blogtheme

Blogtheme Package

The blogtheme package provides a lightweight theme system specifically designed for blog content rendering. It converts JSON-structured block content into HTML with blog-appropriate styling.

Features

• JSON-based Input: Accepts blocks as JSON strings for easy storage and transport
• Blog-focused Styling: Pre-configured CSS styles optimized for blog content
• Lightweight: Minimal block types focused on common blog content needs
• Error Handling: Graceful handling of unsupported block types
• Extensible: Easy to add new block renderers

Usage

Basic Theme Usage

import (
    "github.com/dracory/base/blogtheme"
    "github.com/dracory/ui"
)

// Create blocks
blocks := []ui.BlockInterface{
    func() ui.BlockInterface {
        block := ui.NewBlock()
        block.SetType("paragraph")
        block.SetParameter("content", "Welcome to my blog!")
        return block
    }(),
    func() ui.BlockInterface {
        block := ui.NewBlock()
        block.SetType("heading")
        block.SetParameter("level", "1")
        block.SetParameter("content", "My First Post")
        return block
    }(),
}

// Convert to JSON
blocksJSON, err := ui.MarshalBlocksToJson(blocks)
if err != nil {
    log.Fatal(err)
}

// Create theme and render HTML
theme, err := blogtheme.New(blocksJSON)
if err != nil {
    log.Fatal(err)
}

html := theme.ToHtml()
style := theme.Style()

fmt.Println(html)
// Output: <p>Welcome to my blog!</p><h1 style="margin-bottom:20px;margin-top:20px;">My First Post</h1>

Integration with Blog Systems

// Example: Rendering blog post content
func renderBlogPost(contentJSON string) (string, string, error) {
    theme, err := blogtheme.New(contentJSON)
    if err != nil {
        return "", "", err
    }
    
    html := theme.ToHtml()
    style := theme.Style()
    
    return html, style, nil
}

Supported Block Types

The blogtheme supports a focused set of block types commonly needed for blog content:

Text Content

• paragraph: Standard text paragraphs
• heading: H1-H6 headings with configurable levels
• text: Inline text spans

Media

• image: Images with URL support
• hyperlink: Links with URL and text content

Lists

• unordered_list: Bulleted lists (UL elements)
• ordered_list: Numbered lists (OL elements)
• list_item: List items (LI elements)

Special

• raw: Raw HTML content for custom markup

Block Parameters

Common Parameters

• content: The main content/text of the block

Heading-specific

• level: Heading level (1-6)

Image-specific

• image_url: URL of the image

Hyperlink-specific

• url: Link URL
• content: Link text/HTML

Styling

The blogtheme provides built-in CSS styling optimized for blog content:

.BlogTitle {
    font-family: Roboto, sans-serif;
}
.BlogContent {
    font-family: Roboto, sans-serif;
}
h1 { 
    margin-bottom: 20px;
    font-size: 48px;
}
h2 { 
    margin-bottom: 20px;
    font-size: 36px;
}
h3 {
    margin-bottom: 20px;
    font-size: 24px;
}
h4 {
    margin-bottom: 20px;
    font-size: 18px;
}
h5 {
    margin-bottom: 20px;
    font-size: 16px;
}
h6 {
    margin-bottom: 20px;
    font-size: 14px;
}

JSON Input Format

The theme expects blocks in JSON format. Here's an example:

[
  {
    "id": "block-1",
    "type": "heading",
    "sequence": 1,
    "parentId": "",
    "content": "Blog Post Title",
    "attributes": {
      "level": "1"
    }
  },
  {
    "id": "block-2", 
    "type": "paragraph",
    "sequence": 2,
    "parentId": "",
    "content": "This is the blog post content.",
    "attributes": {}
  }
]

Error Handling

Invalid JSON

theme, err := blogtheme.New("{ invalid json }")
if err != nil {
    // Handle JSON parsing error
    return "", err
}

Unsupported Block Types

Unsupported block types are rendered with warning messages:

<div class="alert alert-warning">
  Block custom_type renderer does not exist
</div>

Comparison with Webtheme

The blogtheme is a simplified version of webtheme focused on blog content:

Dependencies

• github.com/dracory/ui: Block interface and JSON utilities
• github.com/dracory/hb: HTML building library
• github.com/dracory/blockeditor: Block tree utilities
• github.com/samber/lo: Functional utilities
• github.com/spf13/cast: Type casting utilities

License

This package is part of the Dracory base package and follows the same licensing terms.