package middleware import ( "bytes" "fmt" "html/template" "net/http" "path" ) // SwaggerUIOpts configures the Swaggerui middlewares type SwaggerUIOpts 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 // The three components needed to embed swagger-ui SwaggerURL string SwaggerPresetURL string SwaggerStylesURL string Favicon32 string Favicon16 string // Title for the documentation site, default to: API documentation Title string } // EnsureDefaults in case some options are missing func (r *SwaggerUIOpts) EnsureDefaults() { if r.BasePath == "" { r.BasePath = "/" } if r.Path == "" { r.Path = "docs" } if r.SpecURL == "" { r.SpecURL = "/swagger.json" } if r.SwaggerURL == "" { r.SwaggerURL = swaggerLatest } if r.SwaggerPresetURL == "" { r.SwaggerPresetURL = swaggerPresetLatest } if r.SwaggerStylesURL == "" { r.SwaggerStylesURL = swaggerStylesLatest } if r.Favicon16 == "" { r.Favicon16 = swaggerFavicon16Latest } if r.Favicon32 == "" { r.Favicon32 = swaggerFavicon32Latest } if r.Title == "" { r.Title = "API documentation" } } // SwaggerUI creates a middleware to serve a documentation site for a swagger spec. // This allows for altering the spec before starting the http listener. func SwaggerUI(opts SwaggerUIOpts, next http.Handler) http.Handler { opts.EnsureDefaults() pth := path.Join(opts.BasePath, opts.Path) tmpl := template.Must(template.New("swaggerui").Parse(swaggeruiTemplate)) 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 ( swaggerLatest = "https://unpkg.com/swagger-ui-dist/swagger-ui-bundle.js" swaggerPresetLatest = "https://unpkg.com/swagger-ui-dist/swagger-ui-standalone-preset.js" swaggerStylesLatest = "https://unpkg.com/swagger-ui-dist/swagger-ui.css" swaggerFavicon32Latest = "https://unpkg.com/swagger-ui-dist/favicon-32x32.png" swaggerFavicon16Latest = "https://unpkg.com/swagger-ui-dist/favicon-16x16.png" swaggeruiTemplate = ` <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>{{ .Title }}</title> <link rel="stylesheet" type="text/css" href="{{ .SwaggerStylesURL }}" > <link rel="icon" type="image/png" href="{{ .Favicon32 }}" sizes="32x32" /> <link rel="icon" type="image/png" href="{{ .Favicon16 }}" sizes="16x16" /> <style> html { box-sizing: border-box; overflow: -moz-scrollbars-vertical; overflow-y: scroll; } *, *:before, *:after { box-sizing: inherit; } body { margin:0; background: #fafafa; } </style> </head> <body> <div id="swagger-ui"></div> <script src="{{ .SwaggerURL }}"> </script> <script src="{{ .SwaggerPresetURL }}"> </script> <script> window.onload = function() { // Begin Swagger UI call region const ui = SwaggerUIBundle({ url: '{{ .SpecURL }}', dom_id: '#swagger-ui', deepLinking: true, presets: [ SwaggerUIBundle.presets.apis, SwaggerUIStandalonePreset ], plugins: [ SwaggerUIBundle.plugins.DownloadUrl ], layout: "StandaloneLayout" }) // End Swagger UI call region window.ui = ui } </script> </body> </html> ` )