Be lenient about Connection header contents when Upgrade header is present

[jcheng5]

This is a workaround for rstudio/rstudio#2940. It
stops an erroneously sent "Connection: close" header from breaking an
otherwise legit websocket request.

Testing notes

Log into an RStudio Server (rstudio.cloud doesn't count, maybe because they run through a proxy) using Firefox. Do shiny::runExample("01_hello"). If httpuv is 1.4.x, the app will launch but immediately disconnect without rendering output. (Older versions of httpuv don't have the problem.)

[jspiewak]

@jcheng5 yes, rstudio.cloud has a proxy, but this still needs to work on rstudio.cloud and remains broken with httpuv 1.4.4.2

[jcheng5]

@jspiewak Oh, I wasn't able to repro the problem on rstudio.cloud, that's why I said that. You're seeing the grey-out with these exact repro steps?

[jspiewak]

@jcheng5 https://community.rstudio.com/t/shiny-app-greys-out-in-rstudio-cloud-error-during-websocket-handshake/10422 plus another that was reported directly to Robby.

[wch]

@jcheng5 I've been able to reproduce it and am investigating now. It doesn't happen with all apps.

[wch]

I dug around in the code a little bit and found a smaller example that crashes about 50% of the time on rstudio.cloud.

# devtools::install_github("skranz/restorepoint")
# devtools::install_github("skranz/shinyEvents")

library(shinyEvents)

# Create a new eventsApp
app = eventsApp()

app$ui = fluidPage(
  textInput("input_name","Your Name")
)

viewApp(app)

[wch]

Hm, even runExample('01_hello') seems to crash most of the time for me.

> sessioninfo::session_info()
Failed to create bus connection: No such file or directory
─ Session info ────────────────────────────────────────────────────────────────────────────────
 setting  value                       
 version  R version 3.5.0 (2018-04-23)
 os       Ubuntu 16.04.4 LTS          
 system   x86_64, linux-gnu           
 ui       RStudio                     
 language (EN)                        
 collate  C.UTF-8                     
 tz       Etc/UTC                     
 date     2018-07-03                  

─ Packages ────────────────────────────────────────────────────────────────────────────────────
 package      * version date       source        
 clisymbols     1.2.0   2017-05-21 RSPM (R 3.5.0)
 digest         0.6.15  2018-01-28 RSPM (R 3.5.0)
 htmltools      0.3.6   2017-04-28 RSPM (R 3.5.0)
 httpuv         1.4.4.2 2018-07-02 CRAN (R 3.5.0)
 jsonlite       1.5     2017-06-01 RSPM (R 3.5.0)
 later          0.7.3   2018-06-08 RSPM (R 3.5.0)
 magrittr       1.5     2014-11-22 RSPM (R 3.5.0)
 mime           0.5     2016-07-07 RSPM (R 3.5.0)
 promises       1.0.1   2018-04-13 RSPM (R 3.5.0)
 R6             2.2.2   2017-06-17 RSPM (R 3.5.0)
 Rcpp           0.12.17 2018-05-18 RSPM (R 3.5.0)
 restorepoint * 0.1.8   2018-07-03 local         
 rlang          0.2.1   2018-05-30 RSPM (R 3.5.0)
 rstudioapi   * 0.7     2017-09-07 RSPM (R 3.5.0)
 sessioninfo    1.0.0   2017-06-21 RSPM (R 3.5.0)
 shiny        * 1.1.0   2018-05-17 RSPM (R 3.5.0)
 shinyEvents  * 2.3     2018-07-03 local         
 withr          2.1.2   2018-03-15 RSPM (R 3.5.0)
 xtable         1.8-2   2016-02-05 RSPM (R 3.5.0)

[dernapo]

I have the same issue, when I run shiny::runExample('01_hello', display.mode="normal") I get a gray screen. Is there any work around? Thanks!

> sessionInfo()
R version 3.6.0 (2019-04-26)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 18.04.2 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.7.1
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.7.1

Random number generation:
 RNG:     Mersenne-Twister 
 Normal:  Inversion 
 Sample:  Rounding 
 
locale:
 [1] LC_CTYPE=de_DE.UTF-8       LC_NUMERIC=C               LC_TIME=de_DE.UTF-8        LC_COLLATE=de_DE.UTF-8    
 [5] LC_MONETARY=de_DE.UTF-8    LC_MESSAGES=de_DE.UTF-8    LC_PAPER=de_DE.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C             LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=C       

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

other attached packages:
[1] ggplot2_3.2.0 **shiny_1.3.2**  

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.1        rstudioapi_0.10   magrittr_1.5      tidyselect_0.2.5  munsell_0.5.0     colorspace_1.4-1 
 [7] xtable_1.8-4      R6_2.4.0          rlang_0.3.4       dplyr_0.8.1       tools_3.6.0       grid_3.6.0       
[13] packrat_0.5.0     gtable_0.3.0      sessioninfo_1.1.1 cli_1.1.0         withr_2.1.2       htmltools_0.3.6  
[19] assertthat_0.2.1  lazyeval_0.2.2    digest_0.6.19     tibble_2.1.2      crayon_1.3.4      purrr_0.3.2      
[25] later_0.8.0       promises_1.0.1    rsconnect_0.8.13  glue_1.3.1        mime_0.7          compiler_3.6.0   
[31] pillar_1.4.1      scales_1.0.0      **httpuv_1.5.1**      pkgconfig_2.0.2  

[jcheng5]

@dernapo Are you on rstudio.cloud, RStudio Server (Pro), or RStudio desktop? And if one of the latter two, what version?

If not desktop then installing httpuv from GitHub master may help--if that works then you likely have a misconfigured nginx proxy between you and RStudio. See https://community.rstudio.com/t/shiny-v1-3-known-regressions-and-serious-issues/28180/4

[dernapo]

Hi @jcheng5 I am using RStudio Server Version 1.2.1335, no NGINX but Apache 2.4.
Tried with installing httpuv from GitHub but still not working :(