feat(utils): add text email generation utility methods

[niloysikdar]

Requirements:

• generateTextEmailFromHTML function which will take the HTML string and convert it to plaintext version
• generateTextEmail function which will accept the JSX Layout and convert that into plaintext format using generateEmail and generateTextEmailFromHTML functions

The Pull Request covers:

• generateTextEmailFromHTML utility function
• generateTextEmail function
• Tests for generateTextEmailFromHTML and generateTextEmail methods

Limitations:

• Preheader text will also get included in the text version, which shouldn't be the case

Some proposed solutions:

• We tried using some HOC and complex logic strategy with some props (mode = "text") to handle the functionality of not rendering the text from the Preheader, but it was throwing issues for some cases and moreover, it was only increasing the complexity in case of implementation.

• We can remove the Preheader manually from our DOM and then generate the text version, and this won't add the preheader text to the final generated text.

  import { DOMParser, XMLSerializer } from "xmldom";
  
  const domparser = new DOMParser();
  const xmlSerializer = new XMLSerializer();
  
  const res = domparser.parseFromString(html, "text/html");
  const pre = res.getElementById("preheader");
  res.removeChild(pre);
  const finalHTML = xmlSerializer.serializeToString(res);
  

• I've found another library html-to-text that can help us to achieve this goal. We can use the selectors option to pass our custom selector for the Preheader component and then exclude it from the final generated text.

  const text = convert(html, {
    selectors: [{ selector: '.preheader', format: 'skip' }],
  });
  

  But the only problem with this library is that we also need to define our custom selectors and formatters for all h tags to hashify them in the generated text output.

Resolves #60

Signed-off-by: Niloy Sikdar niloysikdar30@gmail.com

[agentmilindu]

I think you need to have tests for all types of components we have to make sure all the components turn to the correct text version of them.

[niloysikdar]

I think you need to have tests for all types of components we have to make sure all the components turn to the correct text version of them.

Yeah, make sense, doing the changes.

[github-actions]

🎉 This PR is included in version 1.7.0 🎉