dockerify

Signed-off-by: Naman Sood <mail@nsood.in>

cmd/prose/post.go

@@ -0,0 +1,191 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"sort"
+	"strings"
+
+	"github.com/aymerick/raymond"
+	"github.com/mitchellh/mapstructure"
+	"github.com/yuin/goldmark"
+	emoji "github.com/yuin/goldmark-emoji"
+	highlighting "github.com/yuin/goldmark-highlighting"
+	meta "github.com/yuin/goldmark-meta"
+	"github.com/yuin/goldmark/extension"
+	"github.com/yuin/goldmark/parser"
+	"github.com/yuin/goldmark/renderer/html"
+)
+
+// Metadata stores the data about a post that needs to be visible
+// at the home page.
+type Metadata struct {
+	Title   string
+	Summary string
+	Time    int64 // unix timestamp
+}
+
+// Post stores the contents of a blog post.
+type Post struct {
+	Slug     string
+	Metadata Metadata
+	Contents string
+	Image    []byte
+}
+
+func newPost(slug string) (*Post, error) {
+	data, err := os.ReadFile("posts/" + slug + ".md")
+	if err != nil {
+		return nil, fmt.Errorf("could not read file: %s", err)
+	}
+
+	md := goldmark.New(
+		goldmark.WithExtensions(
+			extension.Linkify,
+			extension.Strikethrough,
+			extension.Typographer,
+			extension.Footnote,
+			meta.Meta,
+			highlighting.Highlighting,
+			emoji.New(emoji.WithRenderingMethod(emoji.Unicode)),
+		),
+		goldmark.WithRendererOptions(
+			html.WithUnsafe(),
+		),
+	)
+	var converted bytes.Buffer
+	ctx := parser.NewContext()
+	err = md.Convert(data, &converted, parser.WithContext(ctx))
+	if err != nil {
+		return nil, fmt.Errorf("could not parse markdown: %s", err)
+	}
+	mdMap, err := meta.TryGet(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("could not parse metadata: %s", err)
+	}
+	var metadata Metadata
+	err = mapstructure.Decode(mdMap, &metadata)
+	if err != nil {
+		return nil, fmt.Errorf("could not destructure metadata: %s", err)
+	}
+
+	post := &Post{
+		Slug:     slug,
+		Metadata: metadata,
+		Contents: converted.String(),
+	}
+
+	url := blogURL + "/" + slug
+	var buf bytes.Buffer
+	err = createImage(post.Metadata.Title, post.Metadata.Summary, url, &buf)
+	if err != nil {
+		return nil, fmt.Errorf("could not create post image: %v", err)
+	}
+	post.Image, err = io.ReadAll(&buf)
+	if err != nil {
+		return nil, err
+	}
+
+	return post, nil
+}
+
+func (p *Post) render(tpl *raymond.Template) (string, error) {
+	return tpl.Exec(p)
+}
+
+func (p *Post) String() string {
+	return p.Slug
+}
+
+type postList []*Post
+
+func newPostList() (postList, error) {
+	files, err := os.ReadDir("posts/")
+	if err != nil {
+		return nil, err
+	}
+
+	pl := make(postList, 0, len(files))
+	for _, f := range files {
+		filename := f.Name()
+
+		if strings.HasSuffix(filename, ".md") {
+			post, err := newPost(strings.TrimSuffix(filename, ".md"))
+			if err != nil {
+				return nil, fmt.Errorf("could not render %s: %s", filename, err)
+			}
+			pl = append(pl, post)
+			log.Printf("Loaded post %s", filename)
+		}
+	}
+	sort.Sort(pl)
+
+	return pl, nil
+}
+
+func insertOrUpdatePost(pl postList, p *Post) postList {
+	for i, post := range pl {
+		if post.Slug == p.Slug {
+			pl[i] = p
+			sort.Sort(pl)
+			return pl
+		}
+	}
+	pl = append(pl, p)
+	sort.Sort(pl)
+	return pl
+}
+
+func removePost(pl postList, slug string) postList {
+	for i, post := range pl {
+		if post.Slug == slug {
+			pl = append(pl[:i], pl[i+1:]...)
+			break
+		}
+	}
+	fmt.Println(pl)
+	return pl
+}
+
+// Len implements sort.Interface
+func (pl postList) Len() int {
+	return len(pl)
+}
+
+// Less implements sort.Interface
+func (pl postList) Less(i, j int) bool {
+	return pl[i].Metadata.Time > pl[j].Metadata.Time
+}
+
+// Swap implements sort.Interface
+func (pl postList) Swap(i, j int) {
+	temp := pl[i]
+	pl[i] = pl[j]
+	pl[j] = temp
+}
+
+func newPostListener(update func(func(postList) postList)) *listener {
+	ln := &listener{
+		folder: "posts/",
+		update: func(file string) error {
+			post, err := newPost(strings.TrimSuffix(file, ".md"))
+			if err != nil {
+				return err
+			}
+			update(func(oldList postList) postList {
+				return insertOrUpdatePost(oldList, post)
+			})
+			return nil
+		},
+		clean: func(file string) error {
+			update(func(oldList postList) postList {
+				return removePost(oldList, strings.TrimSuffix(file, ".md"))
+			})
+			return nil
+		},
+	}
+	return ln
+}