Feature Request: Remove traces by name using plotlyProxy()

I originally posted this as a long shot stack overflow question, but I'm suspecting the functionality I'm looking for might require some new code.

When using plotlyProxy(), adding new traces with a name attribute is very straightforward. However, removing a trace by name does not appear to be possible. Reviewing the plotly.Js function reference, it appears that the JavaScript methods exclusively use indices, so this might require an additional javascript method to match names to trace numbers.

The example shiny app below illustrates the functionality I'm looking for. In the screenshot, when the user clicked the "Remove Trace" button, trace xxx would be removed.

library(shiny)
library(plotly)

ui <- fluidPage(
  textInput("TraceName", "Trace Name"),
  actionButton("Add","Add Trace"),
  actionButton("Remove","Remove Trace"),
  plotlyOutput("MyPlot")
)

server <- function(input,output,session) {

  ## Creating the plot
  output$MyPlot <- renderPlotly({
    plot_ly() %>%
      layout(showlegend  = TRUE)
  })

  ## Adding traces is smooth sailing
  observeEvent(input$Add,{
    plotlyProxy("MyPlot", session) %>%
      plotlyProxyInvoke("addTraces", list(x = rnorm(10),y = rnorm(10),
                                          type = "scatter",mode = "markers",
                                          name = input$TraceName))
  })

  ## Ideal Solution (that does not work)
  observeEvent(input$Remove,{
    plotlyProxy("MyPlot", session) %>%
      plotlyProxyInvoke("deleteTraces", input$TraceName)
  })

}

JavaScript is not my strong suit, but it seems like one way to support this would be to add a new method in htmlwidgets/plotly.js, perhaps called traceNamesToIDs. Then, the steps might look something like the following.

DeleteTraceNames <- c("xxx")
MyPlotProxy <- plotlyProxy("MyPlot", session)
TraceNumberList <- plotlyProxyInvoke(MyPlotProxy, "traceNamesToIds", )) ## Returns c(0)
plotlyProxyInvoke(MyPlotProxy ,"deleteTraces", TraceNumberList )

I'm not quite sure, but as I read through htmlwidgets/plotly.js, it seems like there is already some very similar functionality in the codebase to support Cross Talk integration.

Alternatively, if the deleteTraces method could be modified to directly accept names as a character input, that seems like the most intuitive usage from a user standpoint. However, this might result in breaking changes for users who wrote code based on trace numbers depending on the details of implementation.

plotlyProxy("MyPlot", session) %>%
    plotlyProxyInvoke("deleteTraces", c("xxx"))

If some implementation of this functionality could be added in future versions, I think it could make a substantial difference in the ease of use!

Bắt đầu bằng cách đọc inst/htmlwidgets/plotly.js, đặc biệt là phần xử lý plotlyProxyInvoke và chức năng hiện có liên quan đến Cross Talk được đề cập trong issue. Sau đó, tái hiện ứng dụng Shiny được cung cấp và so sánh hành vi của deleteTraces khi dùng tên trace với khi dùng chỉ mục trace. Công việc được hoàn tất khi ví dụ có thể xóa trace được chọn theo tên mà không làm hỏng cách sử dụng hiện có dựa trên chỉ mục.