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htmlspringgrailsgrails-2.0grails-plugin

Compile CSS into HTML as Inline Style in Grails?

I want to generate GSP templates for html emails. To support more mail clients it is recommended to use inline css in html style elements.

Here is a discussion on that topic: "Compile" CSS into HTML as inline styles

Is there a Grails plugin where I can specify certain GSP files for which the CSS should be compiled as inline?

If there is no plugin, how can I specify GSP files for which the css should be complied inline?

Here is an example. I have the following GSP templates for my html mails that I send with the Grails mail plugin.

/mail/signup_mail.gsp
/mail/welcome.gsp
/mail/newsletter.gsp

Each GSP file includes a style.css file. This should be compiled inline.

Solution

  • You can fit the following Java code in your grails application.

        import java.io.IOException;
    import java.util.StringTokenizer;

    import org.jsoup.Jsoup;
    import org.jsoup.nodes.Document;
    import org.jsoup.nodes.Element;
    import org.jsoup.select.Elements;

    public class AutomaticCssInliner {

    public static void main(String[] args) throws IOException {
        final String style = "style";
        final String html = "<html>" + "<body> <style>"
                + "body{background:#FFC} \n p{background:red}"
                + "body, p{font-weight:bold} </style>"
                + "<p>...</p> </body> </html>";
        // Document doc = Jsoup.connect("http://mypage.com/inlineme.php").get();
        Document doc = Jsoup.parse(html);
        Elements els = doc.select(style);// to get all the style elements
        for (Element e : els) {
            String styleRules = e.getAllElements().get(0).data().replaceAll(
                    "\n", "").trim(), delims = "{}";
            StringTokenizer st = new StringTokenizer(styleRules, delims);
            while (st.countTokens() > 1) {
                String selector = st.nextToken(), properties = st.nextToken();
                Elements selectedElements = doc.select(selector);
                for (Element selElem : selectedElements) {
                    String oldProperties = selElem.attr(style);
                    selElem.attr(style,
                            oldProperties.length() > 0 ? concatenateProperties(
                                    oldProperties, properties) : properties);
                }
            }
            e.remove();
        }
        System.out.println(doc);// now we have the result html without the
        // styles tags, and the inline css in each
        // element
    }

private static String concatenateProperties(String oldProp, String newProp) {
    oldProp = oldProp.trim();
    if (!newProp.endsWith(";"))
       newProp += ";";
    return newProp + oldProp; // The existing (old) properties should take precedence.
}
}