Value Metrics Module

Access Instructions

The project used for this particular exercise is hosted on Posit Cloud in this space. The project for this exercise is called modules-exercise1.

Exercise Instructions

Your task is to create a new Shiny module that displays three important metrics to the user:

• Total number of sets
• Total number of parts among the sets
• Total number of mini-figures

Note that these quantities are dependent on the user selections from the inputs contained in the left sidebar (theme, year, and parts range).

Keeping with the overall user interface style, you are recommended to use the value_box function from the {bslib} package. The metrics can be derived using the function below. In the application code, you will find reactive data frames called sets_rv and part_meta_rv which can be used in the parameters of the function below.

#' Derive key LEGO data set metrics
#' 
#' @param sets_rv data frame containing sets information
#' @param part_meta_rv data frame containing parts metadata information
#' 
#' @import dplyr
derive_widget_metrics <- function(sets_rv, part_meta_rv) {
  # number of sets
  n_sets <- length(unique(sets_rv$set_num))

  # number of parts
  n_parts <- sum(sets_rv$num_parts, na.rm = TRUE)

  # number of minifigs
  n_minifigs <- part_meta_rv |>
    summarize(total_minifigs = sum(minifig_ind)) |>
    collect() |>
    pull(total_minifigs)

  return(
    list(
      n_sets = n_sets,
      n_parts = n_parts,
      n_minifigs = n_minifigs
    )
  )
}