MultiPartMimeHelper is a simple framework for encoding items into multipart data appropriate for putting into the HTTPBody of an NSURLRequest.

This is useful in particular for image or file upload. Most web services accept multpart encoded request bodies for file upload. This framework makes it simple to generate the mutlipart encoded data. Wrap each of the items you need to POST to the web service as a particular MultiPartPart and use those to create a MultiPartMime object.

Updated for Swift 5, updated to be pure Swift, no reliance on platform specific code.

Installing

Carthage is the recommended way to install this. Add the following to your cartfile:

github "gooddoug/MultiPartMimeHelper"

Optionally, you can copy the MultiPartMime.swift and MultiPartPart.swift files into your project and not worry about frameworks at all.

Usage examples

import MultiPartMimeHelper

func upload(img: UIImage, filename: String) {
    let multiPartMime = MultiPartMime(dict: ["name": MultiPartPart.stringWrapper(filename), "file": MultiPartPart.pngImage(img, filename)])
    var req = NSMutableURLRequest(URL: URL(string: "http://localhost:4567/upload")!)
    req.HTTPMethod = "POST"
    req.HTTPBody = multiPartMime.multiPartData
    req.setValue(multiPartMime.contentTypeString, forHTTPHeaderField:"Content-Type")
    var conn = NSURLConnection(request: req as URLRequest, delegate: self, startImmediately: true)
}

func upload(avatarPath: String, username: String, bio: String) {
    let multiPartMime = MultiPartMime(dict: ["avatar": MultiPartPart.file(path)], "username": MultiPartPart.stringWrapper(username), "bio": MultiPartPart.stringWrapper(bio)])
    var req = NSMutableURLRequest(URL: URL(string: "http://localhost:4567/upload")!)
    req.HTTPMethod = "POST"
    req.HTTPBody = multiPartMime.multiPartData
    req.setValue(multiPartMime.contentTypeString, forHTTPHeaderField:"Content-Type")
    var conn = NSURLConnection(request: req as URLRequest, delegate: self, startImmediately: true)
}

Included in the repository is a test server written with Sinatra test_app.rb To use, install the dependent gems:

gem install sinatra
gem install haml

Then run the server:

ruby test_app.rb

Contributing

Please use pull requests if you know how to fix the issue you are having. If you can't fix the issue, please file a ticket.

License

MIT License, see the 'LICENSE' file for details