How can I save a networkD3::sankeyNetwork() into a static image automatically via rmarkdown?

Question

When I write a report in rmarkdown, all my figures as save automatically under the folder graphs. However, as a Sankey diagram is different, it does not save as a picture (.png, etc...) automatically. Is there a workaround for this? (without manually saving each diagram via RStudio Plots panel?)

I saw this question before. But the option from rbokeh produces a low quality graphic. I tried to use the second option, but it seems that there is an error in the code, because the function throws object 'vl' not found.

As that question is from three years ago, I think that there may be a better solution so far.

Example graphic that I want to save:

---
title: "Untitled"
author: "Guilherme"
date: "12/5/2020"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE,
                      fig.path = "graph/")
```

```{r}
library(networkD3)
URL <- paste0('https://cdn.rawgit.com/christophergandrud/networkD3/',
              'master/JSONdata/energy.json')
energy <- jsonlite::fromJSON(URL)

# Plot
sankeyNetwork(Links = energy$links, Nodes = energy$nodes, Source = 'source',
             Target = 'target', Value = 'value', NodeID = 'name',
             units = 'TWh', fontSize = 12, nodeWidth = 30)
```

Malarkey

is there a way to save as PDF rather than a PNG? – Pointed

Answer 1

What about something like this:

--
title: "sankey as image"
author: "..."
date: "12/5/2020"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE,
                      fig.path = "graph/")
```

```{r, fig.align='center'}
library(networkD3)
URL <- paste0('https://cdn.rawgit.com/christophergandrud/networkD3/',
              'master/JSONdata/energy.json')
energy <- jsonlite::fromJSON(URL)

# Plot
sn <- sankeyNetwork(Links = energy$links, Nodes = energy$nodes, Source = 'source',
             Target = 'target', Value = 'value', NodeID = 'name',
             units = 'TWh', fontSize = 12, nodeWidth = 30)

# you save it as an html
saveNetwork(sn, "sn.html")

library(webshot)
# you convert it as png
webshot("sn.html","sn.png", vwidth = 1000, vheight = 900)
```

Lovieloving

I was messing with webshot, but couldn't figure it out. I didn't know about the saveNetwork() function, so that was good to learn. – Marielamariele

It returns the following error to me: TypeError: Attempting to change the setter of an unconfigurable property. TypeError: Attempting to change the setter of an unconfigurable property. And the screenshot is not taken – Malarkey

I reinstall the phantomjs package and it works right now – Malarkey

Same error, and after installing phantomjs. – Northerly