How to change data files of a deployed web app and maintain this change across sessions

I have a seployed web app which uses, internally, a number of Excel files, from where it reads some data. During runtime, I would like the user to be able to download one of those files, modify some data at wish and upload the modified file. The app should then be using that modified file instead of the initial one. Additionally, I want the modified file to persist across different runs of the app. Ideally, the modified file would be overwritting the initial file in the .ctf package.

Answer 1

[Walter Roberson]

The closest you can get is at run time figure out a suitable directory to check for files and to store into when the user makes changes.

You will have to decide whether the changes are to be available only to the one user or to all user on the same host or to all users of your application on all hosts.

[Chris Oreinos]

That was my initial feeling, but I was hoping for a more straightforward solution. My main concern about the proposed solution is that I cannot ensure that all app users will have access to any network location, since those permissions are tied to group policies.

[Walter Roberson]

Store them in a cloud ?

[Chris Oreinos]

That may work indeed. Now comes the question, is a web app able to open directly a file from a cloud? Otherwise the user would have to visit the cloud location on his own, modify and save the file. Is that right?

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/429699-writing-a-file-to-google-drive

In the most common uses, Google Drive and Microsoft One Drive mount like a network drive. However that assumes that the user is logged into that account. The above link does not assume login in that manner.

[Chris Oreinos]

I think Google Drive storage is out of the question due to company's security policies. However, saving to MS OneDrive is fine. Is there a way for MATLAB to read/write data from OneDrive? My search didn't result in any useful result.

[Walter Roberson]

Unfortunately I do not know much about OneDrive api. I do see

https://docs.microsoft.com/en-us/onedrive/developer/?view=odsp-graph-online

https://github.com/isac322/OneDrive-SDK-java

So it would be possible to connect to onedrive through an api such the Java api on github.