Add WW_HISTFILE to control shell history location during wwctl image shell

Co-authored-by: Christian Goll <cgoll@suse.com>

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

CHANGELOG.md

@@ -14,6 +14,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Added `UniqueField` template function. #829
 - Added `wwctl image build --syncuser`. #1321
 - Added support for a DNSSEARCH netdev tag in network configuration overlays. #1256
+- Added `WW_HISTFILE` to control shell history location during `wwctl image shell`. #1732
 
 ### Changed
 

internal/app/wwctl/image/exec/child/main.go

@@ -170,6 +170,8 @@ func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 		return fmt.Errorf("failed to mount /run: %w", err)
 	}
 
+	os.Setenv("PATH", "/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin")
+
 	var ps1Base string
 	if v, ok := os.LookupEnv("WW_PS1"); ok {
 		ps1Base = v
@@ -177,10 +179,16 @@ func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 		ps1Base = `\w\$ `
 		os.Setenv("WW_PS1", ps1Base)
 	}
-
 	os.Setenv("PS1", fmt.Sprintf("%s %s", ps1Prefix, ps1Base))
-	os.Setenv("PATH", "/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin")
-	os.Setenv("HISTFILE", "/dev/null")
+
+	var histfile string
+	if v, ok := os.LookupEnv("WW_HISTFILE"); ok {
+		histfile = v
+	} else {
+		histfile = "/dev/null"
+		os.Setenv("WW_HISTFILE", histfile)
+	}
+	os.Setenv("HISTFILE", histfile)
 
 	wwlog.Debug("Exec: %s %s", args[1], args[1:])
 	return syscall.Exec(args[1], args[1:], os.Environ())

userdocs/contents/images.rst

@@ -306,6 +306,16 @@ construct the final ``PS1`` variable for the shell.
    # env WW_PS1="\u@\h:\w\$ " wwctl image shell rockylinux-9
    [warewulf:rockylinux-9] root@rocky:/$
 
+Shell history
+-------------
+
+By default, Warewulf image shell sessions don't retain history; but you can
+specify a history file by specifing ``WW_HISTFILE``. Note that this file is
+stored within the image; you may want to exclude it when the image is built.
+(See :ref:`exclude`.)
+
+.. _exclude:
+
 Excluding Files from an Image
 -----------------------------