From dcffa9ab5e6f696542df9e0c909e62c4935734e2 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Felix=20D=C3=B6rre?= <felix@dogcraft.de>
Date: Thu, 30 Nov 2017 21:10:24 +0100
Subject: [PATCH] add: archiving of container-journals

Change-Id: Ifa920794c3b4dbc7cc619f5d6570b5d82505f200
---
 backup         | 18 ++++++++++++++
 manager/backup | 64 +++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 81 insertions(+), 1 deletion(-)

diff --git a/backup b/backup
index e1be93e..79e7478 100755
--- a/backup
+++ b/backup
@@ -103,6 +103,24 @@ EOF
         mkdir -p "/data/postgres/conf/${postgres_cluster}"
         printf "auto\n" > "/data/postgres/conf/${postgres_cluster}/start.conf"
         touch "/data/postgres/conf/${postgres_cluster}/postgresql.conf"
+    elif [[ $command == journal ]]; then
+        read -e from
+        action=$(date -u -d '00:00 today' +%s)
+        if [[ $action == $from ]]; then
+            printf "no journals\n"
+            continue
+        fi
+        printf "Until: %s\n" "$action"
+        for i in $(sudo lxc-ls); do
+            [[ $i == "base-image" ]] && continue
+            printf "journal: %s\n" "$i"
+            if [[ $from == - ]]; then
+                lxc-attach -n "$i" -- journalctl --utc --until="@$action" -o export | chunked
+            else
+                lxc-attach -n "$i" -- journalctl --utc --since="@$from" --until="@$action" -o export | chunked
+            fi
+        done
+        printf "end-of-journals\n"
     elif [[ $command == end ]]; then
         printf "end\n"
     fi
diff --git a/manager/backup b/manager/backup
index 22d536c..b707952 100755
--- a/manager/backup
+++ b/manager/backup
@@ -1,5 +1,4 @@
 #!/bin/bash
-
 targetHost=$1
 targetHost=${targetHost%/}
 source config
@@ -82,6 +81,64 @@ function incremental {
     printf "Done incremental backup\n"
 }
 
+# This code snippet cannot be used inline and therefore has to be a function.
+# When calling this function like 'receive_journal "journal" <&$fd', the
+# file-descriptor "$fd" is resolved in the calling original shell.
+# However when inlining this code like "... | ... <&$fd" the file-descriptor
+# is resolved in the first subshell created by this command and therefore
+# not valid anymore.
+function receive_journal {
+    chunked decode | /lib/systemd/systemd-journal-remote -o "$1" -
+}
+function journal {
+    printf "Fetching journals...\n"
+    printf "journal\n" >&${COPROC[1]}
+    folder="$self"
+    for i in {1..10}; do
+        folder="$folder/prev"
+        if [[ -f "$folder/journal-until" ]]; then
+            break;
+        fi
+    done
+    if [[ -f "$folder/journal-until" ]]; then
+        printf "From: "
+        from="$(cat "$folder/journal-until")"
+        date --utc -d "@$from"
+        printf -- "%s\n" "$from" >&${COPROC[1]}
+    else
+        printf "From: start\n"
+        printf -- "-\n" >&${COPROC[1]}
+    fi
+    read -r until <&${COPROC[0]} || exit 1;
+    if [[ $until == "no journals" ]]; then
+        printf "no journal events\n"
+        return 1
+    fi
+    if [[ ! $until == "Until: "* ]]; then
+        printf "Unexpected Until line: %s\n" "$until"
+        exit 1
+    fi
+    until="${until#Until: }"
+    printf "until: "
+    date --utc -d "@$until"
+
+    printf "Until: %s\n" "$until"
+    while :; do
+        read -r line <&${COPROC[0]} || exit 1;
+        if [[ $line == "end-of-journals" ]]; then
+            break;
+        fi
+        jnl="${line#journal: }"
+        printf "journal: %s\n" "$jnl"
+        receive_journal "$self/part-$jnl.journal" <&${COPROC[0]}
+    done
+    journalctl --file="$self/part-*" -o export | /lib/systemd/systemd-journal-remote -o "$self/all.journal" -
+    printf "Removing split journals:\n"
+    rm -v "$self/part-"*.journal
+    cat > "$self/journal-until" <<< "$until"
+    ls -als "$self"
+}
+
 if [[ "$2" == "restore" ]]; then
     sourceHost=$3
     sourceHost=${sourceHost%/}
@@ -126,8 +183,13 @@ if [[ "$2" == "restore" ]]; then
     fi
     printf "n\n" >&${COPROC[1]}
 elif [[ "$2" == "backup" ]]; then
+    if ! [[ -x /lib/systemd/systemd-journal-remote ]]; then
+        printf "This script requires 'systemd-journal-remote' to reformat received journals\n"
+        exit 1
+    fi
     start_backup
     incremental
+    journal
 else
     printf "Error, unknown sub command: %s\n" "$2" >&2
 fi
-- 
2.39.2