问题
I want the users on my blogsite to be able to type in markdown text in a textarea to make a blogpost. This markdown text would then be converted with a tool like Redcarpet or kramdown. Now I also want the user to be able to call a partial view that lays out some pictures. So in other words, I want the user to be able to type in the following code anywhere in between his markdown text (and it being interpreted as erb code)
<%= render partial: "slider", locals: {imgs: ["image1.jpg", "image2.jpg"]} %>
Is this possible somehow? kramdown allows you to use block-level HTML tags (div, p, pre, …), so maybe this could be used to some advantage?
回答1:
Do you really want your customers to be able to write ERB? That's extremely dangerous, they can use any Ruby function in ERB, including Kernel functionalities. What about allowing a simple templating system, either a custom one or an existing one. For example you can use Liquid (from Shopify), provide some custom tags so they won't need all the boilerplate but just something like {% dosomething 'partial', 'img1', 'img2' %}, then you first convert liquid into normal text, then you convert markdown to html, cache it and display that to the user. An example:
# get your customer text from somewhere, like params[:markdown_text]
template = params[:markdown_text]
markdown = Liquid::Template.parse(template).render
html_text = Redcarpet::Markdown.new(renderer, extensions = {}).render(markdown)
puts html_text.to_s # => text with html tags, ensure to use `html_safe` on it in views
And you have your text ready
来源：https://stackoverflow.com/questions/31994483/rails-mix-erb-tags-with-markdown