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returning the value of REST Api response to the calling function

I request your help in solving this pesky problem. I am trying to return the value of 'response' returned by the REST API call, to the calling program. I get null string. Here is the code for your reference. In this code, I want the value of the variable 'response' returned to the caller in onCreate, ie 'restApiResponse' variable.
Thank you very much.
-Vittal
PS: I am a newbie to Kotlin/Android programming.
class OpeningActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_opening)
var restApiResponse = getAPIResponse() // <<<< restApiResponse is empty string
val submitButton = findViewById<Button>(R.id.submitBtn)
submitButton.setOnClickListener() {
val intent = Intent(this, MainActivity::class.java)
startActivity(intent)
}
}
fun getAPIResponse() : String {
val myUrl = "YOUR REST API CALL URL"
var jsonObject = JSONObject();
val queue = Volley.newRequestQueue(this);
cpyResponse = StringBuilder();
val stringRequest = object: StringRequest(Request.Method.GET, myUrl,
Response.Listener<String> { response ->
Log.d("A", "VK: Response is: " + response.substring(0, 500))
cpyResponse.append(response.toString())
// .. cpyResponse now has the content of response.
},
Response.ErrorListener { })
{
override fun getHeaders(): MutableMap<String, String> {
val headers = HashMap<String, String>()
headers.put("X-API-KEY", "r0IS395C2D8ITjSKV05F610yPXsDQZjllmprr");
return headers
}
}
queue.add(stringRequest)
Log.d("A", "VK: Response is: " + response) // <<<<-- value of response is gone.. it is an empty string!!!!!! :(
return cpyResponse.toString() // <<< --- cpyResource is also empty string
}

Android: HTTP request with Volley fails to call with parameters

I deployed a NLP model as an API with Flask. Now I want to call the API from my simple Android app to process some text and to return a prediction, however when the Android App performs the HTTP request using Volley it does not add the parameters in the URL for some reason. Here is the code:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// button
val showButton = findViewById<Button>(R.id.showInput)
// text
val editText = findViewById<EditText>(R.id.editText)
// Setting On Click Listener
showButton.setOnClickListener {
// user input
val text = editText.text
// Instantiate the RequestQueue.
val queue = Volley.newRequestQueue(this)
val url = "http://192.168.100.12:5000/"
// Request a string response from the provided URL.
val request = object : StringRequest(Request.Method.POST,
url,
Response.Listener {
response ->
editText.setText(response.toString())
},
Response.ErrorListener { error ->
Log.i("error ", error.toString())
editText.setText("Volley error: $it ")
}) {
override fun getBodyContentType(): String {
return "application/json"
}
#Throws(AuthFailureError::class)
override fun getBody(): ByteArray {
val params = HashMap<String,String>()
params.put("text", text.toString())
return params.toString().toByteArray()
}
}
// Add the request to the RequestQueue.
queue.add(request)
// Showing the response
Toast.makeText(this, text, Toast.LENGTH_SHORT).show()
}
}
}
In essence, I am expecting the URL to be "http://192.168.100.12:5000/?text=<insert_text_here>", but the actual URL that the app calls is just "http://192.168.100.12:5000" without the parameters.
I know this because my Flask app returns this error:
AttributeError: 'NoneType' object has no attribute 'lower'
The error response code is 500.
I tested the Flask API with both the browser and Postman and it is working fine, but just in case I will leave the code here:
from flask import Flask,render_template,url_for,request,jsonify
from sklearn.externals import joblib
import traceback
app = Flask(__name__)
#app.route("/",methods=['GET','POST'])
def predict():
try:
tweet = request.args.get('text')
model = open('model.pkl','rb')
model = joblib.load(model)
prediction = model.predict([tweet])
if prediction == [0]:
return 'This tweet does not violate our Community Guidelines'
else:
return 'This tweet violates out Community Guidelines for hate speech'
except:
return traceback.format_exc()
if __name__ == '__main__':
app.run(host = '192.168.100.12',debug=True)
So far I also have tried the code from this post as well as using the GET method with getParams() function instead of getBody() as shown below, but none of them worked.
#Throws(AuthFailureError::class)
override fun getParams(): Map<String, String>? {
val params: HashMap<String, String> = HashMap()
params["text"] = text.toString()
return params
}
Can you please help me solve this issue? I would be very grateful.

I need help for post to my api. What should I do?

I'm creating a login for my application.
I am currently stuck in posting problems to my API
This is my API that which is made to support login.
{
success: false,
message: "Please provide complete and accurate information.",
data: [ ]
}
fun loginUrlSuccess(urlApi : String) {
Log.d("login", urlApi)
authSignin_cgi = gson.fromJson(urlApi, DtoProfile::class.java)
loginsSuccess = authSignin_cgi.success
val queue = Volley.newRequestQueue(context)
val stringReq = object : StringRequest(Request.Method.POST,urlApi,Response.Listener<String>{ response ->
Log.w("response",response)
Toast.makeText(context,"Loging success..",Toast.LENGTH_SHORT).show()
if (loginsSuccess){
Toast.makeText(context,authSignin_cgi.message,Toast.LENGTH_LONG).show()
} else {
Toast.makeText(context,authSignin_cgi.message,Toast.LENGTH_LONG).show()
}
},Response.ErrorListener { error ->
Log.w("error", error.toString())
Toast.makeText(context, "error..$error",Toast.LENGTH_SHORT).show()
}){
override fun getParams(): MutableMap<String, String> {
val param = HashMap<String, String>()
val userEmail = textEmail.text.toString().trim()
val userPassword = textPassword.text.toString().trim()
param["useremail"] = userEmail
param["userpassword"] = userPassword
return param
}
}
queue.add(stringReq)
}
I get an error from the Logcat screen.
So what do I have to do?
04-04 15:31:43.614 8365-8699/com.example.atimeonlin5 E/Volley: [700] NetworkDispatcher.processRequest: Unhandled exception java.lang.RuntimeException: Bad URL {"success":false,"message":"โปรดระบุข้อมูลให้ถูกต้องครบถ้วน","data":[]}
java.lang.RuntimeException: Bad URL {"success":false,"message":"โปรดระบุข้อมูลให้ถูกต้องครบถ้วน","data":[]}

All right , you should try to construct an Url object instead of type String !

You should use an url (like "http://www.google.com"), not a random string. Your urlApi is not url.
Example from doc:
val textView = findViewById<TextView>(R.id.text)
// ...
// Instantiate the RequestQueue.
val queue = Volley.newRequestQueue(this)
val url = "http://www.google.com"
// Request a string response from the provided URL.
val stringRequest = StringRequest(Request.Method.GET, url,
Response.Listener<String> { response ->
// Display the first 500 characters of the response string.
textView.text = "Response is: ${response.substring(0, 500)}"
},
Response.ErrorListener { textView.text = "That didn't work!" })
// Add the request to the RequestQueue.
queue.add(stringRequest)

Request working on Insomnia but not Android?

I have the following request on Insomnia:
Which is working fine!
But, if I try to do this on Android with volley I get a "ServerError":
fun createRequest() {
val params = JSONObject()
params.put("device_key", Settings.Secure.getString(contentResolver, Settings.Secure.ANDROID_ID))
params.put("edition_date", "2018-02-12 00:00:00")
params.put("publication", 1)
val headers = hashMapOf<String, String>()
headers["Authorization"] = "My Token"
headers["Content-Type"] = "application/x-www-form-urlencoded"
getPDF(this, params, headers)
}
fun getPDF(activity: Activity, params: JSONObject, headers: HashMap<String, String>) {
val request = object : JsonObjectRequest(Request.Method.POST, "My URL", params,
Response.Listener {
print("asd")
},
Response.ErrorListener {
it.printStackTrace()
}
) {
override fun getHeaders(): Map<String, String> { return headers } }
request.retryPolicy = DefaultRetryPolicy(0, DEFAULT_MAX_RETRIES, DEFAULT_BACKOFF_MULT)
Volley.newRequestQueue(activity).add(request)
}
I'm only getting a "ServerError" with a code 500.
What could I be doing wrong in Android? Am I not settings the header correctly? Or could be the params?

In Insomnia you are making a request and the body is a form, while in Android you are trying to send a JSON. Make sure your body consists of key-value pairs and not a JSON object.

How to pass JWT token from one activity to another?

I have the following onCreate class in MainActivity and proven to be able to work with my server. It is able to extract out the JWT token
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setSupportActionBar(toolbar)
submitButton = findViewById<Button>(R.id.btn_submit)
// Volley code is here
val url = "http://192.168.1.8:4000"
submitButton.setOnClickListener({
val pinCode = pin_code.text.toString()
queue = Volley.newRequestQueue(this)
val params = HashMap<String, String>()
params.put("pin_code", pinCode)
val request = object : JsonObjectRequest(Request.Method.POST, url + "/api/employees/token", JSONObject(params),
Response.Listener<JSONObject> { response ->
val token = response
.getJSONObject("data")
.getString("token")
val myIntent = Intent(this, SiteActivity::class.java)
startActivityForResult(myIntent, 0)
},
Response.ErrorListener {
Toast.makeText(this, "That didn't work!", Toast.LENGTH_SHORT).show()
}){
#Throws(AuthFailureError::class)
override fun getHeaders(): MutableMap<String, String> {
val headers = HashMap<String, String>()
headers.put("Accept", "application/json")
headers.put("Content-Type", "application/json; charset=utf-8")
return headers
}
}
queue.add(request)
queue.start()
})
}
Unfortunately I have not figured out a way to add the JWT token into the authorized bearer Header for the next SiteActivity. Any suggestion how to make this work? Should I pass the token directly to the next activity or should I use a singleton? Thanks!

Straightly answering question
Put data into Intent with putExtra("token", token).
Take it on the other side with getIntent().getStringExtra("token").
But...
You may want to save token persistently. For example, into SharedPreferences.