Alamofire invalid value around character 0

Question

Alamofire.request(.GET, \"url\").authenticate(user: \"\", password: \"\").responseJSON() {
    (request, response, json, error) in
    println(error)
    println(jso         


        

Answer 1

In my case , my server URL was incorrect. Check your server URL !!

Answer 2

The same issue happened to me and it actually ended up being a server issue since the content type wasn't set.

Adding

.validate(contentType: ["application/json"])

To the request chain solved it for me

Alamofire.request(.GET, "url")
        .validate(contentType: ["application/json"])
        .authenticate(user: "", password: "")
        .responseJSON() { response in
            switch response.result {
            case .Success:
                print("It worked!")
                print(response.result.value)
            case .Failure(let error):
                print(error)
            }
        }

Answer 3

In my case, there was an extra / in the URL .

Answer 4

This is how I managed to resolve the Invalid 3840 Err.

The error log

 responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed(Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around character 0." UserInfo={NSDebugDescription=Invalid value around character 0.}))

1. It was with Encoding Type used in the Request, The Encoding Type used should be acceptedin your Server-Side.

In-order to know the Encoding I had to run through all the Encoding Types:

default/ methodDependent/ queryString/ httpBody

    let headers: HTTPHeaders = [
        "Authorization": "Info XXX",
        "Accept": "application/json",
        "Content-Type" :"application/json"
    ]

    let parameters:Parameters = [
        "items": [
                "item1" : value,
                "item2": value,
                "item3" : value
        ]
    ]

    Alamofire.request("URL",method: .post, parameters: parameters,encoding:URLEncoding.queryString, headers: headers).responseJSON { response in
        debugPrint(response)
     }

2. It also depends upon the response we are recieving use the appropriate
   • responseString
   • responseJSON
   • responseData

If the response is not a JSON & just string in response use responseString

Example: in-case of login/ create token API :

"20dsoqs0287349y4ka85u6f24gmr6pah"

responseString

Answer 5

Hey guys this is what I found to be my issue: I was calling Alamofire via a function to Authenticate Users: I used the function "Login User" With the parameters that would be called from the "body"(email: String, password: String) That would be passed

my errr was exactly:

optional(alamofire.aferror.responseserializationfailed(alamofire.aferror.responseserializationfailurereason.jsonserializationfailed(error domain=nscocoaerrordomain code=3840 "invalid value around character 0." userinfo={nsdebugdescription=invalid value around character 0

character 0 is the key here: meaning the the call for the "email" was not matching the parameters: See the code below

func loginUser(email: String, password: String, completed: @escaping downloadComplete) { let lowerCasedEmail = email.lowercased()

    let header = [
        "Content-Type" : "application/json; charset=utf-8"
    ]
    let body: [String: Any] = [
        "email": lowerCasedEmail,
        "password": password
    ]

    Alamofire.request(LOGIN_USER, method: .post, parameters: body, encoding: JSONEncoding.default, headers: header).responseJSON { (response) in
        if response.result.error == nil {

            if let data = response.result.value as? Dictionary<String, AnyObject> {
                if let email = data["user"] as? String {
                    self.userEmail = email
                    print(self.userEmail)
                }
                if let token = data["token"] as? String {
                    self.token_Key = token
                    print(self.token_Key)
                }

"email" in function parameters must match the let "email" when parsing then it will work..I no longer got the error...And character 0 was the "email" in the "body" parameter for the Alamofire request:

Hope this helps