gauth shiny example

global.R

library(googleAuthR)
library(shiny)
library(shinyjs)

server.R

function(input,output,session) {
    things <- reactiveValues(user=NULL,auth_message=NULL)

    ## configs    
    local_users <- c("some_person@gmail.com") ## gmail addresses of authorized users

    options(googleAuthR.scopes.selected=c("https://www.googleapis.com/auth/userinfo.email"))
    options("googleAuthR.webapp.client_id"="your_client_id")
    options("googleAuthR.webapp.client_secret"="your_client_secret")
    ## get these values from https://console.developers.google.com/apis/credentials/oauthclient/


    ## handle authentication
    validate_user <- function(user_info,show_modal=TRUE) {
        if (show_modal) {
            showModal(modalDialog("Checking user permissions ...",
                                  title = "Please wait",
                                  fade=FALSE,footer=NULL))
            on.exit(removeModal())
        }
        things$auth_message <- tags$p("Checking user permissions ...")
        ## logged in via google. Are we an authorized user?
        if (user_info$kind=="plus#person") {
            uidx <- any(local_users %in% user_info$emails$value)
            if (any(uidx)) {
                return(local_users[uidx]) ## the matching user email address
            } else {
                ## no
                things$auth_message <- tags$p("You do not have access to this application")
            }
        } else {
            ## not a google-plus object
            things$auth_message <- tags$p("Unexpected login failure")
        }
        NULL
    }
    get_user_info <- function(id="me"){
        url <- sprintf("https://www.googleapis.com/plus/v1/people/%s",id)
        g <- googleAuthR::gar_api_generator(url,"GET")
        req <- g()
        req$content 
    }
    accessToken <- callModule(googleAuth, "gauth_login",
                             logout_text="Logout from Google",
                             login_class="btn btn-primary",
                             logout_class="btn btn-primary")
    observe({
        if (!is.null(accessToken())) {
            removeCssClass("ss-connect-dialog","myhidden")
            showModal(modalDialog("Checking user permissions ...",
                                  title = "Please wait",
                                  fade=FALSE,footer=NULL))
            user_info <- with_shiny(get_user_info,shiny_access_token=accessToken())
            val_user <- validate_user(user_info)
            removeModal()
            if (!is.null(val_user)) {
                things$user <- val_user
            }
        } else {
            ## On firefox, doing the google login shows up the "disconnected from server"
            ## box on shinyapps.io. In lieu of a decent solution, hide this
            addCssClass("ss-connect-dialog","myhidden")
        }
    })

    observe({
        if (!is.null(things$user)) {
            ## Workaround to avoid shinyapps.io URL problems
            shinyjs::onclick("gauth_login-googleAuthUi",
                             shinyjs::runjs("window.location.href='https://yourdomain.shinyapps.io/yourapp';"))
        }
    })
    output$login <- renderUI({
        if (is.null(things$user)) {
            div(style="text-align:right",
                things$auth_message,
                googleAuthUI("gauth_login"))
        } else {
            tags$p(style="text-align:right","User: ",things$user)
        }
    })

    observeEvent(input$show_login,{
        showModal(modalDialog(
            title = "Log in",
            wellPanel(
                googleAuthUI("gauth_login")
            ),
            easyClose=TRUE))
    })

    observeEvent(input$do_login,{
        removeModal()
        if (!is.null(things$user)) {
            things$auth_message <- NULL
        }
    })

    
    output$output1 <- renderUI({
        if (is.null(things$user)) {
            tags$p("Log in for access")
        } else {
            tags$p("Hooray! You have access.")
        }
    })
}

ui.R

fluidPage(useShinyjs(),
          tags$head(
                   tags$style(".myhidden {display:none;}"), ## to hide selected elements
                   tags$title("Shiny Google auth example")
               ),
          uiOutput(style="clear:right;","login"),
          uiOutput("output1")
)