Struct MimeMapper 

pub struct MimeMapper { /* private fields */ }

MIME type mapper for converting file descriptions to MIME types

Provides case-insensitive matching of file type descriptions to their corresponding MIME types.

Internally backed by a process-wide LazyLock table, so construction is effectively free and the underlying mapping is shared across all instances.

Examples

use libmagic_rs::mime::MimeMapper;

let mapper = MimeMapper::new();
assert_eq!(mapper.get_mime_type("ELF 64-bit executable"), Some("application/x-executable"));
assert_eq!(mapper.get_mime_type("PNG image data"), Some("image/png"));
assert_eq!(mapper.get_mime_type("unknown format"), None);

Implementations

impl MimeMapper

pub fn new() -> Self

Create a new MIME mapper.

This is a zero-cost constructor: all mappings are shared through a process-wide LazyLock table initialized on first use. Repeated calls to new do not rebuild the mapping.

Includes mappings for common file types:

• Executables (ELF, PE32, Mach-O)
• Archives (ZIP, GZIP, TAR, RAR, 7Z)
• Images (JPEG, PNG, GIF, BMP, WEBP, TIFF, ICO)
• Documents (PDF, PostScript)
• Audio/Video (MP3, MP4, AVI, WAV)
• Web (HTML, XML, JSON, JavaScript, CSS)
• Text formats

pub fn get_mime_type(&self, description: &str) -> Option<&'static str>

Get MIME type for a file description

Performs case-insensitive matching against known file type keywords. Returns the best matching MIME type found in the description, preferring longer (more specific) keyword matches.

Arguments

• description - The file type description to match

Returns

Some(&'static str) with the MIME type if a match is found, None otherwise.

Examples

use libmagic_rs::mime::MimeMapper;

let mapper = MimeMapper::new();

// Case-insensitive matching
assert_eq!(mapper.get_mime_type("ELF executable"), Some("application/x-executable"));
assert_eq!(mapper.get_mime_type("elf executable"), Some("application/x-executable"));

// Matches within longer descriptions
assert_eq!(mapper.get_mime_type("PNG image data, 800x600"), Some("image/png"));

pub fn len(&self) -> usize

Get the number of registered MIME mappings

pub fn is_empty(&self) -> bool

Check if the mapper has no mappings

Trait Implementations

impl Clone for MimeMapper

fn clone(&self) -> MimeMapper

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MimeMapper

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for MimeMapper

fn default() -> MimeMapper

Returns the “default value” for a type.

impl Copy for MimeMapper