Shiny app running in rstudio-server doesn't work

[Lorena_Ferreira]

Hello everyone,

I am having a very strange problem. I have a shiny app running in a rstudio-server at my office. When I run the app from my notebook with a VPN connection it works fine, but when I get the app running from my PC in the office I get the UI visualization ok, but I do not get the server response. The first code lines that I have in the server is to open 3 shp files and when I run the app from my PC in the office nothing happens.

This is my sessionInfo ():

R version 3.6.3 (2020-02-29)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 20.04.4 LTS

Matrix products: default
BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.9.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.9.0

locale:
[1] LC_CTYPE=es_AR.UTF-8 LC_NUMERIC=C LC_TIME=es_AR.UTF-8 LC_COLLATE=es_AR.UTF-8 LC_MONETARY=es_AR.UTF-8 LC_MESSAGES=es_AR.UTF-8
[7] LC_PAPER=es_AR.UTF-8 LC_NAME=C LC_ADDRESS=C LC_TELEPHONE=C LC_MEASUREMENT=es_AR.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] waiter_0.2.5 fields_13.3 spam_2.8-0 raster_3.5-15 rgdal_1.5-32 sp_1.4-6 shinydashboard_0.7.2 shinyWidgets_0.7.0
[9] shiny_1.7.1 magrittr_2.0.3 viridis_0.6.2 viridisLite_0.4.0

loaded via a namespace (and not attached):
[1] Rcpp_1.0.8 pillar_1.7.0 compiler_3.6.3 bslib_0.3.1 later_1.3.0 jquerylib_0.1.4 tools_3.6.3 dotCall64_1.0-1 digest_0.6.29 lattice_0.20-40
[11] jsonlite_1.8.0 lifecycle_1.0.1 tibble_3.1.8 gtable_0.3.0 pkgconfig_2.0.3 rlang_1.0.4 cli_3.1.1 fastmap_1.1.0 terra_1.5-21 gridExtra_2.3
[21] maps_3.4.0 vctrs_0.3.8 sass_0.4.1 grid_3.6.3 glue_1.6.2 R6_2.5.1 fansi_1.0.2 ggplot2_3.3.6 codetools_0.2-16 scales_1.2.0
[31] promises_1.2.0.1 ellipsis_0.3.2 htmltools_0.5.2 mime_0.12 colorspace_2.0-3 xtable_1.8-4 httpuv_1.6.5 utf8_1.2.2 munsell_0.5.0 crayon_1.5.0

Thank you very much for your help!

[ismirsehregal]

Are you using file.choose to open the shp files?

If this is the case it will only work on the PC hosting the R session.

Consider using fileInput to allow users to upload files.

However, regarding this please keep in mind:

By default, the user can only upload files up to 5 MB. You can increase this limit by setting the shiny.maxRequestSize option prior to starting Shiny. For example, to allow up to 10 MB run options(shiny.maxRequestSize = 10 * 1024^2).

source:

Chapter 9 Uploads and downloads | Mastering Shiny

[Lorena_Ferreira]

Thank you for the answer ismirsehregal!

No no, I am using readOGR from rgdal package. I am using selectInput for the options of the shp files, I leave the user to decide but only with a limit of possibilities. Could it be readOGR the problem?

I know Mastering Shiny book, it is a very wonderful book. Thanks!

[ismirsehregal]

That sounds like a reasonable approach. I don't think readOGR causes a problem if it works when accessed from another client PC.

Are there any messages in the browser's console?

[Lorena_Ferreira]

No, the message I get is this one:

Loading required package: shiny
Loading required package: viridisLite

Attaching package: ‘shinydashboard’

The following object is masked from ‘package:graphics’:

box

Loading required package: sp
Please note that rgdal will be retired by the end of 2023,
plan transition to sf/stars/terra functions using GDAL and PROJ
at your earliest convenience.

rgdal: version: 1.5-32, (SVN revision 1176)
Geospatial Data Abstraction Library extensions to R successfully loaded
Loaded GDAL runtime: GDAL 3.0.4, released 2020/01/28
Path to GDAL shared files: /usr/share/gdal
GDAL binary built with GEOS: TRUE
Loaded PROJ runtime: Rel. 6.3.1, February 10th, 2020, [PJ_VERSION: 631]
Path to PROJ shared files: /usr/share/proj
Linking to sp version:1.5-0
To mute warnings of possible GDAL/OSR exportToProj4() degradation,
use options("rgdal_show_exportToProj4_warnings"="none") before loading sp or rgdal.
Loading required package: spam
Spam version 2.8-0 (2022-01-05) is loaded.
Type 'help( Spam)' or 'demo( spam)' for a short introduction
and overview of this package.
Help for individual functions is also obtained by adding the
suffix '.spam' to the function name, e.g. 'help( chol.spam)'.

Attaching package: ‘spam’

The following objects are masked from ‘package:base’:

backsolve, forwardsolve

Try help(fields) to get started.
The name provided ('refresh') is deprecated in Font Awesome 5:

• please consider using 'sync' or 'fas fa-sync' instead
• use the verify_fa = FALSE to deactivate these messages

Listening on http://127.0.0.1:5381

And then, it should appear the messages of readOGR but I don't get them. Could be a problem of firewall or something like that?

[ismirsehregal]

That's the output of your R console. How about the output of your browser's console when trying to access the shiny app? In e.g. chrome use ctrl+shift+i to access the console.

[Lorena_Ferreira]

Ah ok yes, sorry. No, I don't get messages. Nothing at all. You only get the UI visualization.

[Lorena_Ferreira]

Hello again to everyone,

Does anyone know what it could be the problem?

Thank you!