fixed getting loglevel/file from env vars

R/logging.r

@@ -47,13 +47,13 @@ log_msg_stderror <- function(lvl, msg){
 })
 
 log_msg_logfile <- function(lvl, msg) {
-	if (!is.null(getOption('jupyter.logfile'))) {
-		cur_logfile <- getOption('jupyter.logfile')
-		if (.is_changed_logfile(cur_logfile)) {
-			log_msg_stderror('INFO', sprintf('Logging to %s', cur_logfile))
-		}
-		log_con <- file(cur_logfile, open='ab')
-		writeBin(charToRaw(sprintf('%s %s: %s\n', format(Sys.time()), lvl, msg)), log_con, endian = 'little')
-		close(log_con)
-	}
+    cur_logfile <- getOption('jupyter.logfile')
+    if (!is.na(cur_logfile)) {
+        if (.is_changed_logfile(cur_logfile)) {
+            log_msg_stderror('INFO', sprintf('Logging to %s', cur_logfile))
+        }
+        log_con <- file(cur_logfile, open = 'ab')
+        writeBin(charToRaw(sprintf('%s %s: %s\n', format(Sys.time()), lvl, msg)), log_con, endian = 'little')
+        close(log_con)
+    }
 }

R/options.r

@@ -1,8 +1,3 @@
-getenv_default <- function(varname, default) {
-    value <- Sys.getenv(varname)
-    if (identical(value, '')) default else value
-}
-
 #' @usage \code{
 #' options(jupyter.* = ...)
 #' getOption('jupyter.*')
@@ -11,8 +6,8 @@ getenv_default <- function(varname, default) {
 #' @name IRkernel
 #' @export
 jupyter_option_defaults <- list(
-    jupyter.log_level = as.integer(getenv_default('JUPYTER_LOG_LEVEL', 1L)),
-    jupyter.logfile = getenv_default('JUPYTER_LOGFILE', NULL),
+    jupyter.log_level = 1L,
+    jupyter.logfile = NA,
     jupyter.pager_classes = c(
         'help_files_with_topic'),
     jupyter.plot_mimetypes = c(
@@ -21,10 +16,28 @@ jupyter_option_defaults <- list(
         'image/svg+xml'),
     jupyter.in_kernel = FALSE)
 
+from_env <- list(
+    JUPYTER_LOG_LEVEL = as.integer,
+    JUPYTER_LOGFILE = function(f) if (nchar(f) == 0) NA else f)
+
+# converts e.g. jupyter.log_level to JUPYTER_LOG_LEVEL
+opt_to_env <- function(nms) gsub('.', '_', toupper(nms), fixed = TRUE)
+
 .onLoad <- function(libname = NULL, pkgname = NULL) {
     for (opt_name in names(jupyter_option_defaults)) {
+        # skip option if it is set to NULL (unset)
         if (is.null(getOption(opt_name))) {
-            do.call(options, jupyter_option_defaults[opt_name])  # single []: preserve name
+            # prepare `options` call from the default
+            call_arg <- jupyter_option_defaults[opt_name]  # single [] preserve names
+
+            # if an env var is set, get value from it.
+            env_name <- opt_to_env(opt_name)
+            convert <- from_env[[env_name]]
+            env_val <- Sys.getenv(env_name, unset = NA)
+            if (!is.null(convert) && !is.na(env_val))
+                call_arg[[opt_name]] <- convert(env_val)
+
+            do.call(options, call_arg)
         }
     }
 }