Backend dude, what have you done ?

Playground.swift

/* 1 -  When your backend dev doesn't know how to REST*/

let backEndLOL: [[String: String]] = [["Key":"CAPACITY","Value":"323"],["Key":"rate","Value":"3.00"]]

// Okay let's do his/her job
extension Collection where Iterator.Element == [String: String] {
    
    var trueFuckingJson: [String: String] {
        
        let tupleArray: [(String, String)] = self.map{ dict -> [String: String] in
            guard let key = dict["Key"], let val = dict["Value"] else { return [:] }
            return [key: val]
            }.flatMap{ $0 }
 
        return Dictionary<String, String>(tupleArray, uniquingKeysWith: { (first, last) in last })
        
    }
    
}

// For backend who piss on W3C recommandation on REST Services: LOWERCASED YOUR GOD DAMN KEYS
extension Dictionary where Key == String {
    var respectW3C: Dictionary {
        var newDictionary = Dictionary()
        
        for k in keys {
            newDictionary[k.lowercased()] = self[k]
        }
        return newDictionary
    }
}


let frontEndReformat = backEndLOL.trueFuckingJson.respectW3C


/* 2 - When your backend dev DOES know how to REST and how to improve data consumption */

let trueBackEnd: [String: String] = ["capacity":"323","rate":"3.00"]

// ... and in fact that's all