Package for working with MIME type definitions and for processing streams of MIME multipart media types.
The MimeTypeResolver
class can be used to determine the MIME type of a file. It supports both using the extension of the file name and looking at magic bytes from the beginning of the file.
There is a builtin instance of MimeTypeResolver
accessible through the top level function lookupMimeType
. This builtin instance has the most common file name extensions and magic bytes registered.
import 'package:mime/mime.dart'; void main() { print(lookupMimeType('test.html')); // text/html print(lookupMimeType('test', headerBytes: [0xFF, 0xD8])); // image/jpeg print(lookupMimeType('test.html', headerBytes: [0xFF, 0xD8])); // image/jpeg }
You can build you own resolver by creating an instance of MimeTypeResolver
and adding file name extensions and magic bytes using addExtension
and addMagicNumber
.
The class MimeMultipartTransformer
is used to process a Stream
of bytes encoded using a MIME multipart media types encoding. The transformer provides a new Stream
of MimeMultipart
objects each of which have the headers and the content of each part. The content of a part is provided as a stream of bytes.
Below is an example showing how to process an HTTP request and print the length of the content of each part.
// HTTP request with content type multipart/form-data. HttpRequest request = ...; // Determine the boundary form the content type header String boundary = request.headers.contentType.parameters['boundary']; // Process the body just calculating the length of each part. request .transform(new MimeMultipartTransformer(boundary)) .map((part) => part.fold(0, (p, d) => p + d)) .listen((length) => print('Part with length $length'));