Fix newline handling in file, softlink, and ImportLink template functions

Use state-based routing instead of sentinel strings, so whitespace-trimming syntax (e.g. `{{- file "name" -}}`) correctly creates all named files and symlinks. Fixes: #2118 Signed-off-by: Jonathon Anderson <janderson@ciq.com> Co-authored-by: Christian Goll <cgoll@suse.com> Signed-off-by: Jonathon Anderson <janderson@ciq.com>
2026-04-17 15:57:19 -06:00
parent eaac55a97a
commit 2bad789f4f
28 changed files with 767 additions and 256 deletions
--- a/internal/pkg/warewulfd/api/overlay.go
+++ b/internal/pkg/warewulfd/api/overlay.go
@@ -6,6 +6,7 @@ import (
 	"net/url"
 	"os"
 	"path"
+	"strings"
 	"syscall"

 	"github.com/swaggest/usecase"
@@ -148,12 +149,46 @@ func (of *OverlayFile) renderContents(nodeName string) (string, error) {
 	}
 	tstruct.BuildSource = of.Path

-	buffer, _, _, renderErr := overlay.RenderTemplateFile(of.FullPath(), tstruct)
+	rendered, renderErr := overlay.RenderTemplate(of.FullPath(), tstruct)
 	if renderErr != nil {
 		return "", renderErr
 	}

-	return buffer.String(), nil
+	if !rendered.WriteFile {
+		// abort() was called in the template: nothing would be written to disk.
+		// Include any content rendered before the abort() call for debugging.
+		return rendered.Files[0].Buffer.String() + "Aborted\n", nil
+	}
+
+	// Single output file with no file() calls: return content as-is for backward
+	// compatibility. The default slot has Name == ""; named entries always have a
+	// non-empty Name regardless of how many there are.
+	if len(rendered.Files) == 1 && rendered.Files[0].Name == "" {
+		if rendered.Files[0].IsSymlink {
+			return "Symlink: " + rendered.Files[0].Target + "\n", nil
+		}
+		return rendered.Files[0].Buffer.String(), nil
+	}
+	// One or more file() calls: emit Filename: / Symlink: headers for each named
+	// entry. Skip the default slot (Name == ""); pre-file() content in it is
+	// for RenderTemplateFile callers, not serialized here.
+	var combined strings.Builder
+	for _, f := range rendered.Files {
+		if f.Name == "" {
+			continue
+		}
+		combined.WriteString("Filename: ")
+		combined.WriteString(f.Name)
+		combined.WriteString("\n")
+		if f.IsSymlink {
+			combined.WriteString("Symlink: ")
+			combined.WriteString(f.Target)
+			combined.WriteString("\n")
+		} else {
+			combined.WriteString(f.Buffer.String())
+		}
+	}
+	return combined.String(), nil
 }

 func NewOverlayFile(name string, path string, renderNodeName string) (*OverlayFile, error) {
--- a/internal/pkg/warewulfd/api/overlay_test.go
+++ b/internal/pkg/warewulfd/api/overlay_test.go
@@ -18,6 +18,29 @@ import (
 const sampleTemplate = `{{ if .Tags.email }}eMail: {{ .Tags.email }}{{else}} noMail{{- end }}
 `

+const multiFileTemplate = `{{- range $name := list "alpha" "beta" }}
+{{- file $name -}}
+content of {{ $name }}
+{{ end -}}`
+
+const abortTemplate = `{{- abort -}}`
+
+const abortWithContentTemplate = `some content
+{{- abort -}}`
+
+const symlinkTemplate = `{{- softlink "/usr/share/zoneinfo/UTC" -}}`
+
+const multiSymlinkTemplate = `{{- file "link1" -}}
+{{- softlink "/target1" -}}
+{{- file "link2" -}}
+{{- softlink "/target2" -}}`
+
+const sampleNodesConf = `
+nodeprofiles: {}
+nodes:
+  node1: {}
+`
+
 var overlayTests = []struct {
 	name          string
 	initFiles     map[string]string
@@ -106,6 +129,96 @@ var overlayTests = []struct {
 		},
 		response: `{"test":{"files":null, "site":true},"testoverlay":{"files":["/email.ww"], "site":true}}`,
 	},
+	{
+		name: "render multi-file overlay template",
+		initFiles: map[string]string{
+			"/usr/share/warewulf/overlays/multioverlay/multi.ww": multiFileTemplate,
+			"/etc/warewulf/nodes.conf":                           sampleNodesConf,
+		},
+		request: func(serverURL string) (*http.Request, error) {
+			return http.NewRequest(http.MethodGet, serverURL+"/api/overlays/multioverlay/file?path=multi.ww&render=node1", nil)
+		},
+		response: `{
+			"overlay": "multioverlay",
+			"path": "multi.ww",
+			"contents": "Filename: alpha\ncontent of alpha\nFilename: beta\ncontent of beta\n",
+			"perms": "<<PRESENCE>>",
+			"uid": "<<PRESENCE>>",
+			"gid": "<<PRESENCE>>"
+		}`,
+	},
+	{
+		name: "render aborted template",
+		initFiles: map[string]string{
+			"/usr/share/warewulf/overlays/multioverlay/abort.ww": abortTemplate,
+			"/etc/warewulf/nodes.conf":                           sampleNodesConf,
+		},
+		request: func(serverURL string) (*http.Request, error) {
+			return http.NewRequest(http.MethodGet, serverURL+"/api/overlays/multioverlay/file?path=abort.ww&render=node1", nil)
+		},
+		response: `{
+			"overlay": "multioverlay",
+			"path": "abort.ww",
+			"contents": "Aborted\n",
+			"perms": "<<PRESENCE>>",
+			"uid": "<<PRESENCE>>",
+			"gid": "<<PRESENCE>>"
+		}`,
+	},
+	{
+		name: "render aborted template with pre-abort content",
+		initFiles: map[string]string{
+			"/usr/share/warewulf/overlays/multioverlay/abort-content.ww": abortWithContentTemplate,
+			"/etc/warewulf/nodes.conf":                                   sampleNodesConf,
+		},
+		request: func(serverURL string) (*http.Request, error) {
+			return http.NewRequest(http.MethodGet, serverURL+"/api/overlays/multioverlay/file?path=abort-content.ww&render=node1", nil)
+		},
+		response: `{
+			"overlay": "multioverlay",
+			"path": "abort-content.ww",
+			"contents": "some contentAborted\n",
+			"perms": "<<PRESENCE>>",
+			"uid": "<<PRESENCE>>",
+			"gid": "<<PRESENCE>>"
+		}`,
+	},
+	{
+		name: "render single-file symlink template",
+		initFiles: map[string]string{
+			"/usr/share/warewulf/overlays/multioverlay/symlink.ww": symlinkTemplate,
+			"/etc/warewulf/nodes.conf":                             sampleNodesConf,
+		},
+		request: func(serverURL string) (*http.Request, error) {
+			return http.NewRequest(http.MethodGet, serverURL+"/api/overlays/multioverlay/file?path=symlink.ww&render=node1", nil)
+		},
+		response: `{
+			"overlay": "multioverlay",
+			"path": "symlink.ww",
+			"contents": "Symlink: /usr/share/zoneinfo/UTC\n",
+			"perms": "<<PRESENCE>>",
+			"uid": "<<PRESENCE>>",
+			"gid": "<<PRESENCE>>"
+		}`,
+	},
+	{
+		name: "render multi-file symlink template",
+		initFiles: map[string]string{
+			"/usr/share/warewulf/overlays/multioverlay/multi-symlink.ww": multiSymlinkTemplate,
+			"/etc/warewulf/nodes.conf":                                   sampleNodesConf,
+		},
+		request: func(serverURL string) (*http.Request, error) {
+			return http.NewRequest(http.MethodGet, serverURL+"/api/overlays/multioverlay/file?path=multi-symlink.ww&render=node1", nil)
+		},
+		response: `{
+			"overlay": "multioverlay",
+			"path": "multi-symlink.ww",
+			"contents": "Filename: link1\nSymlink: /target1\nFilename: link2\nSymlink: /target2\n",
+			"perms": "<<PRESENCE>>",
+			"uid": "<<PRESENCE>>",
+			"gid": "<<PRESENCE>>"
+		}`,
+	},
 	{
 		name: "delete overlay file",
 		initFiles: map[string]string{