(Swift 3,4,5...) Firebase PATCH - Updating Data

Uses the PATCH method to update record with new information. The data used in this example is at Chilkat Firebase Pigs Database, and is shown here:

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func chilkatTest() {
    // Uses the PATCH method to update a Firebase record.

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // This example assumes a JWT authentication token, if required, has been previously obtained.
    // See Get Firebase Access Token from JSON Service Account Private Key for sample code.

    // Load the previously obtained Firebase access token into a string.
    let fac = CkoFileAccess()!
    var accessToken: String? = fac.readEntireTextFile("qa_data/tokens/firebaseToken.txt", charset: "utf-8")
    if fac.lastMethodSuccess != true {
        print("\(fac.lastErrorText!)")
        return
    }

    let rest = CkoRest()!

    // Make the initial connection (without sending a request yet).
    // Once connected, any number of requests may be sent.  It is not necessary to explicitly
    // call Connect before each request.  
    var success: Bool = rest.connect("chilkat.firebaseio.com", port: 443, tls: true, autoReconnect: true)
    if success != true {
        print("\(rest.lastErrorText!)")
        return
    }

    let authGoogle = CkoAuthGoogle()!
    authGoogle.accessToken = accessToken
    rest.setAuthGoogle(authGoogle)

    // Chilkat's sample data (pig-rescue data) is publicly readable at: https://chilkat.firebaseio.com/.json
    // This data is publicly readable, but not writable.  You'll need to 
    // run against your own database..

    // We're going to update "Molly II" to "Molly III"
    let pigNameUpdate = CkoJsonObject()!
    pigNameUpdate.append("name", value: "Molly III")

    // The string content of the last arg passed is  {"name":"Molly III"} 
    var jsonResponse: String? = rest.fullRequest("PATCH", uriPath: "/pig-rescue/animal/-KI3bD-FU_Dake7sYOiP.json", bodyText: pigNameUpdate.emit())
    if rest.lastMethodSuccess != true {
        // Something happened in the communications (either no request was sent, or no response was received.
        // (The Chilkat REST API also has lower-level methods where an app can send the request in one call,
        // and then receive the response in another call.)
        print("\(rest.lastErrorText!)")
        return
    }

    // Check the response status code.   A 200 response status indicates success.
    if rest.responseStatusCode.intValue != 200 {
        print("\(rest.responseStatusText!)")
        print("\(jsonResponse!)")
        print("Failed.")
        return
    }

    // When successful, the response contains the data written.
    print("\(jsonResponse!)")
    print("Success.")

}