tasks: add tasks.feeds support

Every task can now have a [[tasks.feeds]] entry to generate one or more feeds.
It must have the following arguments:

[[tasks.feeds]]
input_dir = ""
title = "Example feed"
template = "atom.xml"
output = "atom.xml"

config.toml

@@ -1,9 +1,6 @@
 title = "Example website"
 urls = ["gemini://example.com"]
 
-[feeds]
-"/" = "Example feed"
-
 [permalinks]
 "/" = "/{{ .Date.Format `2006/01/02` }}/{{ path.Base .Permalink }}/"
 
@@ -13,3 +10,9 @@ output = ".gmi"
 template = ".gmi"
 static_dir = "static"
 output_dir = "public"
+
+[[tasks.feeds]]
+input_dir = ""
+title = "Example feed"
+template = "atom.xml"
+output = "atom.xml"

dir.go

@@ -22,7 +22,9 @@ type Dir struct {
 	Pages      []*Page
 	Dirs       []*Dir
 	index      *Page             // The index page.
-	feed      []byte // Atom feed.
+	feed       []byte            // Atom feed (deprecated)
+	extraFiles map[string][]byte // Atom/RSS feeds
+	path       string            // relative to the content dir
 }
 
 // Page represents a page.
@@ -57,7 +59,7 @@ func (d *Dir) _read(srcDir, path string, task *Task, cfg *Site) error {
 				continue
 			}
 			// Gather directory data
-			dir := &Dir{Permalink: "/" + path + "/"}
+			dir := &Dir{Permalink: "/" + path + "/", path: path}
 			if err := dir._read(srcDir, path, task, cfg); err != nil {
 				return err
 			}
@@ -151,6 +153,21 @@ func (d *Dir) _read(srcDir, path string, task *Task, cfg *Site) error {
 
 // process processes the directory's contents.
 func (d *Dir) process(cfg *Site, task *Task) error {
+	// build feeds
+	// this must happen before the page processing
+	// to have an unprocessed Page.Content
+	// 192: d.Pages[i].Content = b.String()
+	for _, feed := range task.Feeds {
+		if d.path != feed.InputDir {
+			continue
+		}
+		b, err := d.buildFeed(cfg, feed)
+		if err != nil {
+			return err
+		}
+		d.addExtraFile(feed.Output, b)
+	}
+
 	if task.TemplateExt != "" {
 		// Create index
 		if d.index != nil {
@@ -214,6 +231,39 @@ func (d *Dir) process(cfg *Site, task *Task) error {
 	return nil
 }
 
+// buildFeed build the feed of the directory
+func (d Dir) buildFeed(cfg *Site, feed Feed) ([]byte, error) {
+	tmpl, ok := cfg.templates.FindTemplate(d.Permalink, feed.Template)
+	if !ok {
+		return nil, fmt.Errorf("missing feed template %q to generate %q", feed.Template, feed.Title)
+	}
+
+	var b bytes.Buffer
+	data := struct {
+		Title     string    // Feed title.
+		Permalink string    // Feed permalink.
+		Updated   time.Time // Last updated time.
+		Pages     []*Page   // Feed pages.
+	}{
+		Title:     feed.Title,
+		Permalink: d.Permalink,
+		Updated:   time.Now(),
+		Pages:     d.Pages,
+	}
+	if err := tmpl.Execute(&b, data); err != nil {
+		return nil, err
+	}
+	return b.Bytes(), nil
+}
+
+func (d *Dir) addExtraFile(name string, content []byte) {
+	if d.extraFiles == nil {
+		d.extraFiles = map[string][]byte{name: content}
+	} else {
+		d.extraFiles[name] = content
+	}
+}
+
 // write writes the directory's contents to the provided destination path.
 func (d *Dir) write(dstDir string, task *Task) error {
 	dirPath := pathpkg.Join(dstDir, d.Permalink)
@@ -255,6 +305,15 @@ func (d *Dir) write(dstDir string, task *Task) error {
 		}
 	}
 
+	// Write feeds
+	for name, content := range d.extraFiles {
+		dstPath := pathpkg.Join(dstDir, name)
+		os.MkdirAll(dirPath, 0755)
+		if err := os.WriteFile(dstPath, content, 0644); err != nil {
+			return err
+		}
+	}
+
 	// Write subdirectories
 	for _, dir := range d.Dirs {
 		dir.write(dstDir, task)

docs/kiln.1.scd

@@ -187,20 +187,31 @@ site URLs may be specified for sites that are available at multiple locations.
 
 ## FEEDS
 
-Feeds can be specified in the [feeds] table of the configuration file. Keys
-denote the path to the feed directory and values denote the title of the feed.
-
-Feeds are written to the output directory plus the feed directory plus
-"atom.xml".
+Feeds can be specified in [[tasks.feeds]] for every task needing them.
 
 Example feed configuration:
 
 	```
 	# This will generate a feed which will be written to public/blog/atom.xml
-	[feeds]
-	"/blog/" = "My blog"
+	[[tasks.feeds]]
+	input_dir = "blog"
+	title = "My Blog"
+	template = "atom.xml"
+	output = "blog/atom.xml"
 	```
 
+*input_dir*
+	the content folder for which the feed will be generated
+
+*title*
+	the title of the feed, accessible via {{ .Title }} in the template
+
+*template*
+	the template to use for the feed
+
+*output*
+	the absolute path for the rendered feed
+
 ## PERMALINKS
 
 Permalinks can be used to rewrite page paths. Permalinks are specified in the

main.go

@@ -71,7 +71,7 @@ func (site *Site) run() error {
 
 func (s *Site) runTask(task *Task) error {
 	// Read content
-	s.root = &Dir{Permalink: "/"}
+	s.root = &Dir{Permalink: "/", path: ""}
 	if err := s.root.read("content", task, s); err != nil {
 		return err
 	}

site.go

@@ -2,7 +2,10 @@ package main
 
 import (
 	"fmt"
+	"log"
 	"os"
+	"path"
+	"strings"
 	"text/template"
 
 	"github.com/pelletier/go-toml"
@@ -31,6 +34,14 @@ type Task struct {
 	StaticDir   string            `toml:"static_dir"`  // static file directory
 	OutputDir   string            `toml:"output_dir"`  // output directory
 	UglyURLs    bool              `toml:"ugly_urls"`   // whether to use ugly URLs
+	Feeds       []Feed            `toml:"feeds"`
+}
+
+type Feed struct {
+	InputDir string `toml:"input_dir"`
+	Title    string `toml:"title"`
+	Template string `toml:"template"`
+	Output   string `toml:"output"`
 }
 
 func (t *Task) Match(ext string) bool {
@@ -80,6 +91,30 @@ func LoadSite(config string) (*Site, error) {
 		return nil, err
 	}
 
+	// deprecate [feeds]
+	if len(site.Feeds) > 0 {
+		log.Println("The [feeds] configuration is deprecated")
+		for _, task := range site.Tasks {
+			if len(task.Feeds) > 0 {
+				log.Println("and can't be used along [[tasks.feeds]]")
+				return nil, fmt.Errorf("please remove (or rename) the [feeds] category")
+			}
+		}
+		log.Println("Please replace it with [[tasks.feeds]] in every task needing feeds:")
+		for permalink, title := range site.Feeds {
+			dir := strings.Trim(permalink, "/")
+			output := path.Join(dir, "atom.xml")
+			fmt.Fprintf(log.Writer(), `[[tasks.feeds]]
+input_dir = %q
+title = %q
+template = "atom.xml"
+output = %q
+
+`, dir, title, output)
+		}
+		log.Println("You will also need to change .Entries to .Pages in \"atom.xml\"")
+	}
+
 	return site, nil
 }
 

templates/_default/atom.xml

@@ -4,7 +4,7 @@
 <title>{{ .Title }}</title>
 <updated>{{ .Updated.Format "2006-01-02T15:04:05Z07:00" }}</updated>
 <link href="{{ index site.URLs 0 | safeURL }}{{ .Permalink }}" rel="alternate"/>
-{{ range .Entries }}<entry>
+{{ range .Pages }}<entry>
 	<id>{{ index site.URLs 0 }}{{ .Permalink }}</id>
 	<title>{{ .Title }}</title>
 	<updated>{{ .Date.Format "2006-01-02T15:04:05Z07:00" }}</updated>