hugolib: Wrap pageOutput create in sync.Once

3 files changed, 31 insertions, 6 deletions

diff --git a/hugolib/page.go b/hugolib/page.go
index 7dfc49faa..84dfa2f43 100644
--- a/hugolib/page.go
+++ b/hugolib/page.go
@@ -244,6 +244,7 @@ type pageInit struct {
 	languageInit        sync.Once
 	pageMenusInit       sync.Once
 	pageMetaInit        sync.Once
+	pageOutputInit      sync.Once
 	plainInit           sync.Once
 	plainWordsInit      sync.Once
 	renderingConfigInit sync.Once
diff --git a/hugolib/page_output.go b/hugolib/page_output.go
index 20d051e8c..542c50e62 100644
--- a/hugolib/page_output.go
+++ b/hugolib/page_output.go
@@ -108,6 +108,21 @@ func (p *PageOutput) Render(layout ...string) template.HTML {
 
 // TODO(bep) output
 func (p *Page) Render(layout ...string) template.HTML {
+	p.pageOutputInit.Do(func() {
+		// If Render is called in a range loop, the page output isn't available.
+		// So, create one.
+		outFormat := p.outputFormats[0]
+		pageOutput, err := newPageOutput(p, true, outFormat)
+
+		if err != nil {
+			p.s.Log.ERROR.Printf("Failed to create output page for type %q for page %q: %s", outFormat.Name, p, err)
+			return
+		}
+
+		p.mainPageOutput = pageOutput
+
+	})
+
 	return p.mainPageOutput.Render(layout...)
 }
 
diff --git a/hugolib/site_render.go b/hugolib/site_render.go
index 5f46bd0c9..330601013 100644
--- a/hugolib/site_render.go
+++ b/hugolib/site_render.go
@@ -60,22 +60,31 @@ func (s *Site) renderPages() error {
 
 func pageRenderer(s *Site, pages <-chan *Page, results chan<- error, wg *sync.WaitGroup) {
 	defer wg.Done()
-	var mainPageOutput *PageOutput
 
 	for page := range pages {
 
 		for i, outFormat := range page.outputFormats {
 
-			pageOutput, err := newPageOutput(page, i > 0, outFormat)
+			var (
+				pageOutput *PageOutput
+				err        error
+			)
+
+			if i == 0 {
+				page.pageOutputInit.Do(func() {
+					var po *PageOutput
+					po, err = newPageOutput(page, false, outFormat)
+					page.mainPageOutput = po
+				})
+				pageOutput = page.mainPageOutput
+			} else {
+				pageOutput, err = newPageOutput(page, true, outFormat)
+			}
 
 			if err != nil {
 				s.Log.ERROR.Printf("Failed to create output page for type %q for page %q: %s", outFormat.Name, page, err)
 				continue
 			}
-			if i == 0 {
-				mainPageOutput = pageOutput
-			}
-			page.mainPageOutput = mainPageOutput
 
 			var layouts []string