cranlogs-alt-solution

cranlogs-alt-solution

# Could this be an alternative solution for the following?
# https://github.com/jcheng5/rstudio2017-shiny-workshop/blob/master/apps/reactivity/cranlogs.solution.R

library(cranlogs)
library(dplyr)
library(lubridate)
library(ggplot2)
library(shiny)

# Define UI for specifying package and plotting cranlogs ------------
ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      textInput("packages", "Package names (comma separated)"),
      actionButton("update", "Update")
    ),
    mainPanel(
      plotOutput("plot")
    )
  )
)

# Define server logic for downloading and parsing cranlogs ----------
server <- function(input, output, session) {
  
  # Parses comma-separated string into a proper vector
  packages <- reactive(strsplit(input$packages, " *, *")[[1]])
  
  # Daily downloads
  daily_downloads <- reactive({
    cranlogs::cran_downloads(
      packages = packages(),
      from = "2016-01-01", to = "2016-12-31"
    )
  })
  
  # Weekly downloads
  weekly_downloads <- reactive({
    daily_downloads() %>% mutate(date = ceiling_date(date, "week")) %>%
      group_by(date, package) %>%
      summarise(count = sum(count))
  })
  
  observeEvent(input$update,{
    # Plot weekly downloads, plus trendline
    output$plot <- renderPlot({
      ggplot(weekly_downloads(), aes(date, count, color = package)) +
        geom_line() +
        geom_smooth()
    })
    }
    )

}

# Run the app -------------------------------------------------------
shinyApp(ui, server)