🏞 Multipart parser and serializer with Codable
support for Multipart Form Data.
The table below shows a list of MultipartKit major releases alongside their compatible NIO and Swift versions.
Version | NIO | Swift | SPM |
---|---|---|---|
4.0 | 2.2 | 5.4+ | from: "4.0.0" |
3.0 | 1.0 | 4.0+ | from: "3.0.0" |
2.0 | N/A | 3.1+ | from: "2.0.0" |
1.0 | N/A | 3.1+ | from: "1.0.0" |
Use the SPM string to easily include the dependency in your Package.swift
file.
.package(url: "https://github.com/vapor/multipart-kit.git", from: ...)
MultipartKit supports the following platforms:
MultipartKit is a multipart parsing and serializing library. It provides Codable
support for the special case of the multipart/form-data
media type through a FormDataEncoder
and FormDataDecoder
. The parser delivers its output as it is parsed through callbacks suitable for streaming.
Let's define a Codable
type and a choose a boundary used to separate the multipart parts.
struct User: Codable {
let name: String
let email: String
}
let user = User(name: "Ed", email: "[email protected]")
let boundary = "abc123"
We can encode this instance of a our type using a FormDataEncoder
.
let encoded = try FormDataEncoder().encode(foo, boundary: boundary)
The output looks then looks like this.
--abc123
Content-Disposition: form-data; name="name"
Ed
--abc123
Content-Disposition: form-data; name="email"
[email protected]
--abc123--
In order to decode this message we feed this output and the same boundary to a FormDataDecoder
and we get back an identical instance to the one we started with.
let decoded = try FormDataDecoder().decode(User.self, from: encoded, boundary: boundary)
null
As there is no standard defined for how to represent null
in Multipart (unlike, for instance, JSON), FormDataEncoder and FormDataDecoder do not support encoding or decoding null
respectively.
Nested structures can be represented by naming the parts such that they describe a path using square brackets to denote contained properties or elements in a collection. The following example shows what that looks like in practice.
struct Nested: Encodable {
let tag: String
let flag: Bool
let nested: [Nested]
}
let boundary = "abc123"
let nested = Nested(tag: "a", flag: true, nested: [Nested(tag: "b", flag: false, nested: [])])
let encoded = try FormDataEncoder().encode(nested, boundary: boundary)
This results in the content below.
--abc123
Content-Disposition: form-data; name="tag"
a
--abc123
Content-Disposition: form-data; name="flag"
true
--abc123
Content-Disposition: form-data; name="nested[0][tag]"
b
--abc123
Content-Disposition: form-data; name="nested[0][flag]"
false
--abc123--
Note that the array elements always include the index (as opposed to just []
) in order to support complex nesting.
link |
Stars: 124 |
Last commit: 4 weeks ago |
Fixes an issue where the Decodable
object is expecting a single part, but receives a set of keys causing the FormDataDecoder
to get stuck in an infinite loop and eventually crash. This changes the behaviour to throw an error in this case
Swiftpack is being maintained by Petr Pavlik | @ptrpavlik | @swiftpackco | API | Analytics