Self-contained demonstration of the outstanding Goldmark markdown converter package

g.go

// Demonstrates the goldmark Markdown to HTML converter.
// Reads name of input file from command line, or creates a
// simple Markdown source file named "foo.md".
// Calls goldmark to convert it to HTML.
// Displays results to standard output.
package main

import (
	"bytes"
	"fmt"
	"github.com/yuin/goldmark"
	"io/ioutil"
	"os"
)

func main() {
	// Holds contents of the Markdown file
	var input []byte
	var err error
	filename := "foo.md"
	if len(os.Args) == 1 {
		// Create a sample Markdown source file
		// because none was specified
		err = ioutil.WriteFile(filename, []byte("hello, world."), 0644)
		if err != nil {
			panic(err.Error())
		}
	} else {
		// Use the source file specified on the command line
		filename = os.Args[1]
	}
	// Read the whole file ito memory.
	input, err = ioutil.ReadFile(filename)
	if err != nil {
		panic(err.Error())
	}

	var buf bytes.Buffer
	// Convert to Markdown

	if err := goldmark.Convert(input, &buf); err != nil {
		panic(err.Error())
	}
	// Convert the generated byte slice to string and display.
	fmt.Println(string(buf.Bytes()))
}