I am relatively new to KNIME and therefore ask you for help in this.
I do want to change the path of every writer/reader node (in my case all excel) based on the user who is executing the workflow.
The path is mostly similar only the first part needs to be changed. (e.g. C:\Users\Thomas\OneDrive\General.…) only the bold part needs to be changed.
I found a way in another thread using variable expressions and joining every single path. However this would result in me having to define every single path upfront. In ideal case I would like define the path still trough browsing via the reader/writer node and having a component where I define the first part of the path as path variable.
Does anyone know if there is such a solution?
Hi Thomas,
Welcome to the KNIME Forum! Generally, for such dynamic paths the Create File/Folder Variables node is really helpful, but as you mentioned, you can also use a variable expression. But if you let the user browse and then you want to adapt the path, how would the workflow find out which part of the path is dynamic? You could let the user select a path at the beginning of the workflow and then dynamically append to that. Is that what you need? In that case you can use the Create File/Folder Variables and control the base folder using a flow variable which gets its value from the folder selected by the user. Does that make sense?
Kind regards,
Alexander
If you are working with a company shared drive, like we also do, I can recommend using the Extract System Properties node and build your path dynamically accordingly in a component.
With this, we only have to fill in the path to a file once and the component takes care of the rest automatically.
In general, it works like this:
In the component dialoag, specify the file location.
In the component, extract the user.home with Extract System Properties.
Convert this to a flow variable and connect it to either a String Manipulation or Column Expression node
To get the filepath with the dynamic user.home you can use: variable("user.home") + "\\" + regexReplace(variable("filepath_input"), ".+?(?=OneDrive)", "")
So even though you have filled C:\Users\Thomas, it now changed to my user. Convert this string to Path to use in the writers and ouput this new flow variable accordingly.
Connect it to the writer node and make the file location flow variable controlled.
