Does Alamofire support JSON structured as an ordered list of values? Parameters are [String: Any], only complying to collections of name/value pairs

Question

http://json.org/ defines that JSON is built on two structures:

• A collection of name/value pairs. In various languages, this is realized as an object, record, struct, dictionary, hash table, keyed list, or associative array.
• An ordered list of values. In most languages, this is realized as an array, vector, list, or sequence.

I couldn't find a way to make Alamofire work on a post request where the parameters are [Any], which is the format required by the endpoint I'm consuming.

The error message is actualy a bit deceiving because it states "Extra argument in 'method' call" while performing a Alamofire.request but the actual problem is that parameters value is non-conforming.

Answer 1

The parameter by the name of parameters in Alamofire expects [String: Any]. If you want to send an Array through Alamofire, you can define custom ParameterEncoding like this

struct CustomEncoding: ParameterEncoding {
    var _httpBody: Data?
    func encode(_ urlRequest: Alamofire.URLRequestConvertible, with parameters: Parameters?) throws -> URLRequest {
        var request = try URLEncoding().encode(urlRequest, with: parameters)
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.httpBody = _httpBody
        return request
    }
}

Then use it like this

let body = ... // 'Array' converted to 'Data'
Alamofire.request(...,
                  method: ...,
                  parameters: [:],
                  encoding: CustomEncoding(_httpBody: body),
                  headers: ...)