A BASH script to run scripts/programs on a remote machine via Dropbox.

First you have to set up a folder within your Dropbox with the following structure:
Dropbox/remote/
Dropbox/remote/old/
Dropbox/remote/output/
Dropbox/remote/commands/

Optionally, the directory path can be specified as the initial argument, if a folder other than Dropbox/remote is desired.

Previous versions allowed you to specify a separate directory in the form of Dropbox/remote_{something} with {something} as the initial argument. I have preserved this, however this behavior is deprecated, and may be removed in future versions.

Place any executable files (scripts or compiled programs) into the commands folder.

Then run the following command to execute scripts on your machine:
dropbox_shell.sh
or dropbox_shell.sh {path}

All files in the commands folder will be executed. Output will be written to a log file in output, and the file will be moved to the old folder.

Certain special files (Java .jar, etc.) may be placed in the folder, and they will be executed by their respective interpreters/virtual machines.

Currently supported special files are:

• .class: run as java {classname}
• .jar: run as java -jar {file}
• .n: run as neko {file}

Additional special files can be supported by adding BASH functions to the script. The functions should be named like run_${mimetype}_${extension} where mimetype is the mime-type of the file (as determined by file -bi $file), with / being replaced with _, and all other non-alphabetic characters being removed. So, if the mime-type is application/octet-stream, and the file extension is .foobar, then the function definition would look something like this:

function run_application_octetstream_foobar()
{
    run_foobar "$1"
}

The file to be executed is passed as the sole argument to the function.

Feel free to send me your additional functions, and I may add them to the program.

If file is not available on the system, all files will be executed normally, so be sure to not use any special files on such a system.

In addition to special files, special folders can be defined from which a user-defined function will be run on all files within the folder. By default, the script supports a books folder, and a toprint folder. If any file is placed in the toprint folder, it will be sent as a print job to the default printer. This works for pdf, ps, gif, jpg, bmp, and tif files. If any file is placed in the books folder, it will be added to your calibre library. To add your own special folders, first create the folder, then add to the folder name to OTHERFOLDERS array, then create a function called run_folder_${foldername} where foldername is the name of the folder.

Other files will be made executable, and executed directly, so be sure to include a shebang in scripts.

If no files are found in commands or any of the special folders, the program does nothing.

Ideally, this should be added to a cronjob. My cronjob for this looks like this:
*/3 * * * * bash /path/to/dropbox_shell.sh
This runs it every three minutes.

If a file in the commands folder is named "at-some time string", instead of executing it right away, it's assumed to be a bash script to be run using the "at" command, and "some time string" is the time to execute it. E.g., creating a script in the folder called "at-now + 20 minutes" will cause that file to be run twenty minutes from the time dropbox_shell is run. This form should only be used for shell scripts.