| 1 | package todo |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "embed" |
| 6 | "html/template" |
| 7 | "net/http" |
| 8 | "strconv" |
| 9 | |
| 10 | "amadan.net/rastrillo/rastrillo" |
| 11 | ) |
| 12 | |
| 13 | //go:embed templates static |
| 14 | var appFS embed.FS |
| 15 | |
| 16 | // assets fingerprints static/: {{asset "static/index.css"}} returns a |
| 17 | // content-hashed URL served immutable-cacheable, and the bare name |
| 18 | // (/static/index.css) is served too, never long-cached. |
| 19 | var assets = rastrillo.NewAssets(appFS) |
| 20 | |
| 21 | var templates = template.Must(template.New(""). |
| 22 | Funcs(template.FuncMap{ |
| 23 | "asset": assets.Path, |
| 24 | "plural": func(n int) string { |
| 25 | if n == 1 { |
| 26 | return "item" |
| 27 | } |
| 28 | return "items" |
| 29 | }, |
| 30 | }). |
| 31 | ParseFS(appFS, "templates/*.html")) |
| 32 | |
| 33 | // render executes a template into a buffer before anything touches the |
| 34 | // wire, so a template error becomes a clean 500 and the response |
| 35 | // carries an exact Content-Length. |
| 36 | func render(w http.ResponseWriter, name string, data any) { |
| 37 | renderStatus(w, http.StatusOK, name, data) |
| 38 | } |
| 39 | |
| 40 | func renderStatus(w http.ResponseWriter, status int, name string, data any) { |
| 41 | var buf bytes.Buffer |
| 42 | if err := templates.ExecuteTemplate(&buf, name, data); err != nil { |
| 43 | http.Error(w, "something went wrong", http.StatusInternalServerError) |
| 44 | return |
| 45 | } |
| 46 | h := w.Header() |
| 47 | h.Set("Content-Type", "text/html; charset=utf-8") |
| 48 | h.Set("Content-Length", strconv.Itoa(buf.Len())) |
| 49 | w.WriteHeader(status) |
| 50 | buf.WriteTo(w) |
| 51 | } |
| 52 | |
| 53 | // ErrorPage is the rastrillo.ErrorPageFunc Options.ErrorPage points at, |
| 54 | // so a panic gets the same page a handled failure does: TodoMVC's frame |
| 55 | // with the status and, for a 500, the ref the log line carries. |
| 56 | func ErrorPage(w http.ResponseWriter, r *http.Request, status int, ref string) { |
| 57 | title := http.StatusText(status) |
| 58 | if status == http.StatusInternalServerError { |
| 59 | title = "Something went wrong on our side" |
| 60 | } |
| 61 | renderStatus(w, status, "errors", map[string]any{"Title": title, "Ref": ref}) |
| 62 | } |
| 63 | |
| 64 | func errorPage(w http.ResponseWriter, status int, title string) { |
| 65 | renderStatus(w, status, "errors", map[string]any{"Title": title}) |
| 66 | } |
| 67 | |
amadan