Inliner To Send Html Email

npm install @jaisocx/email-html-inliner

Status

Ready to use since the 06-th of May in the Year 2025.

The aim of the setup

The webmail apps due to security reasons do stipping out certain markup from the email messges sent with Content-Type text/html.

The package here is to solve the workaround to adjust somehow to the rules of webmail apps providers, email messages before sending they.

QA Notice

Tested with Gmail, Outlook, Protonmail, iCloud, AOL, Yahoo.

Notices

QA

My email client by my smtp relay impl could not access GMX due to some incombatibility of my smtp relay, unfortunately. I could not adjust the email message format according to exception message in the GMX response. Maybe any day later. This package was not tested with the GMX webmail app.

The issues were NOT solved: padding: <not-zero>; {max|min-}width: 100%;

The AOL and Yahoo Webmail apps strip out the CSS property box-sizing, and the default rendering rule in browsers is the box-sizing: padding-box;.

Unfortunately, I could not find the workaround, when a html node has CSS padding set, and the contents have to be set width: 100%;. In this option the look and feel is not rendered the right way. The contents are overflowing, and when designed the email message with CSS box-sizing: border-box; the Sites Dev could not know this issue, neither could notice this issue in other webmail apps.

Usage

import { EmailHtmlInliner } from "@jaisocx/email-html-inliner";

function inlineText() {
  let inliner = new EmailHtmlInliner();
  let cssHtmlPackage = inliner.cssHtmlPackage;

  // set these values before sending,
  // or omit when developing the email message.
  let baseUrlToReplace = "./../../../cdn/www/media/images/";
  let baseUrlReplacedWith = "https://my-cdn.example.com/www/media/images/";

  let inlineText = inliner.inline ( 
    document,
    "html", 
    inliner.constants.stylesPropsToCheck, 
    baseUrlToReplace, 
    baseUrlReplacedWith 
  );

  let textHtmlNode = this.htmlDocument.getElementById("inlinetext");
  textHtmlNode.innerHTML = cssHtmlPackage.escapeHTML( inlineText );
}