path/fog_web_${version}.BACKUP ]]
+check "a 1.6 tree's generated version.php wins over the fallback" $?
+
+# --- the same release: left for the caller to replace, as before -------------
+reset
+mkbackup "fog_web_${version}.BACKUP" "$version" 16fallback
+_setAsideOtherVersionWebBackup
+[[ -f $DB_backup_path/fog_web_${version}.BACKUP/marker-$version ]]
+check "a backup of the release being installed stays where it is" $?
+[[ $(find "$DB_backup_path" -mindepth 1 -maxdepth 1 | wc -l) -eq 1 ]]
+check "and nothing else is created" $?
+
+# --- no backup, or one with no readable version ------------------------------
+reset
+_setAsideOtherVersionWebBackup
+check "no backup: returns 0" $?
+mkdir -p "$DB_backup_path/fog_web_${version}.BACKUP"
+_setAsideOtherVersionWebBackup
+[[ -d $DB_backup_path/fog_web_${version}.BACKUP ]]
+check "an unreadable version leaves the backup to the old path" $?
+
+echo "web backup keeps other release: $pass passed, $fail failed"
+[[ $fail -eq 0 ]]