Automate execution of workflow

[Ana914]

Hi all,

My inputs: Say I have multiple excel reader nodes (because they’re all in different formatting);
My output: Excel writer node

What I need is that the my workflow would produce a new output when/if my inputs (which are saved in one folder X) are

1. created or moved or saved in the folder X and
2. modified in folder X

I was wondering if anyone had this experience before and made it work and what did you do for your workflows to achieve it.

Please note I’m a newbie so explaining your answers like I’m 5 yo would really help

Thank you!

[iperez]

Hi @Ana914.!!
"Please note I’m a newbie so explaining your answers like I’m 5 yo would really help "

It is always nice to work with kids

The node Wait

does what you are asking for, you can parametrize it

such that that the downstream nodes of a workflow are not executed until there is a creation/Modification/deletion of a file event. Connect the variable port of the node to the first node you want to be executed when the event occurs.

Hope that helps

[Ana914]

Hey @iperez thanks for your reply.
I’m wondering if I can do both the criteria though for an excel reader node.

Because I could put a wait node and execute the workflows upon creation of a file. Yet I can’t connect it to another Wait node with the criteria “upon modification”?

[Ana914]

I also tried changing excel files in the folder with the wait node

but nothing seems to happen

[iperez]

Hi. What I would do is to create another workflow that calls the corresponding workflow to be run when either of the conditions are satisfied:

wait on create or modify.knwf (18.7 KB)

[mlauber71]

All this might be a good job for the KNIME server.

Having said that I created a small example where a system waits for a changing file and of the file has changed does something.

Start a Workflow, e. g. a database query, after a certain time

@USCHUKN1ME I tried to build a system you might be able to expand and use. The idea is to have a workflow that would iterate a number of times (v_number_of_intervals) with a set interval (of seconds) between (v_seconds_interval) them. The workflow looks for a trigger_file.csv if this file has changed from the last time the loop has run a component would be executed. If the file has not changed nothing would happen. Admittedly not the most elegant way but you could build a small automatic execu…

[Ana914]

Thanks but I still can’t justify the server’s cost so i was looking for a work around

[Ana914]

Thank you this would work

[USCHUKN1ME]

Same here !
12.500 € is too much , only for one workflow

[mlauber71]

I have suggested a workflow that would simulate an automation and would run an check for changes. Maybe you can adapt that.