How to Setup Caching on Lighttpd

Cache Configuration

server.modules += ( "mod_expire" )

$HTTP["url"] =~ "\.(jpg|jpeg|png|gif|ico|css|js)$" {
    expire.url = ( "" => "access plus 1 years" )
}

$HTTP["url"] =~ "\.(html|htm)$" {
    expire.url = ( "" => "access plus 1 hours" )
}

# Enable mod_compress
server.modules += ( "mod_compress" )
compress.cache-dir = "/var/cache/lighttpd/compress/"
compress.filetype = (
    "text/plain",
    "text/html",
    "text/css",
    "text/javascript",
    "application/javascript"
)

Key directives explained:

• mod_expire: Module for cache control
• expire.url: Sets expiration time for matched URLs
• mod_compress: Enables compression

Advanced Cache Control

server.modules += ( "mod_setenv" )

# Static assets with long cache
$HTTP["url"] =~ "\.(css|js|jpg|jpeg|png|gif)$" {
    setenv.add-response-header = (
        "Cache-Control" => "public, max-age=31536000, immutable"
    )
}

# Dynamic content with no cache
$HTTP["url"] =~ "^/(api|admin)/" {
    setenv.add-response-header = (
        "Cache-Control" => "no-store, no-cache, must-revalidate",
        "Pragma" => "no-cache"
    )
}

server.modules += ( "mod_compress" )

compress.cache-dir = "/var/cache/lighttpd/compress/"
compress.filetype = (
    "text/plain",
    "text/html",
    "text/css",
    "text/javascript",
    "application/javascript",
    "application/json",
    "application/xml",
    "image/svg+xml"
)

compress.allowed-encodings = ("gzip", "deflate")
compress.max-filesize = 1048576

Compression settings explained:

• cache-dir: Directory for compressed files
• filetype: File types to compress
• max-filesize: Maximum file size for compression

Generated Configuration

# Lighttpd configuration will appear here

Recommended Practices

• Static Assets:
  • Use long cache times (1 year) with versioned URLs
  • Add Cache-Control: public for CDN caching
  • Enable compression for text-based assets
• Dynamic Content:
  • Use shorter cache times
  • Implement cache busting for updates
  • Consider using no-cache for user-specific content
• API Responses:
  • Use no-store for sensitive data
  • Implement ETag headers for validation
  • Consider using Vary header for different responses