new: [vps] add ``recover-target`` action to recover files/directory from backup

Signed-off-by: Valentin Lab <valentin.lab@kalysto.org>

README.org

@@ -859,6 +859,29 @@ odoo:
 
 #+END_SRC
 
+** Récupération de donnée
+
+Via la commande =vps=, l'action =recover-target= permet de recouvrir
+les données du service d'archivage (si celui-ci à été correctement
+installé avec les commandes spécifiée dans la [[*rsync-backup][section =rsync-backup=]]).
+
+Récupération d'un répertoire:
+
+#+begin_src sh
+vps recover-target "cron/" /tmp/cron
+#+end_src
+
+Cette commande va récupérer le contenu archivé dans "cron/" pour le mettre
+sur l'hôte courant dans "/tmp/cron".
+
+Il est possible de spécifier l'option =--dry-run= (ou =-n=) pour ne
+rien modifier et voir quels sont les actions qui seront menées.
+
+Attention à l'usage de cette commande, en effet le répertoire de
+destination peut-être entièrement modifié : cette commande effacera et
+modifiera le contenu du répertoire de destination.
+
+
 ** Troubleshooting
 
 S'il semble qu'il y ait un soucis, tu peux visualiser le =docker-compose.yml= qui est

bin/vps

@@ -9,6 +9,7 @@ include cmdline
 include config
 include cache
 include fn
+include docker
 
 
 [[ "${BASH_SOURCE[0]}" != "${0}" ]] && SOURCED=true
@@ -106,6 +107,9 @@ type:is-compose() {
 
 
 vps:get-type() {
+
+    :cache: scope=session
+
     local fn
     for fn in $(declare -F | cut -f 3 -d " " | egrep "^type:is-"); do
         "$fn" && {
@@ -115,6 +119,7 @@ vps:get-type() {
     done
     return 1
 }
+decorator._mangle_fn vps:get-type
 
 
 mirror-dir:sources() {
@@ -307,7 +312,7 @@ compose:install-backup() {
         fi
     fi
 
-    ping_check "$DOMAIN" || return 1
+    ping_check "$host" || return 1
 
     if [ -e "/root/.ssh/rsync_rsa" ]; then
         warn "deleting private key in /root/.ssh/rsync_rsa, has we are not using it anymore."
@@ -368,6 +373,235 @@ EOF
 }
 
 
+backup-action() {
+    local action="$1"
+    shift
+    vps_type=$(vps:get-type) || {
+        err "Failed to get type of installation."
+        return 1
+    }
+    if ! fn.exists "${vps_type}:${action}"; then
+        err "type '${vps_type}' has no ${vps_type}:${action} implemented yet."
+        return 1
+    fi
+    "${vps_type}:${action}" "$@"
+}
+
+
+compose:get_default_backup_host_ident() {
+    local service_name="$1"  ## Optional
+    local compose_file service_cfg cfg target
+
+    compose_file=$(compose:get-compose-yml)
+    service_name="${service_name:-rsync-backup}"
+    if ! service_cfg=$(cat "$compose_file" |
+                           shyaml get-value -y "$service_name" 2>/dev/null); then
+        err "No service named '$service_name' found in 'compose.yml'."
+        return 1
+    fi
+    cfg=$(e "$service_cfg" | shyaml get-value -y options) || {
+        err "No ${WHITE}options${NORMAL} in ${DARKYELLOW}$service_name${NORMAL}'s" \
+            "entry in '$compose_file'."
+        return 1
+    }
+    if ! target=$(e "$cfg" | shyaml get-value target); then
+        err "No ${WHITE}options.target${NORMAL} in ${DARKYELLOW}$service_name${NORMAL}'s" \
+            "entry in '$compose_file'."
+    fi
+    if ! target=$(e "$cfg" | shyaml get-value target); then
+        err "No ${WHITE}options.target${NORMAL} in ${DARKYELLOW}$service_name${NORMAL}'s" \
+            "entry in '$compose_file'."
+    fi
+    if ! ident=$(e "$cfg" | shyaml get-value ident); then
+        err "No ${WHITE}options.ident${NORMAL} in ${DARKYELLOW}$service_name${NORMAL}'s" \
+            "entry in '$compose_file'."
+    fi
+    echo "$target $ident"
+}
+
+
+mailcow:get_default_backup_host_ident() {
+    local content cron_line ident found dest cmd_line
+    if ! [ -e "/etc/cron.d/mirror-dir" ]; then
+        err "No '/etc/cron.d/mirror-dir' found."
+        return 1
+    fi
+    content=$(cat /etc/cron.d/mirror-dir) || {
+        err "Can't read '/etc/cron.d/mirror-dir'."
+        return 1
+    }
+    if ! cron_line=$(e "$content" | grep "mirror-dir backup"); then
+        err "Can't find 'mirror-dir backup' line in  '/etc/cron.d/mirror-dir'."
+        return 1
+    fi
+
+    cron_line=${cron_line%|*}
+    cmd_line=(${cron_line#*root})
+
+    found=
+    dest=
+    for arg in "${cmd_line[@]}"; do
+        [ -n "$found" ] && {
+            dest="$arg"
+            break
+        }
+        [ "$arg" == "-d" ] && {
+            found=1
+        }
+    done
+
+    if ! [[ "$dest" =~ ^[\'\"a-zA-Z0-9:/.-]+$ ]]; then
+        err "Can't find valid destination in 'mirror-dir backup' arguments from '/etc/cron.d/mirror-dir'."
+        return 1
+    fi
+
+    if [[ "$dest" == \"*\" ]] || [[ "$dest" == \'*\' ]]; then
+        ## unquoting, the eval should be safe because of previous check
+        dest=$(eval e "$dest")
+    fi
+    if [ -z "$dest" ]; then
+        err "Can't find destination in 'mirror-dir backup' arguments from '/etc/cron.d/mirror-dir'."
+        return 1
+    fi
+
+    ## looking for ident
+
+    found=
+    ident=
+    for arg in "${cmd_line[@]}"; do
+        [ -n "$found" ] && {
+            ident="$arg"
+            break
+        }
+        [ "$arg" == "-h" ] && {
+            found=1
+        }
+    done
+
+    if ! [[ "$ident" =~ ^[\'\"a-zA-Z0-9.-]+$ ]]; then
+        err "Can't find valid identifier in 'mirror-dir backup' arguments from '/etc/cron.d/mirror-dir'."
+        return 1
+    fi
+
+    if [[ "$ident" == \"*\" ]] || [[ "$ident" == \'*\' ]]; then
+        ## unquoting, the eval should be safe because of previous check
+        ident=$(eval e "$ident")
+    fi
+    if [ -z "$ident" ]; then
+        err "Can't find destination in 'mirror-dir backup' arguments from '/etc/cron.d/mirror-dir'."
+        return 1
+    fi
+
+    echo "$dest $ident"
+}
+
+
+compose:get_cron_docker_cmd() {
+    local cron_line cmd_line docker_cmd
+    if ! cron_line=$(docker exec myc_cron_1 cat /etc/cron.d/rsync-backup | grep "\* \* \*"); then
+        err "Can't find cron_line in cron container."
+        echo "  Have you forgotten to run 'compose up' ?" >&2
+        return 1
+    fi
+
+    cron_line=${cron_line%|*}
+    cron_line=${cron_line%"2>&1"*}
+
+    cmd_line="${cron_line#*root}"
+    eval "args=($cmd_line)"
+
+    ## should be last argument
+
+    docker_cmd=$(echo ${args[@]: -1})
+
+    if ! [[ "$docker_cmd" == "docker run --rm -e "* ]]; then
+        echo "docker command found should start with 'docker run'." >&2
+        echo "Here's command:" >&2
+        echo "  $docker_cmd" >&2
+        return 1
+    fi
+
+    e "$docker_cmd"
+}
+
+
+compose:recover-target() {
+    local backup_host="$1" ident="$2" src="$3" dst="$4" service_name="${5:-rsync-backup}"
+
+    docker_image="myc_${service_name}"
+    if ! docker_has_image "$docker_image"; then
+        compose build "${service_name}" || {
+            err "Couldn't find nor build image for service '$service_name'."
+            return 1
+        }
+    fi
+
+    dst="${dst%/}"  ## remove final slash
+
+    ssh_options=(-o StrictHostKeyChecking=no)
+    if [[ "$backup_host" == *":"* ]]; then
+        port="${backup_host##*:}"
+        backup_host="${backup_host%%:*}"
+        ssh_options+=(-p "$port")
+    else
+        port=""
+        backup_host="${backup_host%%:*}"
+    fi
+
+    rsync_opts=(
+        -e "ssh ${ssh_options[*]} -i /var/lib/rsync/.ssh/id_rsa -l rsync"
+        -azvArH --delete --delete-excluded
+        --partial --partial-dir .rsync-partial
+        --numeric-ids
+    )
+    if [ "$DRY_RUN" ]; then
+        rsync_opts+=("-n")
+    fi
+    cmd=(
+    docker run --rm --entrypoint rsync \
+           -v "/srv/datastore/config/${service_name}/var/lib/rsync":/var/lib/rsync \
+           -v "${dst%/*}":/mnt/dest \
+           "$docker_image" \
+           "${rsync_opts[@]}" "$backup_host":"/var/mirror/$ident/$src" "/mnt/dest/${dst##*/}"
+    )
+    echo "${WHITE}Launching: ${NORMAL} ${cmd[@]}"
+    "${cmd[@]}"
+}
+
+
+mailcow:recover-target() {
+    local backup_host="$1" ident="$2" src="$3" dst="$4"
+
+    dst="${dst%/}"  ## remove final slash
+
+    ssh_options=(-o StrictHostKeyChecking=no)
+    if [[ "$backup_host" == *":"* ]]; then
+        port="${backup_host##*:}"
+        backup_host="${backup_host%%:*}"
+        ssh_options+=(-p "$port")
+    else
+        port=""
+        backup_host="${backup_host%%:*}"
+    fi
+
+    rsync_opts=(
+        -e "ssh ${ssh_options[*]} -i /var/lib/rsync/.ssh/id_rsa -l rsync"
+        -azvArH --delete --delete-excluded
+        --partial --partial-dir .rsync-partial
+        --numeric-ids
+    )
+    if [ "$DRY_RUN" ]; then
+        rsync_opts+=("-n")
+    fi
+    cmd=(
+        rsync "${rsync_opts[@]}" "$backup_host":"/var/mirror/$ident/$src" "${dst}"
+    )
+    echo "${WHITE}Launching: ${NORMAL} ${cmd[@]}"
+    "${cmd[@]}"
+}
+
+
+
 [ "$SOURCED" ] && return 0
 
 ##
@@ -553,29 +787,7 @@ set_errlvl() { return "${1:-1}"; }
 cmdline.spec:backup:cmd:compose:run() {
 
     local cron_line args
-    if ! cron_line=$(docker exec myc_cron_1 cat /etc/cron.d/rsync-backup | grep "\* \* \*"); then
-        err "Can't find cron_line in cron container."
-        echo "  Have you forgotten to run 'compose up' ?" >&2
-        exit 1
-    fi
-
-    cron_line=${cron_line%|*}
-    cron_line=${cron_line%"2>&1"*}
-
-    cmd_line="${cron_line#*root}"
-
-    eval "args=($cmd_line)"
-
-    ## should be last argument
-
-    docker_cmd=$(echo ${args[@]: -1})
-
-    if ! [[ "$docker_cmd" == "docker run --rm -e "* ]]; then
-        echo "docker command found should start with 'docker run'." >&2
-        echo "Here's command:" >&2
-        echo "  $docker_cmd" >&2
-        exit 1
-    fi
+    docker_cmd=$(compose:get_cron_docker_cmd) || return 1
 
     echo "${WHITE}Launching:${NORMAL} docker exec -i myc_cron_1 $docker_cmd"
 
@@ -595,4 +807,38 @@ cmdline.spec:backup:cmd:compose:run() {
 
 }
 
+
+cmdline.spec.gnu recover-target
+cmdline.spec::cmd:recover-target:run() {
+
+    : :posarg: BACKUP_DIR           'Source directory on backup side'
+    : :posarg: HOST_DIR             'Target directory on host side'
+
+    : :optval: --backup-host,-B     "The backup host"
+
+    : :optfla: --dry-run,-n         "Don't do anything, instead tell what it
+                                     would do."
+
+
+    ## if no backup host take the one by default
+    backup_host="$opt_backup_host"
+    if [ -z "$backup_host" ]; then
+        backup_host_ident=$(backup-action get_default_backup_host_ident) || return 1
+        read -r backup_host ident <<<"$backup_host_ident"
+    fi
+
+    if [[ "$BACKUP_DIR" == /* ]]; then
+        err "BACKUP_DIR must be a relative path from the root of your backup."
+        return 1
+    fi
+
+    REAL_HOST_DIR=$(realpath "$HOST_DIR") || {
+        err "Can't find HOST_DIR '$HOST_DIR'."
+        return 1
+    }
+    export DRY_RUN="${opt_dry_run}"
+    backup-action recover-target "$backup_host" "$ident" "$BACKUP_DIR" "$REAL_HOST_DIR"
+}
+
+
 cmdline::parse "$@"