Backup script - find file by pattern, read it's full name and pass to script - windows

Question

I'm trying to use 7-Zip for backup purposes.
I have already wrote script for full backup:
#echo off
set source="c:\Source"
set destination="C:\Dest"
set dd=%DATE:~0,2%
set mm=%DATE:~3,2%
set yyyy=%DATE:~6,4%
set curdate=%dd%-%mm%-%yyyy%
"C:\Program Files\7-Zip\7z.exe" a -tzip -ssw -mx6 -r0 %destination%\Full_%curdate%.zip %source%
The new script intended for incremental backup is started after the full backup is made. But I don't really get how to make my second script to read files from directory and look for the file staring like full_xx_xx_xxxx.zip and assign its filename to a variable and then pass it to the script for incremental backup.
I tried script below, but it's not working:
#echo off
set source="c:\Source"
set destination="c:\Dest"
set exten="Full_*.zip"
set passwd="NAS"
set dd=%DATE:~0,2%
set mm=%DATE:~3,2%
set yyyy=%DATE:~6,4%
set curdate=%dd%-%mm%-%yyyy%
for %%a in %exten do echo %%a
"C:\Program Files\7-Zip\7z.exe" u -tzip -ssw -r0 %destination%\%%a.zip -u- -up0q3x2z0!"%destination%\diff_%date%.zip" %source%

Answer 1

There are multiple mistakes in both scripts.
I recommend reading first How to set environment variables with spaces? and Why is no string output with 'echo %var%' after using 'set var = text' on command line?. The syntax set variable="value in quotes" is often not good because it assigns the string "value in quotes" with the double quotes and all trailing spaces/tabs which might exist also in batch file to the environment variable with name variable. This syntax is problematic on concatenating the string value of the environment variable with other strings as done in posted code with %destination% because of the " being now somewhere in middle of the final argument string instead of enclosing the entire argument string. Better is the syntax set "variable=value without or with spaces" with " left to variable name because of the double quotes are interpreted now as argument string separators and perhaps existing spaces/tabs on line after second " are ignored by Windows command processor.
The usage of dynamic environment variable DATE makes it possible to quickly get current locale date in a format usable for file/folder names. But it must be taken into account that the date format of value of DATE depends on region/country/locale set for the user account which is used on running the batch file. I suppose that echo %DATE% results in an output of a date in format DD.MM.YYYY and so the command lines using DATE are correct for you with your user account according to the configured country.
The FOR command line is completely wrong and results in an exit of batch file execution with an error message output by cmd.exe interpreting the batch file line by line. This error output can be seen on running the batch file from within a command prompt window instead of double clicking on the batch file. See debugging a batch file for details on how to debug a batch file to find syntax errors like this reported by Windows command processor during execution of a batch file.
So I suggest for the first batch file:
#echo off
set "Source=C:\Source"
set "Destination=C:\Dest"
set "CurrentDate=%DATE:~6,4%-%DATE:~3,2%-%DATE:~0,2%"
"%ProgramFiles%\7-Zip\7z.exe" a -tzip -ssw -mx6 -r0 "%Destination%\Full_%CurrentDate%.zip" "%Source%"
The current locale date is assigned to the environment variable CurrentDate in format YYYY-MM-DD instead of DD-MM-YYYY. The date format YYYY-MM-DD is the international date format according to ISO 8601. It has one big advantage in comparison to all locale date formats in file names: The file names with date in format YYYY-MM-DD sorted alphabetically as usual are at the same time sorted chronological. That makes it much easier for people and scripts finding a specific file in a list of file names with date in file name.
I am not really sure what you want to do with the second batch file. So I can only suppose what you want to do and suggest for the second batch file:
#echo off
set "Source=C:\Source"
set "Destination=C:\Dest"
set "CurrentDate=%DATE:~6,4%-%DATE:~3,2%-%DATE:~0,2%"
set "NamePattern=Full_*.zip"
for /F "skip=1 eol=| delims=" %%I in ('dir "%Destination%\%NamePattern%" /A-D /B /O-N 2^>nul') do (
"%ProgramFiles%\7-Zip\7z.exe" u -tzip -ssw -r0 "%Destination%\%%I" -u- -up0q3x2z0!"%Destination%\Diff_%CurrentDate%.zip" "%Source%"
goto Done
)
:Done
The FOR loop runs command DIR with using a separate command process started in background to get the list of Full_*.zip file names in destination directory sorted reverse by name which means the full backup ZIP file created today before with first batch file is at top on using date format YYYY-MM-DD and the previously created ZIP file from yesterday (or whenever the last but one full ZIP file was created) is output as second line.
FOR skips the first line with ZIP file name with current date and runs 7-Zip with previously created ZIP file (yesterday) to create the difference ZIP file. Then the FOR loop is exited without processing all other full ZIP files with a jump to the label below the FOR loop.
Both batch files together:
#echo off
setlocal EnableExtensions DisableDelayedExpansion
set "Source=C:\Source"
set "Destination=C:\Dest"
set "CurrentDate=%DATE:~6,4%-%DATE:~3,2%-%DATE:~0,2%"
set "NamePattern=Full_*.zip"
rem Create full ZIP backup.
"%ProgramFiles%\7-Zip\7z.exe" a -tzip -ssw -mx6 -r0 "%Destination%\Full_%CurrentDate%.zip" "%Source%"
rem Create difference ZIP backup with files added/changed in source directory
rem in comparison to the files compressed into last but on full ZIP backup.
for /F "skip=1 eol=| delims=" %%I in ('dir "%Destination%\%NamePattern%" /A-D /B /O-N 2^>nul') do (
"%ProgramFiles%\7-Zip\7z.exe" u -tzip -ssw -r0 "%Destination%\%%I" -u- -up0q3x2z0!"%Destination%\Diff_%CurrentDate%.zip" "%Source%"
goto Done
)
:Done
endlocal
For understanding the used commands and how they work, open a command prompt window, execute there the following commands, and read entirely all help pages displayed for each command very carefully.
dir /?
echo /?
endlocal /?
for /?
rem /?
set /?
setlocal /?