Make Shiny Autoreload Work

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: rhino
 Title: A Framework for Enterprise Shiny Applications
-Version: 1.5.0.9003
+Version: 1.5.0.9004
 Authors@R:
   c(
     person("Kamil", "Żyła", role = c("aut", "cre"), email = "[email protected]"),

NEWS.md

@@ -10,6 +10,8 @@
     * `lint_sass()` now uses `stylelint` 14.16 (the last major version supporting stylistic rules)
     * Upgrade all remaining Node.js dependencies to latest versions and fix vulnerabilities.
     * The minimum supported Node.js version is now 16.
+4. `shiny.autoreload` now works correctly with `box::use`. Note: this requires
+   `legacy_entrypoint` to be unset.
 
 # [rhino 1.5.0](https://github.com/Appsilon/rhino/releases/tag/v1.5.0)
 

R/app.R

@@ -40,19 +40,25 @@ load_main_module <- function() {
   app <- NULL
   main <- NULL
   box::use(app/main)
-  main
+  main_env <- environment()
+  if (isTRUE(getOption("shiny.autoreload", FALSE))) {
+    shiny:::autoReloadCallbacks$register(function() {
+      evalq(box::reload(main), main_env)
+    })
+  }
+  main_env
 }
 
-as_top_level <- function(shiny_module) {
+as_top_level <- function(shiny_module_env) {
   # Necessary to avoid infinite recursion / bugs due to lazy evaluation:
   # https://adv-r.hadley.nz/function-factories.html?q=force#forcing-evaluation
-  force(shiny_module)
+  force(shiny_module_env)
 
   # The actual function must be sourced with `keep.source = TRUE` for reloading to work:
   # https://github.com/Appsilon/rhino/issues/157
   wrap <- source(fs::path_package("rhino", "as_top_level.R"), keep.source = TRUE)$value
 
-  wrap(shiny_module)
+  wrap(shiny_module_env)
 }
 
 with_head_tags <- function(ui) {
@@ -110,6 +116,8 @@ with_head_tags <- function(ui) {
 #' into a [Shiny module](https://shiny.rstudio.com/articles/modules.html)
 #' (functions taking a single `id` argument).
 #'
+#' Note: `legacy_entrypoint` might not work in conjunction with `shiny.autoreload`.
+#'
 #' @return An object representing the app (can be passed to `shiny::runApp()`).
 #'
 #' @examples
@@ -133,9 +141,11 @@ app <- function() {
     main <- new.env()
     source(fs::path("app", "main.R"), local = main)
   } else {
-    main <- load_main_module()
+    main_env <- load_main_module()
     if (!identical(entrypoint, "box_top_level")) {
-      main <- as_top_level(main)
+      main <- as_top_level(main_env)
+    } else {
+      main <- main_env$main
     }
   }
   shiny::shinyApp(

inst/as_top_level.R

@@ -1,12 +1,12 @@
 # This function is defined in the `inst` directory, as it must be sourced with `keep.source = TRUE`
 # for reloading to work: https://github.com/Appsilon/rhino/issues/157
-function(shiny_module) {
+function(shiny_module_env) {
   list(
     # Wrap the UI in a function to support Shiny bookmarking.
-    ui = function(request) shiny_module$ui("app"),
+    ui = function(request) shiny_module_env$main$ui("app"),
     # The curly braces below are essential: https://github.com/Appsilon/rhino/issues/157
     server = function(input, output) {
-      shiny_module$server("app")
+      shiny_module_env$main$server("app")
     }
   )
 }