docklet_create() returns "Error: You specified an invalid image for Droplet creation."

I'm trying to create a docklet to run RStudio Server. It looks like the default image name for that is "docker" from the documentation of docklet_create. But d <- docklet_create() returns an error:

> d <- docklet_create()
Using default ssh keys: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Error: You specified an invalid image for Droplet creation.
>

Indeed, images() returns 25 image names, none of which is "docker":

> image_list <- images()
> names(image_list)
 [1] "2051.2.0 (beta)"                           
 [2] "Cassandra on 14.04"                        
 [3] "10.3 x64 zfs"                              
 [4] "10.3 x64"                                  
 [5] "14.04.5 x32"                               
 [6] "11.1 x64"                                  
 [7] "11.1 x64 ZFS"                              
 [8] "10.4 x64 ZFS"                              
 [9] "10.4 x64"                                  
[10] "MachineLearning on 16.04-20171020"         
[11] "27 x64"                                    
[12] "27 x64 Atomic"                             
[13] "6.9 x32"                                   
[14] "14.04.5 LTS x64 HWE"                       
[15] "8.10 x64"                                  
[16] "8.10 x32"                                  
[17] "28 x64"                                    
[18] "28 x64 Atomic"                             
[19] "cloudbench-nullworkload-on-1604.051818-1"  
[20] "cloudbench-ycsb-cassandra-on-1604.051818-1"
[21] "cloudbench-hibench-hadoop-on-1604.061818-1"
[22] "7.5 x64"                                   
[23] "6.9 x64"                                   
[24] "MachineLearning on 16.04-20180612"         
[25] "- DigitalOcean Recovery 18.04.20180614"    
>

What image name should I use?

Session Info

```r > devtools::session_info() ─ Session info ─────────────────────────────────────────────────────────────────── setting value version R version 3.5.3 (2019-03-11) os ArcoLinuxD system x86_64, linux-gnu ui RStudio language (EN) collate en_US.UTF-8 ctype en_US.UTF-8 tz America/Los_Angeles date 2019-03-18 ─ Packages ─────────────────────────────────────────────────────────────────────── package * version date lib source analogsea * 0.6.6.9110 2019-03-19 [1] Github (sckott/analogsea@26f3574) askpass 1.1 2019-01-13 [1] CRAN (R 3.5.3) assertthat 0.2.0 2017-04-11 [1] CRAN (R 3.5.3) aws.s3 0.3.12 2018-05-25 [1] CRAN (R 3.5.3) aws.signature 0.4.4 2018-07-27 [1] CRAN (R 3.5.3) backports 1.1.3 2018-12-14 [1] CRAN (R 3.5.3) base64enc 0.1-3 2015-07-28 [1] CRAN (R 3.5.3) callr 3.2.0 2019-03-15 [1] CRAN (R 3.5.3) cli 1.0.1 2018-09-25 [1] CRAN (R 3.5.3) crayon 1.3.4 2017-09-16 [1] CRAN (R 3.5.3) curl 3.3 2019-01-10 [1] CRAN (R 3.5.3) desc 1.2.0 2018-05-01 [1] CRAN (R 3.5.3) devtools 2.0.1 2018-10-26 [1] CRAN (R 3.5.3) digest 0.6.18 2018-10-10 [1] CRAN (R 3.5.3) fs 1.2.6 2018-08-23 [1] CRAN (R 3.5.3) glue 1.3.1 2019-03-12 [1] CRAN (R 3.5.3) httr 1.4.0 2018-12-11 [1] CRAN (R 3.5.3) jsonlite 1.6 2018-12-07 [1] CRAN (R 3.5.3) magrittr 1.5 2014-11-22 [1] CRAN (R 3.5.3) memoise 1.1.0 2017-04-21 [1] CRAN (R 3.5.3) openssl 1.2.2 2019-03-01 [1] CRAN (R 3.5.3) packrat 0.5.0 2018-11-14 [1] CRAN (R 3.5.3) pkgbuild 1.0.2 2018-10-16 [1] CRAN (R 3.5.3) pkgload 1.0.2 2018-10-29 [1] CRAN (R 3.5.3) prettyunits 1.0.2 2015-07-13 [1] CRAN (R 3.5.3) processx 3.3.0 2019-03-10 [1] CRAN (R 3.5.3) ps 1.3.0 2018-12-21 [1] CRAN (R 3.5.3) R6 2.4.0 2019-02-14 [1] CRAN (R 3.5.3) Rcpp 1.0.1 2019-03-17 [1] CRAN (R 3.5.3) remotes 2.0.2 2018-10-30 [1] CRAN (R 3.5.3) rlang 0.3.1 2019-01-08 [1] CRAN (R 3.5.3) rprojroot 1.3-2 2018-01-03 [1] CRAN (R 3.5.3) rstudioapi 0.9.0 2019-01-09 [1] CRAN (R 3.5.3) sessioninfo 1.1.1 2018-11-05 [1] CRAN (R 3.5.3) testthat 2.0.1 2018-10-13 [1] CRAN (R 3.5.3) usethis 1.4.0 2018-08-14 [1] CRAN (R 3.5.3) withr 2.1.2 2018-03-15 [1] CRAN (R 3.5.3) xml2 1.2.0 2018-01-24 [1] CRAN (R 3.5.3) yaml 2.2.0 2018-07-25 [1] CRAN (R 3.5.3) [1] /home/znmeb/R/x86_64-pc-linux-gnu-library/3.5 [2] /usr/lib/R/library ```

pachadotdev / analogsea

docklet_create() returns "Error: You specified an invalid image for Droplet creation." #174