How do I inline CSS in Go for email templates using douceur?

Use the inliner package by calling inliner.Inline() on your HTML string after installing the library with 'go get'. The README provides a code example that shows inlining styles for elements like paragraphs, making it straightforward for email generation.

Douceur vs premailer for HTML email inlining?

Douceur is a Go library focused on simplicity and internal style tags, while premailer is a Ruby gem that handles external stylesheets and offers more email optimization features. Choose douceur for Go projects needing lightweight inlining, and premailer for Ruby environments with complex style dependencies.

Does douceur support CSS media queries?

No, douceur's inliner is designed for element-specific styles and may not handle media queries effectively. The parser is inspired by CSS3 but lacks full support for advanced features like responsive design rules.

Can douceur parse CSS from a URL or external file?

No, it only processes CSS provided as a string or from local files; you must manually fetch external stylesheets first. The README confirms it does not fetch external resources, limiting its use for web pages with linked CSS.

How to install and use the douceur CLI tool?

Install it with 'go install github.com/aymerick/douceur', then run commands like 'douceur parse input.css' to parse CSS or 'douceur inline input.html' to inline styles. The README includes examples for both parsing and inlining from the terminal.

What are the main limitations of douceur's inliner?

It only inlines styles from internal style tags, ignores external stylesheets, and may not support all CSS properties or complex selectors. Additionally, it focuses on adding inline attributes for compatibility rather than full CSS transformation.

Open-Awesome

douceur

MITGov0.2.0

A simple CSS parser and inliner library written in Go for processing and embedding styles in HTML.

GitHub

262 stars46 forks0 contributors

What is douceur?

Douceur is a Go library and command-line tool for parsing CSS and inlining styles into HTML documents. It solves the problem of embedding CSS directly within HTML, which is essential for scenarios like email template generation where external stylesheets are not supported. The library parses CSS into a structured format and applies styles as inline attributes, enhancing compatibility.

Target Audience

Go developers working on email template systems, document processors, or any application requiring CSS manipulation and HTML style embedding. It's also suitable for those needing a lightweight CSS parsing tool in Go.

Value Proposition

Developers choose Douceur for its simplicity, reliability, and focused feature set—it does one thing well without bloat. Its integration with Go's ecosystem and ability to handle real-world CSS quirks make it a practical alternative to more complex solutions.

Overview

A simple CSS parser and inliner in Go

Use Cases

Best For

Generating HTML email templates with inline styles
Parsing and cleaning CSS in Go applications
Converting CSS styles to inline HTML attributes for compatibility
Building tools that process or transform HTML documents
Embedding CSS from style tags into HTML elements programmatically
Command-line CSS file parsing and inspection

Not Ideal For

Applications requiring real-time CSS processing in web browsers
Projects that depend heavily on external stylesheets from URLs or CDNs
Teams needing advanced CSS features like SASS compilation or vendor prefixing
Environments where a full-featured, multi-language CSS framework is preferred

Pros & Cons

Pros

Simple and Reliable API

Focuses on straightforward CSS parsing and inlining without bloat, as emphasized in the README's philosophy, making it easy to integrate into Go projects.

Graceful Error Handling

Parser handles comments and malformed CSS gracefully, ensuring robust processing of real-world inputs, demonstrated in the code example with messy CSS.

Enhanced Email Compatibility

Inliner adds equivalent HTML attributes like bgcolor for background-color, improving support for older email clients, as shown in the README example.

Included CLI Tool

Provides a command-line interface for parsing CSS files and inlining HTML documents directly, with simple commands like 'douceur inline input.html'.

Cons

No External Stylesheet Support

Explicitly stated in the README that it does not fetch external stylesheets, limiting use for documents with linked CSS or remote resources.

Dependency on Third-Party Libraries

Relies on Gorilla CSS3 tokenizer and goquery, which can introduce versioning conflicts or increase project dependency complexity.

Limited CSS3 Compliance

Inspired by CSS3 syntax but not fully compliant, potentially missing support for newer CSS features or complex selectors like media queries.

Frequently Asked Questions

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