HTML documents including plotly plots are not reproducible

I believe it is known that the value of plotly::plot_ly(x = 1, y = 1)$x$cur_data is hard to reproduce, compare https://github.com/plotly/plotly.R/issues/1048. Some work has been done in #1379 towards use in shinytest at least.

I am also using shinytest, but in my app, users are downloading HTML files with plotly plots generated using rmarkdown::render(). So these files are still non-reproducible because I cannot seem to use renderPlotly() inside rmarkdown::render(). To see the problem:

bug.Rmd:

---
output: html_document
---

```{r}
plotly::plot_ly(x = 1, y = 1)
```

Then run R -q -s -e 'rmarkdown::render("bug.Rmd")' and see the value of cur_data in bug.html change every time you regenerate it.

I see two options:

• I could replicate the logic of
  https://github.com/plotly/plotly.R/blob/bab01af316673e35d8314129178bfb27eed27fe7/R/shiny.R#L46-L53
  inside bug.Rmd, like this:

  p <- plotly::plot_ly(x = 1, y = 1)
  p$x$attrs <- NULL # and a few more
  p
  

  However, this breaks the plot. Any way I can make this work?
• I have also tried putting this inside bug.Rmd:

  shiny::snapshotPreprocessOutput(
    plotly::plot_ly(x = 1, y = 1),
    function(value) {
      # https://github.com/plotly/plotly.R/blob/3d49fbc5897703d58b/R/shiny.R#L68
      json <- jsonlite::from_JSON(value)
      json$x <- json$x[setdiff(names(json$x), c("visdat", "cur_data", "attrs"))]
      # https://github.com/plotly/plotly.R/blob/3d49fbc589/R/utils.R#L1020-L1025
      jsonlite::toJSON(json,
        digits = 50, auto_unbox = TRUE, force = TRUE,
        null = "null", na = "null", time_format = "%Y-%m-%d %H:%M:%OS6"
      )
    }
  )
  

  but rmarkdown::render() seemed to ignore it, even inside shinytest (or did I do anything wrong there)?
• One could amend #1365 to take into account a hash of the current plot serialization to avoid generating identical IDs even if the external seed is reset to the same values externally. This would avoid the need for tempfile().

Riproduci il problema con bug.Rmd e R -q -s -e 'rmarkdown::render("bug.Rmd")', quindi confronta il valore di cur_data in bug.html tra più rendering. Leggi la logica indicata in R/shiny.R e R/utils.R, insieme alle issue correlate #1048, #1379 e #1365. Il lavoro è completato quando i documenti HTML renderizzati con rmarkdown::render() producono dati del grafico riproducibili senza compromettere il grafico.