html-to-markdown

Convert HTML into Markdown with Go.

Installation

go get github.com/Skarlso/html-to-markdown

Usage

import "github.com/Skarlso/html-to-markdown"

converter := md.NewConverter("", true, nil)

html = `<strong>Important</strong>`

markdown, err := converter.ConvertString(html)
if err != nil {
  log.Fatal(err)
}
fmt.Println("md ->", markdown)

If you are already using goquery you can pass a selection to Convert.

markdown, err := converter.Convert(selec)

Options

The third parameter to md.NewConverter is *md.Options.

For example you can change the character that is around a bold text ("**") to a different one (for example "__") by changing the value of StrongDelimiter.

opt := &md.Options{
  StrongDelimiter: "__", // default: **
  // ...
}
converter := md.NewConverter("", true, opt)

For all the possible options look at godocs and for a example look at the example.

Adding Rules

converter.AddRules(
  md.Rule{
    Filter: []string{"del", "s", "strike"},
    Replacement: func(content string, selec *goquery.Selection, opt *md.Options) *string {
      // You need to return a pointer to a string (md.String is just a helper function).
      // If you return nil the next function for that html element 
      // will be picked. For example you could only convert an element
      // if it has a certain class name and fallback if not.
      content = strings.TrimSpace(content)
      return md.String("~" + content + "~")
    },
  },
  // more rules
)

For more information have a look at the example add_rules.

Using Plugins

If you want plugins (github flavored markdown like striketrough, tables, ...) you can pass it to Use.

import "github.com/Skarlso/html-to-markdown/plugin"
  
// Use the `GitHubFlavored` plugin from the `plugin` package.
converter.Use(plugin.GitHubFlavored())

Or if you only want to use the Strikethrough plugin. You can change the character that distinguishes the text that is crossed out by setting the first argument to a different value (for example "~~" instead of "~").

converter.Use(plugin.Strikethrough(""))

For more information have a look at the example github_flavored.

Writing Plugins

Have a look at the plugin folder for a reference implementation. The most basic one is Strikethrough.

Other Methods

Godoc

func (c *Converter) Keep(tags ...string) *Converter

Determines which elements are to be kept and rendered as HTML.

func (c *Converter) Remove(tags ...string) *Converter

Determines which elements are to be removed altogether i.e. converted to an empty string.

Related Projects

• turndown (js), a very good library written in javascript.
• lunny/html2md, which is using regex instead of goquery. I came around a few edge case when using it (leaving some html comments, ...) so I wrote my own.