It would be very nice to be able to run tableau prep flows from terminal or command prompt. This way, if you have multiple files to process and/or need to integrate with other tools/languages you can easily do so. For context, I came up with this idea when having to decide between writing a data sorting script in R (large time sink) that I could run from the terminal, or making a prep flow (less time to make) and having to download the files to run them in the flow and upload them back again each time.
I imagine tableau prep setting numbers to inputs and outputs in the tableau prep file. For example, if a flow has two inputs and 3 outputs, they would be labeled 1, 2, 3, 4, and 5 in an order that tableau prep decides. This way, if you want to run tableau prep from a terminal, you can pass file locations and output locations in that numbering order. Just like in python, when you run a piece of code, you might have
python filename.py "input file 1.csv" "input file 2.txt" "output location 1.txt"
tableau prep could do similarly. Say you want the second and third outputs, the command may look like
tableauprep filename.tfl "input file 1.csv" "input file 2.txt" "output location 2.txt" "output location 3.txt"
This would be very helpful for anyone that uses a terminal/command prompt and analyses data.
Possible issues may include interpreting data, especially from multi-tab excel sheets. this can be solved by only allowing simple file formats as inputs, aka comma separated and tab separated files. Choosing outputs is also not an issue, as shown with the example above.
It does not seem too difficult for tableau to implement this, as the numbering/indices would be a small amount of coding and the capability to choose output folders and filenames already exists. All that is needed to make this idea is an option to take an input from a file location rather than to have to add the sheet and then drag and drop the tab separately.