diff options
Diffstat (limited to 'srv/src/api/render.go')
-rw-r--r-- | srv/src/api/render.go | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/srv/src/api/render.go b/srv/src/api/render.go new file mode 100644 index 0000000..b2ca3c8 --- /dev/null +++ b/srv/src/api/render.go @@ -0,0 +1,161 @@ +package api + +import ( + "embed" + "errors" + "fmt" + "html/template" + "io/fs" + "net/http" + "path/filepath" + "strings" + + "github.com/gomarkdown/markdown" + "github.com/gomarkdown/markdown/html" + "github.com/gomarkdown/markdown/parser" + "github.com/mediocregopher/blog.mediocregopher.com/srv/api/apiutil" + "github.com/mediocregopher/blog.mediocregopher.com/srv/post" +) + +//go:embed tpl +var tplFS embed.FS + +func mustParseTpl(name string) *template.Template { + + mustRead := func(fileName string) string { + path := filepath.Join("tpl", fileName) + + b, err := fs.ReadFile(tplFS, path) + if err != nil { + panic(fmt.Errorf("reading file %q from tplFS: %w", path, err)) + } + + return string(b) + } + + tpl := template.Must(template.New("").Parse(mustRead(name))) + tpl = template.Must(tpl.New("base.html").Parse(mustRead("base.html"))) + + return tpl +} + +func (a *api) renderIndexHandler() http.Handler { + + tpl := mustParseTpl("index.html") + const pageCount = 20 + + return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { + + if path := r.URL.Path; !strings.HasSuffix(path, "/") && filepath.Base(path) != "index.html" { + http.Error(rw, "Page not found", 404) + return + } + + page, err := apiutil.StrToInt(r.FormValue("p"), 0) + if err != nil { + apiutil.BadRequest( + rw, r, fmt.Errorf("invalid page number: %w", err), + ) + return + } + + posts, _, err := a.params.PostStore.Get(page, pageCount) + if err != nil { + apiutil.InternalServerError( + rw, r, fmt.Errorf("fetching page %d of posts: %w", page, err), + ) + return + } + + tplData := struct { + Posts []post.StoredPost + }{ + Posts: posts, + } + + if err := tpl.Execute(rw, tplData); err != nil { + apiutil.InternalServerError( + rw, r, fmt.Errorf("rendering index: %w", err), + ) + return + } + }) +} + +func (a *api) renderPostHandler() http.Handler { + + tpl := mustParseTpl("post.html") + + return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { + + id := strings.TrimSuffix(filepath.Base(r.URL.Path), ".html") + + storedPost, err := a.params.PostStore.GetByID(id) + + if errors.Is(err, post.ErrPostNotFound) { + http.Error(rw, "Post not found", 404) + return + } else if err != nil { + apiutil.InternalServerError( + rw, r, fmt.Errorf("fetching post with id %q: %w", id, err), + ) + return + } + + parserExt := parser.CommonExtensions | parser.AutoHeadingIDs + parser := parser.NewWithExtensions(parserExt) + + htmlFlags := html.CommonFlags | html.HrefTargetBlank + htmlRenderer := html.NewRenderer(html.RendererOptions{Flags: htmlFlags}) + + renderedBody := markdown.ToHTML([]byte(storedPost.Body), parser, htmlRenderer) + + tplData := struct { + post.StoredPost + SeriesPrevious, SeriesNext *post.StoredPost + Body template.HTML + }{ + StoredPost: storedPost, + Body: template.HTML(renderedBody), + } + + if series := storedPost.Series; series != "" { + + seriesPosts, err := a.params.PostStore.GetBySeries(series) + if err != nil { + apiutil.InternalServerError( + rw, r, + fmt.Errorf("fetching posts for series %q: %w", series, err), + ) + return + } + + var foundThis bool + + for i := range seriesPosts { + + seriesPost := seriesPosts[i] + + if seriesPost.ID == storedPost.ID { + foundThis = true + continue + } + + if !foundThis { + tplData.SeriesPrevious = &seriesPost + continue + } + + tplData.SeriesNext = &seriesPost + break + } + } + + if err := tpl.Execute(rw, tplData); err != nil { + apiutil.InternalServerError( + rw, r, fmt.Errorf("rendering post with id %q: %w", id, err), + ) + return + } + }) +} |