Trying to setup a unit test which performs a network request and attempts to serialize the response. I'm currently getting the error: Ambiguous reference to member 'jsonObject(with:options:)'. Confused as to why this is happening as the unit test should know what JSONSerialization. is?
func testAccessKeys() {
let expected = expectation(description: "Run the Access request")
sut.request(.Access, data: nil) { finished, response in
if response != nil && finished == true {
guard let json = try? JSONSerialization.jsonObject(with: response!, options: .mutableContainers) as! [String:Any] else { return XCTFail("Access request was not a dictionary")}
XCTAssertNotNil(json?["id"])
expected.fulfill()
} else {
XCTFail("Access response was nil")
}
}
waitForExpectations(timeout: 3) { error in
if let error = error {
XCTFail("Access request failure: \(error)")
}
}
}
Make sure that response is of type Data or InputStream.
These are the only types that are accepted by this function as you can see in the documentation
Related
Trying to unit test a network call and getting the following error:
API violation - multiple calls made to -[XCTestExpectation fulfill]
If written this style of testing before, but this one seems to be creating the error and I can't seem to figure out why.
func testAccessKeys() {
let expected = expectation(description: "Run the Access request")
sut.request(.Access, data: nil) { finished, response in
if response != nil && finished == true {
if let json = response as? [String:Any] {
if json["id"] as? String != nil, json["secret"] as? String != nil {
XCTAssertNotNil(json)
expected.fulfill()
} else {
XCTFail("Access response was not in correct format")
expected.fulfill()
}
} else {
XCTFail("Access request was not a dictionary")
expected.fulfill()
}
} else {
XCTFail("Access response was nil")
expected.fulfill()
}
}
waitForExpectations(timeout: 3) { error in
if let error = error {
XCTFail("Access request failure: \(error.localizedDescription)")
}
}
}
UPDATE
Simplifying the call solved the problem:
func testAccessKeys() {
let expected = expectation(description: "Run the Access request")
sut.request(.Access, data: nil) { finished, response in
if response != nil && finished == true {
if let json = response as? [String:Any] {
if json["id"] as? String != nil, json["secret"] as? String != nil {
print("ID: \(String(describing: json["id"]))")
print("Secret: \(String(describing: json["secret"]))")
expected.fulfill()
} else {
XCTFail("Access response was not in correct format")
}
} else {
XCTFail("Access request was not a dictionary")
}
} else {
XCTFail("Access response was nil")
}
}
waitForExpectations(timeout: 3, handler: nil)
}
I had the similar problem. I resolved it by making sure that the expectation.fulfill() is called only once. Also Make sure that your expectation has different description if you have more than one expectation. Eg:self.expectation(description: "expected description")
Calling it more than once leads to crash.
In my case I had a test case dependent on another test case. There the expectation was called more than once. I resolved it by making it as single one
You could have posted your UPDATE as answer!
Im learning about Swift and i trying to make an HTTP request. My code is working but i dont know how to return the result of the request:
func makeRequest(request: URLRequest)->String{
let task = URLSession.shared.dataTask(with: request){data, response, error in
guard let data = data, error == nil else{
print("error=\(error)")
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
}
print (data)
do {
let json = try JSONSerialization.jsonObject(with: data, options: .allowFragments)
print(json)
} catch {
print("error serializing JSON: \(error)")
}
//print("responseString = \(responseString)")
}
task.resume()
return "Something"//i need to return the json as String
}
Someone can help me please? i was trying using CompletionHanlder but all the example that i found is based on swift 2, and this causes error on my code
The completion handler's type needs to be something like this:
#escaping ({argument types...})->{result type}
#escaping is needed as the completion handler is executed later when the communication is completed.
{argument types...} needs to be the types you want to pass to the handler, so in your case, a single type String. And you usually do not use the result from the handler, so you need to specify Void (aka ()).
Thus your completion handler's type needs to be:
#escaping (String)->Void
So, your method header becomes:
(You know you need a closing parenthesis for argument list.)
func makeRequest(request: URLRequest, completion: #escaping (String)->Void)
Whole your method would be something like this:
func makeRequest(request: URLRequest, completion: #escaping (String)->Void) {
let task = URLSession.shared.dataTask(with: request) {data, response, error in
guard let data = data, error == nil else{
print("error=\(error)")
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
}
print(data as NSData) //<-`as NSData` is useful for debugging
do {
let json = try JSONSerialization.jsonObject(with: data, options: .allowFragments)
print(json)
//Why don't you use decoded JSON object? (`json` may not be a `String`)
} catch {
print("error serializing JSON: \(error)")
}
//Not sure what you mean with "i need to return the json as String"
let responseString = String(data: data, encoding: .utf8) ?? ""
completion(responseString)
}
task.resume()
}
You can use it as:
makeRequest(request: request) {response in //<-`response` is inferred as `String`, with the code above.
print(response)
}
func makeRequest(request: URLRequest, completion: (result : String?)->() {
let task = URLSession.shared.dataTask(with: request){data, response, error in
guard let data = data, error == nil else{
print("error=\(error)")
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
}
print (data)
do {
let json = try JSONSerialization.jsonObject(with: data, options: .allowFragments)
print(json)
} catch {
print("error serializing JSON: \(error)")
}
completion("yourResultString")
//print("responseString = \(responseString)")
}
task.resume()
}
to call it
makeRequest(request: request) { (result : String?) in
if let result = result {
print("got result: \(result)")
}
You can't "return" the result of the request. By the time you have a result your makeRequest function has already returned to its caller. You should:
Change makeRequest to not return anything, because there's no
point
Replace the commented-out print statement with code that does
something with the responseString result.
I'm working on a app in which the api is called through NSURLSession. When the Api works correctly there is no problem but when no data is received due to any error then after Serialization it throws error but the else block for it is never called
let task = session.dataTaskWithRequest(request) { (let data, let response, let error) in
do {
guard let data:NSData = data , let response: NSURLResponse = response where error == nil else {
throw error!
}
guard let json = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? NSDictionary else{
print("Serialization failed") //This block never executes even if the Serialization Fails
throw JSONError.ConversionFailed
}
guard json.valueForKey("success") != nil else {
return
}
self.apidata = json
dispatch_async(dispatch_get_main_queue()){
self.tableView.reloadData()
}
print(json.valueForKey("success")!)
}
catch let error as JSONError{
self.showalertview(error.rawValue)
print(error.rawValue)
} catch let error as NSError{
print(error.debugDescription)
}
}
task.resume()
What I'm doing wrong here???
Consider:
do {
guard let json = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? NSDictionary else {
// A
}
} catch {
// B
}
If NSJSONSerialization throws an error (i.e. if it wasn't really a JSON response or if the response was malformed), it will proceed directly to B and the guard statement doesn't come into play. The guard statement will only execute A if and only if (a) the NSJSONSerialization call, itself, didn't throw any errors (i.e. the JSON was well-formed); but (b) the cast to the the dictionary failed (e.g. the top level JSON object was an array instead of a dictionary). That's an extremely unlikely scenario (your server would have to accidentally return a well formed JSON response that was not a dictionary, e.g. a JSON array).
To accomplish what you want, you would use try? to make sure that NSJSONSerialization wouldn't throw any errors, itself:
do {
guard let json = try? NSJSONSerialization.JSONObjectWithData(data, options: []) as? NSDictionary else {
// A
throw JSONError.ConversionFailed
}
} catch {
// B
}
By doing this, only if A performs a throw will B be called
I have this strange error when I try to parse JSON. I do an api call via an async call, to get cities slug, with a completion handler:
//Load cities slug via api call
let apiCall : webApi = webApi()
apiCall.loadCitySlugs(){(success) in
//Slug loaded in background
//Call google api to compare the slug
apiCall.compareSlugFromGoogleApi()
In the function compareSlugFromGoogleApi() there are some configuration things like the url of the async call, the post params, so nothing really relevant except the async call function:
/**
Simple async call. Returns json NSMutableArray as AnyObject
*/
func asyncCall(url : String, completed : complHandlerAsyncCall)/* -> AnyObject*/{
//Set async call params
let request = NSMutableURLRequest(URL: NSURL(string: url)!)
request.HTTPMethod = "POST"
request.HTTPBody = postParam.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request) { data, response, error in
guard error == nil && data != nil else {
// check for fundamental networking error
print("error=\(error)")
return
}
if let httpStatus = response as? NSHTTPURLResponse where httpStatus.statusCode != 200 {
// check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
}
let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)
asyncJson = responseString?.parseJSONString as! NSMutableArray
flagAsyncCall = true // true if download succeed,false otherwise
completed(success: flagAsyncCall!)
}
task.resume()
//return json! as AnyObject
}
In the async call function, I call to an extension parseJSONString that return a json object easy to parse:
extension NSString
{
var parseJSONString: AnyObject?
{
let data = self.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)
if let jsonData = data
{
// Will return an object or nil if JSON decoding fails
do
{
let message = try NSJSONSerialization.JSONObjectWithData(jsonData, options:.MutableContainers)
if let jsonResult = message as? NSMutableArray
{
return jsonResult //Will return the json array output
}
else
{
return nil
}
}
catch let error as NSError
{
print("An error occurred: \(error)")
return nil
}
}
else
{
// Lossless conversion of the string was not possible
return nil
}
}
}
And here is where I'm having a problem with the Google call. Everything looks more or less ok, but it returns a nil value from the extension and then, back in the async call, it throws me this error:
still the response object is not empty:
It throws an error because parseJSONString returns nil, and when you unwrap that ! it crashes. You should check if parseJSONString returns non nil. if let parsed = parseJSONString { do something }
Use NSDictionary instead of NSMutableArray.
I'm currently developing my first iOS app using Swift 2.0 and Xcode Beta 2. It reads an external JSON and generates a list in a table view with the data. However, I'm getting a strange little error that I can't seem to fix:
Extra argument 'error' in call
Here is a snippet of my code:
let task = session.dataTaskWithURL(url!, completionHandler: {data, response, error -> Void in
print("Task completed")
if(error != nil){
print(error!.localizedDescription)
}
var err: NSError?
if let jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary{
if(err != nil){
print("JSON Error \(err!.localizedDescription)")
}
if let results: NSArray = jsonResult["results"] as? NSArray{
dispatch_async(dispatch_get_main_queue(), {
self.tableData = results
self.appsTableView!.reloadData()
})
}
}
})
The error is thrown at this line:
if let jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary{
Can someone please tell me what I'm doing wrong here?
With Swift 2, the signature for NSJSONSerialization has changed, to conform to the new error handling system.
Here's an example of how to use it:
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? NSDictionary {
print(jsonResult)
}
} catch let error as NSError {
print(error.localizedDescription)
}
With Swift 3, the name of NSJSONSerialization and its methods have changed, according to the Swift API Design Guidelines.
Here's the same example:
do {
if let jsonResult = try JSONSerialization.jsonObject(with: data, options: []) as? [String:AnyObject] {
print(jsonResult)
}
} catch let error as NSError {
print(error.localizedDescription)
}
Things have changed in Swift 2, methods that accepted an error parameter were transformed into methods that throw that error instead of returning it via an inout parameter. By looking at the Apple documentation:
HANDLING ERRORS IN SWIFT:
In Swift, this method returns a nonoptional result and is marked with the throws keyword to indicate that it throws an error in cases of failure.
You call this method in a try expression and handle any errors in the catch clauses of a do statement, as described in Error Handling in The Swift Programming Language (Swift 2.1) and Error Handling in Using Swift with Cocoa and Objective-C (Swift 2.1).
The shortest solution would be to use try? which returns nil if an error occurs:
let message = try? NSJSONSerialization.JSONObjectWithData(receivedData, options:.AllowFragments)
if let dict = message as? NSDictionary {
// ... process the data
}
If you're also interested into the error, you can use a do/catch:
do {
let message = try NSJSONSerialization.JSONObjectWithData(receivedData, options:.AllowFragments)
if let dict = message as? NSDictionary {
// ... process the data
}
} catch let error as NSError {
print("An error occurred: \(error)")
}
This has been changed in Swift 3.0.
do{
if let responseObj = try JSONSerialization.jsonObject(with: results, options: .allowFragments) as? NSDictionary{
if JSONSerialization.isValidJSONObject(responseObj){
//Do your stuff here
}
else{
//Handle error
}
}
else{
//Do your stuff here
}
}
catch let error as NSError {
print("An error occurred: \(error)") }