Switch to template, set urls as constants

linksmart · Mar 15, 2021 · c8ad11f · c8ad11f
1 parent 566753c
commit c8ad11f
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Showing 2 changed files with 35 additions and 32 deletions.
diff --git a/main.go b/main.go
@@ -30,6 +30,12 @@ const LINKSMART = `
 ╩═╝ ╩ ╝╚╝ ╩ ╩ ╚═╝ ╩ ╩ ╩ ╩ ╩╚═ ╩
 `
 
+const (
+ SwaggerUISchemeLess = "linksmart.github.io/swagger-ui/dist"
+ Spec = "https://raw.githubusercontent.com/linksmart/thing-directory/{version}/apidoc/openapi-spec.yml"
+ SourceCodeRepo = "https://github.com/linksmart/thing-directory"
+)
+
 var (
  confPath = flag.String("conf", "conf/thing-directory.json", "Configuration file path")
  schemaPath = flag.String("schema", "conf/wot_td_schema.json", "WoT Thing Description schema file path")

diff --git a/router.go b/router.go
@@ -4,10 +4,10 @@ package main
 
 import (
  "fmt"
+ "html/template"
  "io"
  "log"
  "net/http"
- "net/url"
  "strings"
 
  "github.com/gorilla/mux"
@@ -61,52 +61,49 @@ func optionsHandler(w http.ResponseWriter, _ *http.Request) {
 }
 
 func indexHandler(w http.ResponseWriter, _ *http.Request) {
- const sourceRepo = "https://github.com/linksmart/thing-directory"
- var version = "master"
+ version := "master"
  if Version != "" {
  version = Version
  }
- var spec = "https://raw.githubusercontent.com/linksmart/thing-directory/" + version + "/apidoc/openapi-spec.yml"
- var swaggerUIRelativeScheme = "//linksmart.github.io/swagger-ui/dist"
- var swaggerUISecure = "https:" + swaggerUIRelativeScheme
- // TODO: check on startup
- _, err := url.ParseRequestURI(swaggerUISecure)
- if err != nil {
- log.Printf("ERROR: Invalid SwaggerUI URL: %s", err)
- }
+ spec := strings.NewReplacer("{version}", version).Replace(Spec)
+
+ swaggerUIRelativeScheme := "//" + SwaggerUISchemeLess
+ swaggerUISecure := "https:" + swaggerUIRelativeScheme
 
  w.Header().Set("Content-Type", "text/html")
- var body string
- body += `<html>`
- body += `<h1>LinkSmart Thing Directory</h1>`
- body += fmt.Sprintf(`Version: %s</p>`, version)
- // Source code
- body += fmt.Sprintf(`<p><a href="%s">%s</a></p>`, sourceRepo, sourceRepo)
- // Registration endpoint
- body += `<p>RESTful registration endpoint: <a href="./td">/td</a></p>`
- // Swagger UI
- body += fmt.Sprintf(`<p>API Documentation: <a href="%s/?url=%s">Swagger UI</a></p>`, swaggerUISecure, spec)
- // Interactive Swagger UI
- body += fmt.Sprintf(`<p><a href="" id="swagger">Try it out!</a> (experimental; requires internet connection on both server and client sides)</p>
+
+ data := struct {
+ Version, SourceRepo, Spec, SwaggerUIRelativeScheme, SwaggerUISecure string
+ }{version, SourceCodeRepo, spec, swaggerUIRelativeScheme, swaggerUISecure}
+
+ tmpl := `
+<h1>LinkSmart Thing Directory</h1>
+<p>Version: {{.Version}}</p>
+<p><a href="{{.SourceRepo}}">{{.SourceRepo}}</a></p>
+<p>API Documentation: <a href="{{.SwaggerUISecure}}/?url={{.Spec}}">Swagger UI</a></p>
+<p><a href="" id="swagger">Try it out!</a> (experimental; requires internet connection on both server and client sides)</p>
 <script type="text/javascript">
-window.onload = function(){
- document.getElementById("swagger").href = "%s/?url=" + window.location.toString() + "openapi-spec-proxy" + window.location.pathname;
-}
-</script>`, swaggerUIRelativeScheme)
- body += `<html>`
+ window.onload = function(){
+ document.getElementById("swagger").href = "{{.SwaggerUIRelativeScheme}}/?url=" + window.location.toString() + "openapi-spec-proxy" + window.location.pathname;
+ }
+</script>`
 
- _, err = w.Write([]byte(body))
+ t, err := template.New("body").Parse(tmpl)
+ if err != nil {
+ log.Fatalf("Error parsing template: %s", err)
+ }
+ err = t.Execute(w, data)
  if err != nil {
- log.Printf("ERROR writing HTTP response: %s", err)
+ log.Fatalf("Error applying template to response: %s", err)
  }
 }
 
 func apiSpecProxy(w http.ResponseWriter, req *http.Request) {
- var version = "master"
+ version := "master"
  if Version != "" {
  version = Version
  }
- var spec = "https://raw.githubusercontent.com/linksmart/thing-directory/" + version + "/apidoc/openapi-spec.yml"
+ spec := strings.NewReplacer("{version}", version).Replace(Spec)
 
  // get the spec
  res, err := http.Get(spec)