mcrbt/gather

Gather all self-written scripts from the file system

gather

Brief description

gather is a small Bash script for Linux operating systems intended to collect all self-written scripts from the file system. Therefore it needs to be able to distinguish between scripts that are shipped with a Linux distribution or have been installed later along with, or as part of, a software package for an official repository, and those written by the user, e.g. to automate tasks.

Preamble

When installing software on Linux the relevant files are distributed to specific file system locations. Executables may go to /usr/bin/, libraries may go to /usr/lib/, configuration files may go somewhere under /etc/, license documents, manual pages and other resources may go somewhere under /usr/share/, and so on. This is different from installing software on Windows or Mac operating systems where all the files are installed to one single directory, e.g. under C:\Program Files (x86)\ on Windows. In this case installed software searches for relevant files using paths relative to the executable.

Linux software is usually installed using a package manager, which moves files of the software to their respective locations. However, sometimes required software is not available in the official software repositories of a Linux distribution. Linux software downloaded from a website often comes as a "tar"-archive containing all required files. The user may use a specific file system location for software downloaded by a browser to be installed installed "the Windows way" (e.g. /usr/local/prg). The executable in that directory can then be symbolically linked from /usr/bin or /usr/local/bin. Executables of software written by the user is usually placed under /usr/local/bin (or symbolically linked from there, respectively).

Further remark

A better approach to the task gather tries to undertake may be to use the package manager of the respective Linux distribution to check whether a specific script is part of some package listed in the official (or even unofficial) repositories. That could potentially be a costly operation but would then be up to the package manager to perform it in reasonable time. The result could be more reliable (although not 100% correct). Anyway this would require the script to support numerous package managers and there are still new ones evolving. Hence that approach is not really reasonable in terms of this project.

Operation

gather scans the /usr/local/bin directory, following symbolic links. If an entry is a binary file (e.g. ELF 64-bit) that file is skipped. If a symbolic link points to a subdirectory of a "single directory installation location" (e.g. /usr/local/prg) this file is skipped, as well. All ASCII text files are evaluated using the "file" command, manually by inspecting the interpreter line at beginning of the file (e.g. #!/usr/bin/perl), or via its filename extension. All conforming files will be packed together as a tar archive, compressed with the xz tool and moved to a specified archiving location.

Configuration

The archive directory, as well as the root location for "single directory installations" can be configured by editing the variables at the beginning of the script gather.sh in the marked CONFIGURATION SECTION, namely ARLOC and SINGLE_INST_LOC.

Note: "Configuration" should be done before running the script to make it work properly.

gather.sh (or a symbolic link pointing to it) may reside under /usr/local/bin, as well. If it shall not be included in the resulting archive the "boolean" variable INCLUDE_GATHER can be altered. It can also be found in the CONFIGURATION SECTION at the beginning of the script, as well. A value of 0 means false (i.e. exclude gather from the archive), any other value means true (i.e. include gather in the archive).

Further configuration is not really intended, and should not be necessary. However, the script can be adapted to meet the users needs and use cases, of course.

Installation

In order to install gather only three simple steps are necessary.

1. Clone this repository to a local directory on your system, using:

$ git clone https://github.com/mcrbt/gather.git

2. Either move/copy the script gather.sh (with or without filename extension) to /usr/local/bin, or create a symbolic link in /usr/local/bin or $HOME/bin to gather.sh in the cloning/installation directory.

3. Make the script gather.sh (not the symbolic link) executable, using:

$ chmod 755 gather.sh

As /usr/local/bin is contained in the environment variable PATH by default, gather should then be accessible like any other command. If it shall reside in $HOME/bin that directory should be contained in the PATH variable, as well.

gather tests whether the user executing the script is root, where $HOME/bin would evaluate to /root/bin. To execute gather as non-privileged user the respective line (roughly line 258) in gather.sh can be removed or commented:

#if [ ! $EUID -eq 0 ]; then echo "please run as root"; exit 1; fi

Dependencies

As gather is a Bash script it naturally depends on the availability of various system tools. Almost all of these tools should be present on any Linux distribution by default. Here is the complete list of tools that must be installed for gather to work:

awk, basename, date, file, head, mkdir, mv, perl, readlink, sed, sort, tar, wc, xz

gather initially checks whether all the commands are installed on the system and are accessible via the PATH environment variable. The command which should also be in the list of dependencies, but as which is used to check for all the other dependencies that would be pointless, somehow.

Execution

Since gather has been moved/copied/symlinked to /usr/local/bin or $HOME/bin (which should be contained in your system PATH variable) it should simply be runnable via:

$ gather

or, in case the filename extension has not been stripped:

$ gather.sh

Command line interface

gather does not take any options regarding its behaviour. Still the following arguments are available:

gather [version | license | dependencies | help]

   version | -V | --version
      print version information

   license | -L | --license
      print GPLv3 license disclaimer

   dependencies | deps | -D | --deps | --dependencies
      print list of dependencies

   help | -h | --help | usage | -U | --usage
      print this usage information

Copyright

Copyright © 2020 Daniel Haase

gather is licensed under the GNU General Public License, version 3.

License disclaimer

gather - gather all self-written scripts
Copyright (C) 2020  Daniel Haase

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see
<https://www.gnu.org/licenses/gpl-3.0.txt>.

GPL (version 3)