I have a Firebase Cloud Function that I call from a URL rather than a function. The URL is used to load a WKWebView and the function is being called using one of the parameters in the URL, specifically the return_url.
An example of the URL to load the WKWebView would be https://domain.name?app_name=app_name&return_url=cloud_function_url.
private func loadWKWebView() {
let url = "https://domain.name"
let params = "param1=param1&return_url=\(cloud_function_url)"
var request = URLRequest(url: URL(string: url)!)
request.httpMethod = "POST"
request.httpBody = params.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { (data : Data?, response : URLResponse?, error : Error?) in
if data != nil {
if let returnString = String(data: data!, encoding: .utf8) {
DispatchQueue.main.async {
self.webView.loadHTMLString(returnString, baseURL: URL(string: url)!)
}
}
}
}
task.resume()
}
The URL loads an authentication page in which the user must enter their username and password and returns the parameter I need.
I can console log the parameter but I don’t know how to pass the data to my iOS application because it is not a function “directly” that is making the call to the function expecting the result. The result depends on whether the user enters a valid username and password.
How can I send the response once the user logs in to my app?
What you are putting in params is query parameters. That should be appended to the URL, not sent as data in a POST.
I suggest using a URLComponents struct to compose your URL from the parts you need (probably host plus queryItems.)
Related
I'm beginner in SwiftUI and I'm not familiar with variable management.
I'd like to send a very simple post request like this one with SwiftUI:
let full_path : String = "https://www.example.com/get_answer?my_message=current temperature"
I've tried with this piece of code but it didn't work.
if (URL(string: full_path) != nil) {
let url = URL(string: full_path)!
var request = URLRequest(url: url)
request.httpMethod = "POST"
var decodedAnswer = String("")
do {
let task = URLSession.shared.dataTask(with: url) { data, response, error in
print(response)
decodedAnswer = String(decoding: response, as: UTF8.self)
}
}
I have the following error:
Value of optional type 'URLResponse?' must be unwrapped to a value of
type 'URLResponse'
I don't know how to get the response.
How can I get the response from a simple Post request in SwiftUI?
Multiple issues here.
You are trying to decode the URLResponse object, but what you want is the data object in the decoder.
You seem to not know about optionals. I would refer you to the basic Apple tutorials about this topic. You can find it with your favorite search engine.
You are in an async context here. Everything inside the url datasession closure will be execute after your network request returns. The code in your function will be completed by that moment and your var decodedAnswer will be out of scope. So move it out of the function in to the class/struct.
You probably want something like this:
This should be defined in class scope or you won´t be able to use it:
var decodedAnswer: String = ""
This should be in a function:
let full_path: String = "https://www.example.com/get_answer?my_message=current temperature"
if let url = URL(string: full_path) {
var request = URLRequest(url: url)
request.httpMethod = "POST"
do {
let task = URLSession.shared.dataTask(with: url) { data, response, error in
//This converts the optionals in to non optionals that could be used further on
//Be aware this will just return when something goes wrong
guard let data = data, let response = response, error == nil else{
print("Something went wrong: error: \(error?.localizedDescription ?? "unkown error")")
return
}
print(response)
decodedAnswer = String(decoding: data, as: UTF8.self)
}
task.resume()
}
}
Sometimes I fetch information from a specific site.
But when the response is slow I would like to add a timeout function. I would like to know how.
Can I add a timeout function to the code below?
html = try String(contentsOf: url, encoding: String.Encoding.ascii)
You are not really supposed to use init(contentsOf:encoding:) to read from a remote URL. This initialiser is synchronous so while it is doing that your app's UI will freeze and the user won't be able to do anything, as you may have noticed.
You are supposed to use URLSession and URLRequest to fetch data from remote URLs. They are asynchronous so you get your data in a completion handler.
You can set a timeout in seconds when you create the URLRequest, and you will get an NSError in the completion handler if it timed out (among other reasons).
var request = URLRequest(url: URL(string: "https://example.com")!,timeoutInterval: 10)
request.addValue("text/plain", forHTTPHeaderField: "Content-Type")
request.httpMethod = "GET"
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data else {
print(String(describing: error))
return
}
let result = String(data: data, encoding: .ascii)
// do something with result
}
task.resume()
Im currently trying to work with the pho.to API in my iOS application. I am experimenting with making simple requests according to the documentation, however I cannot seem to get the request to go through successfully. Inside my API client file, I have this code:
let dataStr = """
<image_process_call>
<image_url>http://developers.pho.to/img/girl.jpg</image_url>
<methods_list>
<method order="1">
<name>desaturation</name>
</method>
<method order="2">
<name>caricature</name>
<params>type=1;crop_portrait=true</params>
</method>
</methods_list>
<thumb1_size>100</thumb1_size>
</image_process_call>
"""
let encodedStr = dataStr.replacingOccurrences(of: "\n", with: "").replacingOccurrences(of: " ", with: "")
let signData = encodedStr.hmac(key: key)
let urlStr = "https://opeapi.ws.pho.to/addtask/?app_id=\(appId)&key=\(key)&sign_data=\(signData)&data=\(encodedStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!))"
The HMAC encoding is being done according to this Stack Overflow post. Unfortunately when making a request to this URL using URLSession I get this response:
<?xml version=\"1.0\"?>\n<image_process_response><status>SecurityError</status><err_code>614</err_code><description>Error in POST parameters: one or more parameters (DATA , SIGN_DATA or APP_ID) are empty</description></image_process_response>
I feel like my issue is more related to actually forming the request rather than something specific to the API itself. I know my code is a little messy, however I was hoping that somebody could point me in the right direction in terms of making a request like this. Thanks!
As per their documentation you can see that data sent over from POST requests are in body (In cURL calls -d specifies the body of the request)
You are sending params/data in query, which the pho.to API doesn't accept, hence the error.
Here's a sample on how you can do:
let defaultSessionConfiguration = URLSessionConfiguration.default
let defaultSession = URLSession(configuration: defaultSessionConfiguration)
// Setup the request with URL
let url = URL(string: "https://opeapi.ws.pho.to/addtask")!
var urlRequest = URLRequest(url: url)
// Convert POST string parameters to data using UTF8 Encoding
let postData = yourXMLString.data(using: .utf8)
// Set the httpMethod and assign httpBody
urlRequest.httpMethod = "POST"
urlRequest.httpBody = postData
// Create dataTask
let dataTask = defaultSession.dataTask(with: urlRequest) { (data, response, error) in
// Handle your response here
}
// Fire the request
dataTask.resume()
I am trying to perform an HTTP POST request in swift that will send some data to my server using PHP file, but it crashes with the error
Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value
The token and selectedAreaNames (the error is in the first line) are just regular strings. What could be the problem?
let url = URL(string: "https://xxxxxxx.xxx/register.php/\(token)|\ (selectedAreaNames)")! //error is here...
var request = URLRequest(url: url)
request.httpMethod = "POST"
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if let error = error {
print("error: \(error)")
} else {
if let response = response as? HTTPURLResponse {
print("statusCode: \(response.statusCode)")
}
if let data = data, let dataString = String(data: data, encoding: .utf8) {
print("data: \(dataString)")
}
}
}
task.resume()
Assuming that’s really how your URL must look, you can do:
let url = URL(string: "https://xxxxxxx.xxx/register.php")!
.appendingPathComponent(token + "|" + selectedAreasNames)
That will percent escape those portions of the URL (including the |).
That having been said, this is an exceedingly unusual format for a POST request, which usually has the data being posted inside the body of the request, not just added as another path component of the URL. And if this was a GET request, where the parameters are added to the URL, you’d generally see this after a ? in the URL, separating the path of the request from the query. And this structure of simply TOKEN|VALUES is an unusual query structure, too.
My question is simple: how do you call a HTTP GET Request in Swift?
I am trying to retrieve specific data from server (I have the URL string), the problem is that the previous answers I saw, doesn't explain thoroughly how to request an HTTP Get and save the retrieved information in a variable to be used later? Thanks in advance!
Here's what I have so far:
let myURL = NSURL(string:"https://api.thingspeak.com/channels/CHANNEL_ID/last_entry
_id.txt");
let request = NSMutableURLRequest(url:myURL! as URL);
request.httpMethod = "GET"
Not sure what do following requesting the GET.
In your post you are missing the part that does the actual getting to of the data.
Your code should look something like this to get the value out of the text file.
var lastID: String?
let myURL = NSURL(string:"https://api.thingspeak.com/channels/1417/last_entry_id.txt");
let request = NSMutableURLRequest(url:myURL! as URL);
//request.httpMethod = "GET" // This line is not need
// Excute HTTP Request
let task = URLSession.shared.dataTask(with: request as URLRequest) {
data, response, error in
// Check for error
if error != nil
{
print("error=\(error)")
return
}
// Print out response string
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
print("responseString = \(responseString!)")
lastID = "\(responseString!)" // Sets some variable or text field. Not that its unwrapped because its an optional.
}
task.resume()