package http import ( "embed" "fmt" "html/template" "io/fs" "net/http" "path/filepath" "strings" "time" "github.com/mediocregopher/blog.mediocregopher.com/srv/http/apiutil" ) //go:embed tpl var tplFS embed.FS func mustReadTplFile(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) } func (a *api) blogURL(path string, abs bool) string { // filepath.Join strips trailing slash, but we want to keep it trailingSlash := strings.HasSuffix(path, "/") res := filepath.Join("/", path) if trailingSlash && res != "/" { res += "/" } if abs { res = a.params.PublicURL.String() + res } return res } func (a *api) postURL(id string, abs bool) string { path := filepath.Join("posts", id) return a.blogURL(path, abs) } func (a *api) editPostURL(id string, abs bool) string { return a.postURL(id, abs) + "?method=edit" } func (a *api) managePostsURL(abs bool) string { return a.blogURL("posts?method=manage", abs) } func (a *api) manageAssetsURL(abs bool) string { return a.blogURL("assets?method=manage", abs) } func (a *api) assetURL(id string, abs bool) string { path := filepath.Join("assets", id) return a.blogURL(path, false) } func (a *api) draftPostURL(id string, abs bool) string { path := filepath.Join("drafts", id) return a.blogURL(path, abs) } func (a *api) editDraftPostURL(id string, abs bool) string { return a.draftPostURL(id, abs) + "?method=edit" } func (a *api) manageDraftPostsURL(abs bool) string { return a.blogURL("drafts", abs) + "?method=manage" } func (a *api) draftsURL(abs bool) string { return a.blogURL("drafts", abs) } func (a *api) tplFuncs() template.FuncMap { return template.FuncMap{ "BlogURL": func(path string) string { return a.blogURL(path, false) }, "StaticURL": func(path string) string { path = filepath.Join("static", path) return a.blogURL(path, false) }, "StaticInlineCSS": func(path string) (template.CSS, error) { path = filepath.Join("static", path) b, err := staticFS.ReadFile(path) return template.CSS(b), err }, "PostURL": func(id string) string { return a.postURL(id, false) }, "AssetURL": func(id string) string { return a.assetURL(id, false) }, "DraftURL": func(id string) string { return a.draftPostURL(id, false) }, "DateTimeFormat": func(t time.Time) string { return t.Format("2006-01-02") }, } } func (a *api) parseTpl(name, tplBody string) (*template.Template, error) { tpl := template.New(name) tpl = tpl.Funcs(a.tplFuncs()) var err error if tpl, err = tpl.Parse(tplBody); err != nil { return nil, err } return tpl, nil } func (a *api) mustParseTpl(name string) *template.Template { return template.Must(a.parseTpl(name, mustReadTplFile(name))) } func (a *api) mustParseBasedTpl(name string) *template.Template { tpl := a.mustParseTpl(name) tpl = template.Must(tpl.New("base.html").Parse(mustReadTplFile("base.html"))) return tpl } type tplData struct { Payload interface{} } // executeTemplate expects to be the final action in an http.Handler func executeTemplate( rw http.ResponseWriter, r *http.Request, tpl *template.Template, payload interface{}, ) { tplData := tplData{ Payload: payload, } if err := tpl.Execute(rw, tplData); err != nil { apiutil.InternalServerError( rw, r, fmt.Errorf("rendering template: %w", err), ) return } } func (a *api) executeRedirectTpl( rw http.ResponseWriter, r *http.Request, url string, ) { executeTemplate(rw, r, a.redirectTpl, struct { URL string }{ URL: url, }) } func (a *api) renderDumbTplHandler(tplName string) http.Handler { tpl := a.mustParseBasedTpl(tplName) return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { if err := tpl.Execute(rw, nil); err != nil { apiutil.InternalServerError( rw, r, fmt.Errorf("rendering %q: %w", tplName, err), ) return } }) }