UserAgent is optional in defaultHTTPHeaders

[shlowdy]

Hello
In Manager.defaultHTTPHeaders print out the userAgent

    // User-Agent Header; see https://tools.ietf.org/html/rfc7231#section-5.5.3
    let userAgent: String = {
        if let info = NSBundle.mainBundle().infoDictionary {
            let executable = info[kCFBundleExecutableKey as String] ?? "Unknown"
            let bundle = info[kCFBundleIdentifierKey as String] ?? "Unknown"
            let version = info[kCFBundleVersionKey as String] ?? "Unknown"
            let os = NSProcessInfo.processInfo().operatingSystemVersionString ?? "Unknown"
            var mutableUserAgent = NSMutableString(string: "\(executable)/\(bundle) (\(version); OS \(os))") as CFMutableString
            let transform = NSString(string: "Any-Latin; Latin-ASCII; [:^ASCII:] Remove") as CFString
            if CFStringTransform(mutableUserAgent, UnsafeMutablePointer<CFRange>(nil), transform, false) {
                return mutableUserAgent as String
            }
        }
        return "Alamofire"
    }()
    print("useragent__\(userAgent)")
    return ["Accept-Encoding": acceptEncoding, "Accept-Language": acceptLanguage, "User-Agent": userAgent]

the output
useragent__Optional(Hello)/Optional(com.test.Hello) (Optional(1); OS Version 9.2 (Build 13C75))

It turns out that the executable, bundle, version is Optional
info[kCFBundleExecutableKey as String] as? String ?? "Unknown"
will be ok

xcode 7.2.1 iOS 9.2.1

ignore me if you already know that^^

[cnoon]

Hmmmm...doesn't seem possible @shlowdy. The type on userAgent is String, not String?. Also, I haven't seen the optional arguments in the User-Agent header before.

[shlowdy]

Sorry about the title.
The userAgent is String indeed.
What I mean is these three
let executable = info[kCFBundleExecutableKey as String] ?? "Unknown"
let bundle = info[kCFBundleIdentifierKey as String] ?? "Unknown"
let version = info[kCFBundleVersionKey as String] ?? "Unknown"
they are optional
If you do this
let executable: String = info[kCFBundleExecutableKey as String] ?? "Unknown"
you will get a error

[cnoon]

Ah...thanks for clarifying @shlowdy. I definitely see what you mean. The logic works fine as is, since it's using either the AnyObject coming from the dictionary or defaulting to a String which is then stored as a String. Then, when substituting into the new mutable string, each AnyObject's `description is used to build the final String. All this logic works correctly, but can be a bit misleading.

In order to simplify, I just pushed 3052587 to make things a bit easier to digest. Hopefully that helps clarify things.

Cheers. 🍻