JuliaCall and Gurobi in a shinyapps.io website

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Hi all,

This is an exploratory question as I'm thinking about how to build out a shiny app - still in planning stages, so apologies if vague.

I'm building a dashboard that will need to execute some Julia code, using the JuliaCall package. Moreover, within Julia I will need to call Gurobi. My question is whether I would be able to host such a dashboard on shinyapps.io, Will rsconnect (or some other method, even ssh/command line) let me install the julia/gurobi distros that I need on the shinyapps server so that my dashboard can call them? I'm trying to avoid setting up/maintaining my own website and back-end shiny server but I'm guessing that might be the only option.

Thanks!

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Julia 1.0.2 is present in the shinyapps.io environment, so installing JuliaCall ought to work. Let us know if you find otherwise.

As for Gurobi, I don't know anything about that. In general you are able to write to the application's directory, so your code could install Gurobi local to itself. Alternatively, if there is an R package wrapper, you could open an issue or pull request per the documentation

Hope that helps!

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Gurobi does have an R package and its straightforward to use.

also, you should think about your infrastructure setup.
If you are using Julia and Gurobi, then you probably have some beefy computations running.
It might make more sense to separate the Shiny app and Julia/Gurobi portion into 2 separate services.
shinyapps.io is great but wouldn't be my pick to run a heavy computation or big optimization problem.
Gurobi also has a managed service.

2 Likes
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Were you able to build the app using JuliaCall? I'm currently building an app that uses Julia and although it runs locally I'm having issues when deploying. I'm wondering if you had success and, if so, how.

Thanks!

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I am bumping this.

Adding a mere JuliaCall::julia_call("println", "hello world!") results in a segfault. Could that be due to JuliaCall having to be synced with a certain Julia version? If so, would be great to have the currently supported range of JuliaCall (r package versions) documented somewhere.

edit: fixed quote typo

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is it a typo in your post only, or also in your code ? there are unbalanced quote marks

1 Like
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good catch, corrected it - wasn't the issue tho. JuliaCall documents this error

but I did not manage to fix it on shinyapps.io

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Hello

We just updated the version of Ubuntu used by shinyapps.io. Included in this is an update to the packages used by JuliaCall. This should correct the segfault you were experiencing.

thanks
sam