package middleware import ( "bytes" "fmt" "html/template" "net/http" "path" ) // RedocOpts configures the Redoc middlewares type RedocOpts struct { // BasePath for the UI path, defaults to: / BasePath string // Path combines with BasePath for the full UI path, defaults to: docs Path string // SpecURL the url to find the spec for SpecURL string // RedocURL for the js that generates the redoc site, defaults to: https://cdn.jsdelivr.net/npm/redoc/bundles/redoc.standalone.js RedocURL string // Title for the documentation site, default to: API documentation Title string } // EnsureDefaults in case some options are missing func (r *RedocOpts) EnsureDefaults() { if r.BasePath == "" { r.BasePath = "/" } if r.Path == "" { r.Path = "docs" } if r.SpecURL == "" { r.SpecURL = "/swagger.json" } if r.RedocURL == "" { r.RedocURL = redocLatest } if r.Title == "" { r.Title = "API documentation" } } // Redoc creates a middleware to serve a documentation site for a swagger spec. // This allows for altering the spec before starting the http listener. // func Redoc(opts RedocOpts, next http.Handler) http.Handler { opts.EnsureDefaults() pth := path.Join(opts.BasePath, opts.Path) tmpl := template.Must(template.New("redoc").Parse(redocTemplate)) buf := bytes.NewBuffer(nil) _ = tmpl.Execute(buf, opts) b := buf.Bytes() return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) { if r.URL.Path == pth { rw.Header().Set("Content-Type", "text/html; charset=utf-8") rw.WriteHeader(http.StatusOK) _, _ = rw.Write(b) return } if next == nil { rw.Header().Set("Content-Type", "text/plain") rw.WriteHeader(http.StatusNotFound) _, _ = rw.Write([]byte(fmt.Sprintf("%q not found", pth))) return } next.ServeHTTP(rw, r) }) } const ( redocLatest = "https://cdn.jsdelivr.net/npm/redoc/bundles/redoc.standalone.js" redocTemplate = `