Simple Golang program for rendering a web page for my micro server: a simple landing page with useful links. This gist is in leu of a repo.

example_linkscfg.json

[
    {
        "Name": "Router Login",
        "Description": "The login page for the ADSL router",
        "URL": "http://192.168.1.1"
    }
]

landingpage.ace

= doctype html
html lang=en
  head
    title Microserver Landing Page
  = css
    html, body, div, span, p {
      margin: 0; padding: 0; border: 0; font-size: 100%; font: inherit;
    }

    #header-text {
      font-size: 60px;
      width: 100%;
      padding: 40px 0;
      margin: 0;
      -webkit-box-shadow: 0px 5px 10px 0px rgba(148,148,148,1);
      -moz-box-shadow: 0px 5px 10px 0px rgba(148,148,148,1);
      box-shadow: 0px 5px 10px 0px rgba(148,148,148,1);
      background-color: #00ff00;
      background: #f2f6f8;
      background: linear-gradient(to bottom, #f2f6f8 0%,#d8e1e7 50%,#b5c6d0 51%,#e0eff9 100%);
      text-align: center;

      color: #fff;
      font-size: 100px;
      font-weight: bold;
      font-family: Helvetica;
      text-shadow: 0 1px 0 #ccc, 0 2px 0 #c9c9c9, 0 3px 0 #bbb, 0 4px 0 #b9b9b9, 0 5px 0 #aaa, 0 6px 1px rgba(0,0,0,.1), 0 0 5px rgba(0,0,0,.1), 0 1px 3px rgba(0,0,0,.3), 0 3px 5px rgba(0,0,0,.2), 0 5px 10px rgba(0,0,0,.25), 0 10px 10px rgba(0,0,0,.2), 0 20px 20px rgba(0,0,0,.15);
    }

    #footer-text {
      font-size: 60px;
      width: 100%;
      margin: 0;
      padding: 40px 0;
      text-align: center;
    }

    #ul-heading {
      text-align: center;
      font-size: 30px;
      font-family: Helvetica;
      width: 100%;
      margin: 0;
      padding: 40px 0 0;
    }

    ul#center-list {
      text-align: center;
      font-size: 30px;
      font-family: Helvetica;
    }

    a, a:visited {
      color: #0099ff;
      font-weight: bold;
    }

    a:hover {
      color: #0033ff;
    }

    span.description-text {
      color: #888;
      font-size: 22px;
      font-style: italic;
    }

body

  h1#header-text Microserver

  {{ if .Links }}
    .link-box
      h2#ul-heading Links:
      ul#center-list
        {{range .Links }}
          li
            a href={{.URL}} {{.Name}}
            {{if .Description}}
              span.description-text.  - {{.Description}}
            {{end}}
        {{end}}
  {{end}}

  h1#footer-text ¯\_(ツ)_/¯

microserverlanding.go

package main

import (
    "encoding/json"
    "flag"
    "fmt"
    "github.com/yosssi/ace"
    "html/template"
    "io/ioutil"
    "net/http"
    "os"
    "path/filepath"
    "strconv"
)

// nested function for binding handler function parameters rather than
// relying on constants.
func buildHandler(template *template.Template, data map[string]interface{}) func(http.ResponseWriter, *http.Request) {

    // inner function to return now that we have the template and data
    // in this scope.
    return func(w http.ResponseWriter, r *http.Request) {
        // process template
        if err := template.Execute(w, data); err != nil {
            os.Stderr.WriteString(err.Error() + "\n")
            http.Error(w, "Failed to render template", http.StatusInternalServerError)
            return
        }
    }
}

type LinkCfg struct {
    Name string
    Description string
    URL string
}

func main() {

    // define flags
    portFlag := flag.Int("port", 80, "port to listen on (default 80)")
    listenFlag := flag.String("interface", "", "interface to listen on (default \"\")")

    // links configuration
    linksFileFlag := flag.String("linkscfg", "", "path to config of linked pages")

    // parse args
    flag.Parse()

    links := make([]LinkCfg, 0)
    if *linksFileFlag != "" {
        fmt.Println("linkscfg provided")

        linkscfgContent, err := ioutil.ReadFile(*linksFileFlag)
        if err != nil {
            os.Stderr.WriteString(err.Error() + "\n")
            os.Exit(1)
        }
        json.Unmarshal(linkscfgContent, &links)
    }

    // check validity of link items
    for i, l := range links {
        if l.Name == "" {
            fmt.Fprintln(os.Stderr, "Linkcfg item", i, "is missing a Name value\n")
            os.Exit(1)
        } else if l.URL == "" {
            fmt.Fprintln(os.Stderr, "Linkcfg item", i, "is missing a URL value\n")
            os.Exit(1)
        }
    }

    // construct listen string from flags
    listenDomain := "" + *listenFlag + ":" + strconv.Itoa(*portFlag)
    fmt.Println("Attempting to listen on", listenDomain, "...")

    // build data to send to template
    data := map[string]interface{}{
        "Links": links,
    }

    // load template
    thisBinary, _ := filepath.Abs(os.Args[0])
    templatePath := filepath.Join(thisBinary, "..", "landingpage")

    // attempt to load template from local file
    template, err := ace.Load(templatePath, "", nil)
    if err != nil {
        os.Stderr.WriteString(err.Error() + "\n")
        os.Exit(1)
    }

    // set up handler func
    http.HandleFunc("/", buildHandler(template, data))
    // begin serving. ListenAndServer will always return an error.
    os.Stderr.WriteString(http.ListenAndServe(listenDomain, nil).Error() + "\n")
}