Make templates optional

dir.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"log"
@@ -89,22 +90,26 @@ func (d *Dir) Process(cfg *Config, task *Task) error {
 	if task.TemplateExt != "" {
 		// Create index
 		if d.index != nil {
-			var b strings.Builder
-			tmpl := cfg.Templates.FindTemplate(d.Path, "index"+task.TemplateExt)
-			if err := tmpl.Execute(&b, d); err != nil {
-				return err
+			tmpl, ok := cfg.Templates.FindTemplate(d.Path, "index"+task.TemplateExt)
+			if ok {
+				var b strings.Builder
+				if err := tmpl.Execute(&b, d); err != nil {
+					return err
+				}
+				d.index.Content = b.String()
 			}
-			d.index.Content = b.String()
 		}
 
 		// Process pages
 		for i := range d.Pages {
 			var b strings.Builder
-			tmpl := cfg.Templates.FindTemplate(d.Path, "page"+task.TemplateExt)
-			if err := tmpl.Execute(&b, d.Pages[i]); err != nil {
-				return err
+			tmpl, ok := cfg.Templates.FindTemplate(d.Path, "page"+task.TemplateExt)
+			if ok {
+				if err := tmpl.Execute(&b, d.Pages[i]); err != nil {
+					return err
+				}
+				d.Pages[i].Content = b.String()
 			}
-			d.Pages[i].Content = b.String()
 		}
 	}
 
@@ -125,11 +130,15 @@ func (d *Dir) Process(cfg *Config, task *Task) error {
 			Updated: time.Now(),
 			Entries: d.Pages,
 		}
-		tmpl := cfg.Templates.FindTemplate(d.Path, "atom.xml")
-		if err := tmpl.Execute(&b, feed); err != nil {
-			return err
+		tmpl, ok := cfg.Templates.FindTemplate(d.Path, "atom.xml")
+		if ok {
+			if err := tmpl.Execute(&b, feed); err != nil {
+				return err
+			}
+			d.feed = b.Bytes()
+		} else {
+			fmt.Printf("Warning: failed to generate feed %q: missing template \"atom.xml\"\n", title)
 		}
-		d.feed = b.Bytes()
 	}
 
 	// Process subdirectories

templates.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"io/ioutil"
-	"log"
 	"os"
 	pathpkg "path"
 	"path/filepath"
@@ -56,15 +55,15 @@ func (t *Templates) Load(dir string) error {
 	})
 }
 
-// FindTemplate returns a template for the given path, or the default template if it does not exist.
-func (t *Templates) FindTemplate(path string, tmpl string) *template.Template {
+// FindTemplate returns the template for the given path.
+func (t *Templates) FindTemplate(path string, tmpl string) (*template.Template, bool) {
 	tmplPath := pathpkg.Join(path, tmpl)
 	if t, ok := t.tmpls[tmplPath]; ok {
-		return t
+		return t, true
 	}
 	if t, ok := t.tmpls[pathpkg.Join("/_default", tmpl)]; ok {
-		return t
+		return t, true
 	}
-	log.Fatalf("failed to find template %q", tmpl)
-	return nil
+	// Failed to find template
+	return nil, false
 }