keep track of rebalances in a 'database' file

README.md

@@ -11,7 +11,18 @@ Note that this process is not entirely "in-place", since a file has to be fully
 
 At no point in time are both versions of the original file deleted.
 To make sure file attributes, permissions and file content are maintained when copying the original file, all attributes and the file checksum is compared before removing the original file.
-Since file attributes are fully retained, it is not possible to verify if an individual file has been rebalanced.
+
+Since file attributes are fully retained, it is not possible to verify if an individual file has been rebalanced. However, this script keeps track of rebalanced files by maintaining a "database" file called `rebalance_db.txt` in its working directory. This file contains two lines of text for each processed file:
+
+* One line for the file path
+* and the next line for the current count of rebalances
+
+```text
+/my/example/pool/file1.mkv
+1
+/my/example/pool/file2.mkv
+1
+```
 
 ## Prerequisites
 

rebalance_db.txt

@@ -0,0 +1,20 @@
+/home/markus/music/Vorsingen 21.02.2020/080101-000.wav
+1
+/home/markus/music/Vorsingen 21.02.2020/Der Vogelfänger - Can.mp3
+1
+/home/markus/music/Vorsingen 21.02.2020/Bona Nox - Chor.mp3
+1
+/home/markus/music/Vorsingen 21.02.2020/Gambenkanon - Chor.mp3
+1
+/home/markus/music/Vorsingen 21.02.2020/Großer Herr - Can.mp3
+1
+/home/markus/music/Vorsingen 21.02.2020/Arie des Harlekin - Bruno.mp3
+1
+/home/markus/music/190904-004.wav
+1
+/home/markus/music/190904-002.wav
+1
+/home/markus/music/190904-003.wav
+1
+/home/markus/music/190904-002_edited.mp3
+1

zfs-inplace-rebalancing.sh

@@ -5,6 +5,9 @@ set -e
 # exit on undeclared variable
 set -u
 
+# file used to track processed files
+rebalance_db_file_name="rebalance_db.txt"
+
 # index used for progress
 current_index=0
 
@@ -118,6 +121,20 @@ function rebalance () {
 
     echo "Renaming temporary copy to original '${file_path}'..."
     mv "${tmp_file_path}" "${file_path}"
+
+    # update rebalance "database"
+    touch "./${rebalance_db_file_name}"
+    line_nr=$(grep -n "${file_path}" "./${rebalance_db_file_name}" | head -n 1 | cut -d: -f1)
+    if [ -z ${line_nr} ]; then
+      rebalance_count=1
+      echo "${file_path}" >> "./${rebalance_db_file_name}"
+      echo "${rebalance_count}" >> "./${rebalance_db_file_name}"
+    else
+      rebalance_count_line_nr="$((line_nr + 1))"
+      rebalance_count=$(awk "NR == ${rebalance_count_line_nr}" "./${rebalance_db_file_name}")
+      rebalance_count="$((rebalance_count + 1))"
+      sed -i "${rebalance_count_line_nr}s/.*/${rebalance_count}/" "./${rebalance_db_file_name}"
+    fi
 }
 
 root_path=$1