Initial implementation of post rendering over gmi

1 files changed, 134 insertions, 0 deletions

diff --git a/src/gmi/tpl.go b/src/gmi/tpl.go
new file mode 100644
index 0000000..7aa1a2f
--- /dev/null
+++ b/src/gmi/tpl.go
@@ -0,0 +1,134 @@
+package gmi
+
+import (
+	"bytes"
+	"context"
+	"embed"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/url"
+	"strconv"
+	"strings"
+	"text/template"
+
+	"git.sr.ht/~adnano/go-gemini"
+	"github.com/mediocregopher/blog.mediocregopher.com/srv/post"
+	"github.com/mediocregopher/mediocre-go-lib/v2/mctx"
+)
+
+//go:embed tpl
+var tplFS embed.FS
+
+type rendererGetPostsRes struct {
+	Posts   []post.StoredPost
+	HasMore bool
+}
+
+type renderer struct {
+	url       *url.URL
+	postStore post.Store
+}
+
+func (r renderer) GetPosts(page, count int) (rendererGetPostsRes, error) {
+	posts, hasMore, err := r.postStore.Get(page, count)
+	return rendererGetPostsRes{posts, hasMore}, err
+}
+
+func (r renderer) GetPostByID(id string) (post.StoredPost, error) {
+	p, err := r.postStore.GetByID(id)
+	if err != nil {
+		return post.StoredPost{}, fmt.Errorf("fetching post %q: %w", id, err)
+	}
+	return p, nil
+}
+
+func (r renderer) GetQueryValue(key, def string) string {
+	v := r.url.Query().Get(key)
+	if v == "" {
+		v = def
+	}
+	return v
+}
+
+func (r renderer) GetQueryIntValue(key string, def int) (int, error) {
+	vStr := r.GetQueryValue(key, strconv.Itoa(def))
+	return strconv.Atoi(vStr)
+}
+
+func (r renderer) Add(a, b int) int { return a + b }
+
+func (a *api) tplHandler() (gemini.Handler, error) {
+
+	allTpls := template.New("")
+
+	err := fs.WalkDir(tplFS, "tpl", func(path string, d fs.DirEntry, err error) error {
+
+		if err != nil {
+			return err
+		}
+
+		if d.IsDir() {
+			return nil
+		}
+
+		body, err := fs.ReadFile(tplFS, path)
+		if err != nil {
+			panic(err)
+		}
+
+		name := strings.TrimPrefix(path, "tpl/")
+
+		allTpls, err = allTpls.New(name).Parse(string(body))
+		if err != nil {
+			return fmt.Errorf("parsing %q as template: %w", path, err)
+		}
+
+		return nil
+	})
+
+	if err != nil {
+		return nil, fmt.Errorf("parsing templates: %w", err)
+	}
+
+	return gemini.HandlerFunc(func(
+		ctx context.Context,
+		rw gemini.ResponseWriter,
+		r *gemini.Request,
+	) {
+
+		if strings.HasSuffix(r.URL.Path, "/") {
+			r.URL.Path += "index.gmi"
+		}
+
+		tplPath := strings.TrimPrefix(r.URL.Path, "/")
+
+		ctx = mctx.Annotate(ctx,
+			"url", r.URL,
+			"tplPath", tplPath,
+		)
+
+		tpl := allTpls.Lookup(tplPath)
+
+		if tpl == nil {
+			a.params.Logger.WarnString(ctx, "page not found")
+			rw.WriteHeader(gemini.StatusNotFound, "Page not found, sorry!")
+			return
+		}
+
+		buf := new(bytes.Buffer)
+
+		err := tpl.Execute(buf, renderer{
+			url:       r.URL,
+			postStore: a.params.PostStore,
+		})
+
+		if err != nil {
+			a.params.Logger.Error(ctx, "rendering error", err)
+			rw.WriteHeader(gemini.StatusTemporaryFailure, err.Error())
+			return
+		}
+
+		io.Copy(rw, buf)
+	}), nil
+}