make 'create_tree' function faster

[eblondel]

Hi @pvictor, here's some PR that intends to make create_tree faster.

WIth this PR, I led to decrease significantly the time required to build a tree for a large list of levels.

The context on which i'm working and that led to this PR is a R shiny app r-geoflow/geoflow-shiny as UI for for the R package r-geoflow/geoflow, in which i'm building a metadata editor that connects to vocabulary servers (powered by RDF/SKOS vocabularies). Some of these vocabularies can be very large, handling many collections of concepts.

See below a script that summaries the benchmarking I did on some large vocabulary (with 131,689 records). I attach the vocabular mentioned in this script as CSV, in case you want to reproduce. The code runs 25x faster with this PR.

#create_tree benchmarking

require(shinyWidgets)
require(readr)
require(waldo)

# Data queried through geoflow package
# provided as CSV for convenience

# if(!require(geoflow)){
#   remotes::install_github("r-geoflow/geoflow")
#   require(geoflow)
# }
# vocab = geoflow::list_vocabularies(raw = T)[[3]]
# concepts = vocab$list_concepts()
concepts <- readr::read_csv("concepts.csv")

#build tree from above concepts
system.time(
  tree1 <- shinyWidgets::create_tree(
    concepts,
    levels = c("collectionLabel", "prefLabel"), 
    levels_id = c("collection", "concept")
  )
)
#-------------------------------------------
## => master
## user    system  ellapsed 
## 35.79   0.58    41.10
#-------------------------------------------

#run after PR shinyWidgets install
system.time(
  tree2 <- shinyWidgets::create_tree(
    concepts,
    levels = c("collectionLabel", "prefLabel"), 
    levels_id = c("collection", "concept")
  )
)
#-------------------------------------------
## => PR
## user    system  ellapsed
## 1.46    0.12    1.65
#-------------------------------------------

#qa with waldo
waldo::compare(tree1, tree2)
#-------------------------------------------
## ✔ No differences
#-------------------------------------------

[pvictor]

Hello,
Thank you for this. I tried it quickly and didn't see the same performance gain, I'll find some time to look into it further.

[eblondel]

concepts.zip
Here's the file I used in the above test. I though it was attached, but the size was too high apparently.