Improve animint2pages by automatically taking screenshot of the animint

[siddhesh195]

This pull request is a part of GSoC 2024 task of adding the feature of automatic screenshot in animint2pages function.

[tdhock]

great thanks for sharing. can yoiu please convert the PR to draft until it is ready for review?

[tdhock]

I manually tested the functionality by running the code below,

library(animint2)
mtcars$Cyl <- factor(mtcars$cyl)
viz <- animint(
  ggplot(mtcars, aes(x = mpg, y = disp, color=Cyl)) +
    geom_point(),
  ggplot(mtcars, aes(x = hp, y = wt, color=Cyl)) +
    geom_point(),
  title="Motor Trend Cars data viz",
  source="https://github.com/animint/animint2/blob/master/R/z_pages.R"
)
animint2pages(viz, "2024-08-29-screenshot-test")

which gave me this viz https://tdhock.github.io/2024-08-29-screenshot-test/ and the screenshot below,

overall the functionality looks great, but the widgets at the bottom are undesirable.
So I just pushed a commit which re-arranges the plots and widgets into a table, with a new <td class="plot_content"> so we can use screenshot(selector=".plot_content") to screenshot only the plots (not the widgets).
https://rstudio.github.io/chromote/reference/ChromoteSession.html#method-screenshot-

That results in the image below,

(without widgets at the bottom)

[siddhesh195]

I manually tested the functionality by running the code below,

library(animint2)
mtcars$Cyl <- factor(mtcars$cyl)
viz <- animint(
  ggplot(mtcars, aes(x = mpg, y = disp, color=Cyl)) +
    geom_point(),
  ggplot(mtcars, aes(x = hp, y = wt, color=Cyl)) +
    geom_point(),
  title="Motor Trend Cars data viz",
  source="https://github.com/animint/animint2/blob/master/R/z_pages.R"
)
animint2pages(viz, "2024-08-29-screenshot-test")

which gave me this viz https://tdhock.github.io/2024-08-29-screenshot-test/ and the screenshot below, overall the functionality looks great, but the widgets at the bottom are undesirable. So I just pushed a commit which re-arranges the plots and widgets into a table, with a new <td class="plot_content"> so we can use screenshot(selector=".plot_content") to screenshot only the plots (not the widgets). https://rstudio.github.io/chromote/reference/ChromoteSession.html#method-screenshot-

That results in the image below, (without widgets at the bottom)

yes. now the screenshots are better. widgets are not necessary in the screenshot. thank you for pointing that out and making a commit. I will look into it to understand the changes you made

[tdhock]

this functionality (starting a server using servr::httd) seems duplicated here, and when printing animint, and in tests_init. is there some way to combine the repeated logic into a helper function?

[siddhesh195]

@tdhock, I resolved all the comments. Can you please have another look to see if the PR is now ready to be merged ?

[siddhesh195]

hello @tdhock , is there anything more that needs to refactored before merging this PR ?

[tdhock]

two different spellings of server, in start_servr and stop_server, is potentially confusing. please change to stop_servr for consistency.

[tdhock]

great, thanks for your patience! this is a really useful contribution.