erlandranvinge / swift-mini-json

A single class compact simple JSON reading library in swift

swift-mini-json

A single class compact (~ 40 loc) JSON reading library in swift. Meant to be dropped in to any project without fuzz. Most recent version was tested with swift 3.2 and 4.0. If you're stuck on an older version of swift, see the "legacy" folder for deprecated versions.

Properties

JSON:

{ name: 'Ford', wheelCount: 4, weight: 2125.5, model: { name: 'F5' } }

Swift:

let car = NSData(...) // E.g. result from API, file read etc.
let json = Json(data: car)
let carName = json["name"].string()
let wheelCount = json["wheelCount"].int()
let weight = json["weight"].float()
let nestedModelName = json["model"]["name"].string()

Arrays

JSON:

{ passengers: ['Kenny', 'Benny', 'Jenny', 'Lenny'] }

Swift:

for name in json["passengers"] {
    println(name.string()) 
}

JSON:

{ 
    components: {
        wheels: [ 
            { brand: 'BrandA', radius: 55.0, boltCount: 16 }, 
            { brand: 'BrandB', radius: 56.0, boltCount: 18 } ],
        engine: /* ... */
    }
}

Swift:

for wheel in json["components"]["wheels"] {
    let brand = wheel["brand"].string()
    let radius = wheel["radius"].float()
    let boltCount = wheel["boltCount"].int()
}

Missing properties and error handling

If a property is missing, the default value is returned:

let s = json["missing-string"].string() // => ""
let i = json["missing-int"].int() // => 0
let f = json["missing-float"].float() // => 0.0
let d = json["missing-double"].double() // => 0.0

for missing in json["missing"] { } // same as iterating over empty collection

The same applies for invalid type conversions:

let s = json["string"].int() // => 0

for item in json["string"] { } // same as iterating over empty collection