Print NSURLRequest in cURL format (Swift 3)

URLRequest.swift

//
//  URLRequest.swift
//
//  Created by Peter Prokop on 17/08/2017.

import Foundation

public extension URLRequest {

    /// Returns a cURL command for a request
    /// - return A String object that contains cURL command or "" if an URL is not properly initalized.
    public var cURL: String {

        guard
            let url = url,
            let httpMethod = httpMethod,
            url.absoluteString.utf8.count > 0
        else {
                return ""
        }

        var curlCommand = "curl --verbose \\\n"

        // URL
        curlCommand = curlCommand.appendingFormat(" '%@' \\\n", url.absoluteString)

        // Method if different from GET
        if "GET" != httpMethod {
            curlCommand = curlCommand.appendingFormat(" -X %@ \\\n", httpMethod)
        }

        // Headers
        let allHeadersFields = allHTTPHeaderFields!
        let allHeadersKeys = Array(allHeadersFields.keys)
        let sortedHeadersKeys  = allHeadersKeys.sorted(by: <)
        for key in sortedHeadersKeys {
            curlCommand = curlCommand.appendingFormat(" -H '%@: %@' \\\n", key, self.value(forHTTPHeaderField: key)!)
        }

        // HTTP body
        if let httpBody = httpBody, httpBody.count > 0 {
            let httpBodyString = String(data: httpBody, encoding: String.Encoding.utf8)!
            let escapedHttpBody = URLRequest.escapeAllSingleQuotes(httpBodyString)
            curlCommand = curlCommand.appendingFormat(" --data '%@' \\\n", escapedHttpBody)
        }

        return curlCommand
    }

    /// Escapes all single quotes for shell from a given string.
    static func escapeAllSingleQuotes(_ value: String) -> String {
        return value.replacingOccurrences(of: "'", with: "'\\''")
    }
}

Awesome effort Peter really appreciate man.!!

Though a quick Suggestion :

.....
let allHeadersFields = allHTTPHeaderFields ?? ["":""] -- Line 33
.....
curlCommand = curlCommand.appendingFormat(" -H '%@: %@' \\\n", key, self.value(forHTTPHeaderField: key) ?? "") -- Line 37
.....

Using Null Coalescing Operator, coz force unwrap crashes sometimes. =)

I guess this will work more easily
https://gist.github.com/abhi21git/3dc611aab9e1cf5e5343ba4b58573596