Added RSS and JSON feeds

providers/sitebuilder/builder.go

@@ -6,11 +6,13 @@ import (
 	"fmt"
 	"html/template"
 	"io"
+	"iter"
 	"os"
 	"path/filepath"
-	"sort"
 	"strings"
+	"time"
 
+	"github.com/gopherlibs/feedhub/feedhub"
 	"golang.org/x/sync/errgroup"
 	"lmika.dev/lmika/weiro/models"
 	"lmika.dev/lmika/weiro/models/pubmodel"
@@ -47,10 +49,14 @@ func (b *Builder) BuildSite(outDir string) error {
 		return err
 	}
 
-	eg := errgroup.Group{}
+	eg, ctx := errgroup.WithContext(context.Background())
 
 	eg.Go(func() error {
-		for _, post := range b.site.Posts {
+		for mp := range b.site.PostIter(ctx) {
+			post, err := mp.Get()
+			if err != nil {
+				return err
+			}
 			if err := b.writePost(buildCtx, post); err != nil {
 				return err
 			}
@@ -59,7 +65,14 @@ func (b *Builder) BuildSite(outDir string) error {
 	})
 
 	eg.Go(func() error {
-		if err := b.renderPostList(buildCtx, b.site.Posts); err != nil {
+		if err := b.renderPostList(buildCtx, b.site.PostIter(ctx)); err != nil {
+			return err
+		}
+		return nil
+	})
+
+	eg.Go(func() error {
+		if err := b.renderFeeds(buildCtx, b.site.PostIter(ctx)); err != nil {
 			return err
 		}
 		return nil
@@ -79,14 +92,16 @@ func (b *Builder) BuildSite(outDir string) error {
 	return nil
 }
 
-func (b *Builder) renderPostList(ctx buildContext, postList []*models.Post) error {
+func (b *Builder) renderPostList(ctx buildContext, postIter iter.Seq[models.Maybe[*models.Post]]) error {
 	// TODO: paging
-	postCopy := make([]*models.Post, len(postList))
-	copy(postCopy, postList)
-
-	sort.Slice(postCopy, func(i, j int) bool {
-		return postCopy[i].PublishedAt.After(postCopy[j].PublishedAt)
-	})
+	postCopy := make([]*models.Post, 0)
+	for mp := range postIter {
+		post, err := mp.Get()
+		if err != nil {
+			return err
+		}
+		postCopy = append(postCopy, post)
+	}
 
 	pl := postListData{
 		commonData: commonData{Site: b.site},
@@ -104,6 +119,68 @@ func (b *Builder) renderPostList(ctx buildContext, postList []*models.Post) erro
 	})
 }
 
+func (b *Builder) renderFeeds(ctx buildContext, postIter iter.Seq[models.Maybe[*models.Post]]) error {
+	now := time.Now()
+	feed := &feedhub.Feed{
+		Title:       b.site.Title,
+		Link:        &feedhub.Link{Href: b.site.BaseURL},
+		Description: b.site.Tagline,
+		// TO FIX: Author
+		Created: now,
+	}
+
+	items := 0
+	for mp := range postIter {
+		post, err := mp.Get()
+		if err != nil {
+			return fmt.Errorf("failed to get post: %w", err)
+		}
+
+		renderedPost, err := b.renderPost(post)
+		if err != nil {
+			return err
+		}
+
+		feed.Items = append(feed.Items, &feedhub.Item{
+			Id:      filepath.Join(b.site.BaseURL, post.GUID),
+			Title:   post.Title,
+			Link:    &feedhub.Link{Href: renderedPost.PostURL},
+			Content: string(renderedPost.HTML),
+			// TO FIX: Created should be first published
+			Created: post.PublishedAt,
+			Updated: post.PublishedAt,
+		})
+
+		items++
+		if items >= b.opts.FeedItems {
+			break
+		}
+	}
+
+	if err := b.createAtPath(ctx, "/feed.xml", func(f io.Writer) error {
+		rss, err := feed.ToRss()
+		if err != nil {
+			return fmt.Errorf("failed to convert feed to RSS: %w", err)
+		}
+		_, err = io.WriteString(f, rss)
+		return err
+	}); err != nil {
+		return err
+	}
+
+	if err := b.createAtPath(ctx, "/feed.json", func(f io.Writer) error {
+		rss, err := feed.ToJSON()
+		if err != nil {
+			return fmt.Errorf("failed to convert feed to JSON feed: %w", err)
+		}
+		_, err = io.WriteString(f, rss)
+		return err
+	}); err != nil {
+		return err
+	}
+	return nil
+}
+
 func (b *Builder) renderPost(post *models.Post) (postSingleData, error) {
 	postPath := post.Slug
 	if b.opts.BasePosts != "" {
@@ -115,10 +192,13 @@ func (b *Builder) renderPost(post *models.Post) (postSingleData, error) {
 		return postSingleData{}, fmt.Errorf("failed to write post %s: %w", post.Slug, err)
 	}
 
+	postURL := strings.TrimSuffix(b.site.BaseURL, "/") + "/" + strings.TrimPrefix(postPath, "/")
+
 	return postSingleData{
 		commonData: commonData{Site: b.site},
 		Path:       postPath,
 		Post:       post,
+		PostURL:    postURL,
 		HTML:       template.HTML(md.String()),
 	}, nil
 }

providers/sitebuilder/tmpls.go

@@ -29,6 +29,9 @@ type Options struct {
 	// TemplatesFS provides the raw templates for rendering the site.
 	TemplatesFS fs.FS
 
+	// FeedItems holds the number of posts to show in the feed.
+	FeedItems int
+
 	RenderTZ *time.Location
 }
 
@@ -38,9 +41,10 @@ type commonData struct {
 
 type postSingleData struct {
 	commonData
-	Post *models.Post
-	HTML template.HTML
-	Path string
+	Post    *models.Post
+	HTML    template.HTML
+	Path    string
+	PostURL string
 }
 
 type postListData struct {