Rebuild overlays for discovered nodes

- Fixes: #1468

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

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## Unreleased
+
+### Changed
+
+- `warewulfd` overlay autobuild rebuilds overlays after node discovery. #1468
+
 ## v4.6.2, 2025-07-09
 
 ### Added

internal/pkg/overlay/config.go

@@ -105,3 +105,19 @@ func OverlayImage(nodeName string, context string, overlayNames []string) string
 
 	return path.Join(config.Get().Paths.OverlayProvisiondir(), nodeName, name)
 }
+
+func ClearOverlayImage(nodeName string, context string, overlayNames []string) error {
+	imagePath := OverlayImage(nodeName, context, overlayNames)
+	if util.IsFile(imagePath) {
+		if err := os.Remove(imagePath); err != nil {
+			return fmt.Errorf("failed to remove overlay image: %w", err)
+		}
+	}
+	compressedImagePath := imagePath + ".gz"
+	if util.IsFile(compressedImagePath) {
+		if err := os.Remove(compressedImagePath); err != nil {
+			return fmt.Errorf("failed to remove compressed overlay image: %w", err)
+		}
+	}
+	return nil
+}

internal/pkg/warewulfd/nodedb.go

@@ -6,6 +6,7 @@ import (
 	"sync"
 
 	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/pkg/overlay"
 	"github.com/warewulf/warewulf/internal/pkg/wwlog"
 )
 
@@ -53,7 +54,7 @@ func loadNodeDB() (err error) {
 	return nil
 }
 
-func GetNodeOrSetDiscoverable(hwaddr string) (node.Node, error) {
+func GetNodeOrSetDiscoverable(hwaddr string, autobuildOverlays bool) (node.Node, error) {
 	db.lock.RLock()
 	defer db.lock.RUnlock()
 	// NOTE: since discoverable nodes will write an updated DB to file and then
@@ -97,9 +98,14 @@ func GetNodeOrSetDiscoverable(hwaddr string) (node.Node, error) {
 	if err != nil {
 		return nodeFound, fmt.Errorf("%s (failed to reload configuration) %w", hwaddr, err)
 	}
-	// NOTE: previously all overlays were built here, but that will also
+	if autobuildOverlays {
-	// be done automatically when attempting to serve an overlay that
+		if err := overlay.ClearOverlayImage(nodeFound.Id(), "system", []string{}); err != nil {
-	// hasn't been built (without blocking the database).
+			wwlog.Warn("Failed to clear system overlay image: %s: %s", nodeFound.Id(), err)
+		}
+		if err := overlay.ClearOverlayImage(nodeFound.Id(), "runtime", []string{}); err != nil {
+			wwlog.Warn("Failed to clear runtime overlay image: %s: %s", nodeFound.Id(), err)
+		}
+	}
 
 	wwlog.Serv("%s (node %s automatically configured)", hwaddr, nodeFound.Id())
 

internal/pkg/warewulfd/nodedb_test.go

@@ -10,10 +10,12 @@ import (
 
 func Test_GetNodeOrSetDiscoverable(t *testing.T) {
 	var tests = map[string]struct {
-		nodesConf string
+		nodesConf    string
-		hwaddr    string
+		hwaddr       string
-		node      string
+		node         string
-		err       bool
+		err          bool
+		initFiles    []string
+		removedFiles []string
 	}{
 		"empty": {
 			nodesConf: `
@@ -40,6 +42,29 @@ nodes:
     discoverable: true
     network devices:
       default: {}
+`,
+			hwaddr: "00:00:00:00:00:01",
+			node:   "n1",
+		},
+		"discoverable autobuild": {
+			initFiles: []string{
+				"/srv/warewulf/overlays/n1/__SYSTEM__.img",
+				"/srv/warewulf/overlays/n1/__SYSTEM__.img.gz",
+				"/srv/warewulf/overlays/n1/__RUNTIME__.img",
+				"/srv/warewulf/overlays/n1/__RUNTIME__.img.gz",
+			},
+			removedFiles: []string{
+				"/srv/warewulf/overlays/n1/__SYSTEM__.img",
+				"/srv/warewulf/overlays/n1/__SYSTEM__.img.gz",
+				"/srv/warewulf/overlays/n1/__RUNTIME__.img",
+				"/srv/warewulf/overlays/n1/__RUNTIME__.img.gz",
+			},
+			nodesConf: `
+nodes:
+  n1:
+    discoverable: true
+    network devices:
+      default: {}
 `,
 			hwaddr: "00:00:00:00:00:01",
 			node:   "n1",
@@ -77,20 +102,25 @@ nodes:
 	for name, tt := range tests {
 		t.Run(name, func(t *testing.T) {
 			env := testenv.New(t)
+			for _, file := range tt.initFiles {
+				env.CreateFile(file)
+			}
 			defer env.RemoveAll()
 			env.WriteFile("/etc/warewulf/nodes.conf", tt.nodesConf)
 
 			err := LoadNodeDB()
 			assert.NoError(t, err)
 
-			node, err := GetNodeOrSetDiscoverable(tt.hwaddr)
+			node, err := GetNodeOrSetDiscoverable(tt.hwaddr, true)
 			if tt.err {
 				assert.Error(t, err)
 			} else {
 				assert.NoError(t, err)
 				assert.Equal(t, tt.node, node.Id())
 			}
+			for _, file := range tt.removedFiles {
+				assert.NoFileExists(t, env.GetPath(file), "File should not exist: %s", file)
+			}
 		})
 	}
-
 }

internal/pkg/warewulfd/provision.go

@@ -76,7 +76,7 @@ func ProvisionSend(w http.ResponseWriter, req *http.Request) {
 	// TODO: when module version is upgraded to go1.18, should be 'any' type
 	var tmpl_data *templateVars
 
-	remoteNode, err := GetNodeOrSetDiscoverable(rinfo.hwaddr)
+	remoteNode, err := GetNodeOrSetDiscoverable(rinfo.hwaddr, conf.Warewulf.AutobuildOverlays())
 	if err != nil && err != node.ErrNoUnconfigured {
 		wwlog.ErrorExc(err, "")
 		w.WriteHeader(http.StatusServiceUnavailable)