Django Channels equivalent code for javax.websocket - python

I am new to Django Channels. I am trying to replicate what is being done in this Java code using Django Channels. But I cannot figure out how to send the message JSON to the Angular frontend.
The frontend has a table that will get updated throught the websocket implementation. But the recieve method doesn't seem to replicate what the onMessage method was doing. Django Channels performs a successful handshake. But that's all that happens.
Java Code
#ServerEndpoint("/socket/order")
#ApplicationScoped
public class OrderSocket {
Set<Session> sessions = new HashSet<>();
#OnOpen
public void onOpen(Session session) {
LOG.debug("onOpen " + session.getId());
sessions.add(session);
}
#OnClose
public void onClose(Session session) {
LOG.debug("onClose " + session.getId());
sessions.remove(session);
}
#OnError
public void onError(Session session, Throwable throwable) {
LOG.debug("onError " + session.getId() + " left on error: " + throwable);
sessions.remove(session);
}
#OnMessage
public void onMessage(String message) {
LOG.debug("onMessage " + message);
broadcast(message);
}
public void broadcast(OrderDto orderDto) {
Jsonb jsonb = JsonbBuilder.create();
String jsonString = jsonb.toJson(orderDto);
broadcast(jsonString);
}
private void broadcast(String message) {
sessions.forEach(s -> {
LOG.debug("Message broadcasted: " + message);
s.getAsyncRemote().sendObject(message, result -> {
if (result.getException() != null) {
LOG.error("Unable to send message: " + result.getException());
}
});
});
}
}
Python Code
consumer.py
class OrderConsumer(WebsocketConsumer):
log = logging.getLogger('main')
def connect(self):
self.log.debug("onOpen")
self.accept()
def receive(self, text_data=None, bytes_data=None):
self.log.debug("onMessage " + text_data)
self.send(text_data="Message = " + text_data)
def disconnect(self, code):
self.log.debug("onClose")
return super().disconnect(code)
Typescript code
export class OrderWebSocketService {
private API_URL = environment.API_URL;
private SOCKET_URL = this.API_URL.replace(/http/gi, "ws");
myWebSocket: WebSocketSubject<Order> = webSocket(this.SOCKET_URL + 'socket/order/');
constructor(private snackBar: MatSnackBar) { }
public connect(): Observable<Order> {
return this.myWebSocket.asObservable().pipe(
map((obj) => obj),
catchError((error) => this.errorHandler(error))
);
}
public close(): void {
this.myWebSocket.complete();
}
errorHandler(e: any): Observable<any> {
this.showMessage('Something wrong happened with websocket!', true);
return EMPTY;
}
showMessage(msg: string, isError: boolean = false): void {
this.snackBar.open(msg, 'X', {
duration: 3000,
horizontalPosition: "right",
verticalPosition: "top",
panelClass: isError ? ['msg-error'] : ['msg-success']
});
}
}
Would appreciate any suggestions.

Related

Why Python print statements does not show up until the application is completed (in C# service)?

I have a little complex code developed using Python 3.8.10 for image processing. This code is interfaced with C# GUI using "Process()" method.
The code is working but the issue is that all my status updates (print statements) in Python do not show up until the end of the code.
For example in python_code.py,
print(f"Loading model {model_name}, please wait......"
......
......
print(f"Inference completed, loading next image, ......")
......
......
C# code is as follows :
public void AI_SJV_run(string ImageFile, RawBGAXrayParameterFiles AI_Recipe)
{
// https://medium.com/emoney-engineering/running-python-script-from-c-and-working-with-the-results-843e68d230e5
// https://www.tensorflow.org/hub/tutorials/image_retraining
MessageEventArgs e = new MessageEventArgs();
e.message = #"<<<<<<< Script initiaited, please wati.... >>>>>>>";
ProcessStartInfo start = new ProcessStartInfo();
Process process = new Process();
//start.FileName = (Params.Xray_file.DetectionParameters.Algorythm == SJWalgorythm.CONTOUR) ? ContourPython : CirclePython;
//string pythonFile = string.Format("{0}\\{1}.py", PythonAlgorythmFolder, AI_Recipe.Xray_file.DetectionParameters.PythonAlgorythm);
string pythonFile = SJV_Inference_code;
// if (File.Exists(pythonFile))
start.FileName = pythonEXEPath;
if (File.Exists(pythonFile))
{
if (File.Exists(start.FileName))
{
string pythonParams = "";
// AI_Recipe.Xray_file.DetectionParameters.imageParameters is empty for AI recipe
string ParameterName = AI_Recipe.Xray_file.DetectionParameters.PythonAlgorythm;
pythonParams = pythonParams + string.Format("{0} \"{1}\" ", "--AI_Recipe", ParameterName);
string arg = String.Format("--ImageFolder \"{0}\" {1}", ImageFile, pythonParams);
start.Arguments = string.Format("\"{0}\" {1}", pythonFile, arg);
log.Write("Python file : " + start.FileName + "Python parameters >>> " + start.Arguments);
m.message = start.Arguments;
sendPythonMessage(this, m);
sendPythonMessage(this, e);
start.UseShellExecute = false;
start.CreateNoWindow = true;
start.RedirectStandardOutput = !start.UseShellExecute;
start.RedirectStandardError = !start.UseShellExecute;
process.StartInfo = start;
process.EnableRaisingEvents = true;
process.OutputDataReceived += SJW_Output;
process.ErrorDataReceived += SJW_Error;
process.Exited += new EventHandler(SJW_Exited);
process.Start();
process.BeginOutputReadLine();
process.BeginErrorReadLine();
process.WaitForExit();
}
else
{
m.message = "Python executable not found : " + start.FileName;
sendPythonMessage(this, m);
}
}
else
{
m.message = "Algorythm file not found : " + pythonFile;
sendPythonMessage(this, m);
}
}
public void AI_SJV_Output(object sender, DataReceivedEventArgs e)
{
try
{
string results = e.Data;
if (results != null)
{
m.message = results;
}
}
catch (Exception ex)
{
m.message = "ERROR # SJW_Output : " + ex.Message + "EXCEMPTION : " + ex.InnerException;
}
sendPythonMessage(this, m);
}
private void AI_SJV_Error(object sender, DataReceivedEventArgs e)
{
string ErrorResult = e.Data;
if (ErrorResult != null)
{
try
{
m.message = "SJW Error :" + ErrorResult;
}
catch (Exception ex)
{
m.message = "ERROR # SJW_Error : " + ErrorResult + " " + ex.Message + "EXCEMPTION : " + ex.InnerException;
}
sendPythonMessage(this, m);
}
}
private void AI_SJV_Exited(object sender, EventArgs e)
{
Bumps bumps = new Bumps();
try
{
m.message = "<<<<<<< Script completed >>>>>>>";
}
catch (Exception ex)
{
m.message = "ERROR # SJQ_Exited : " + ex.Message + "EXCEMPTION : " + ex.InnerException;
}
sendPythonMessage(this, m);
}
print statements in Python do not trigger "AI_SJV_Output" method until end of the code
But at the end, it dumps all statements ran until then.
Any help?

Android TCP client can't send data to server

I'm doing project with beacon.
smartphone(android client) collect rssi nearby beacons and send to python(server)
< current application's function >
-> when new beacon signal captured, display beacon's rssi value, Mac address
-> connect with tcp and send to python server in real time (Problem!!)
when using method(send text message to python server) with buttonclickevent,
connecting and sending text message works well.
but when i use method with listview adapter(using ArrayMap),
connecting works well, but can't send rssi.
more detail, infinite loop for waiting data
I think there is a problem between using runOnUiThread and data sending but i'm not sure about it.
Mainactivity
package midascon.example.scanlist;
import com.hanvitsi.midascon.Beacon;
import com.hanvitsi.midascon.BeaconCallback;
import com.hanvitsi.midascon.MidasApplication;
import com.hanvitsi.midascon.manager.ContextManager;
import android.Manifest;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.StrictMode;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.widget.ListView;
public class MainActivity extends Activity implements BeaconCallback, Runnable
{
private static final int MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 100;
private ContextManager contextManager;
private BeaconListAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (android.os.Build.VERSION.SDK_INT > 9) { StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); StrictMode.setThreadPolicy(policy); }
checkPermission();
contextManager = getMidasApplication().getContextManager();
contextManager.getBeaconSettings().setMidasScanMode(false);
adapter = new BeaconListAdapter(getBaseContext()); // Beacon list adapter
ListView listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(adapter);
}
#Override
public void onBeaconCallback(int status, Beacon beacon) // add beacon to list when beacon signal captured
{
switch (status) {
case STATUS_CODE_ENTER:
case STATUS_CODE_UPDATE:
if (adapter != null)
adapter.addBeacon(beacon);
break;
case STATUS_CODE_EXIT:
if (adapter != null)
adapter.removeBeacon(beacon);
break;
default:
break;
}
runOnUiThread(this);
}
public void checkPermission() // allow permission
{
if(checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
}
}
#Override
public void run() {
if (adapter != null)
adapter.notifyDataSetChanged();
}
// call name class setting by AndroidManifest.xml
public MidasApplication getMidasApplication() {
return (MidasApplication) getApplication();
}
#Override
protected void onResume() {
super.onResume();
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)) {
ActivityCompat.requestPermissions(this, new String[] { Manifest.permission.ACCESS_FINE_LOCATION }, MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION);
}
else
{
ActivityCompat.requestPermissions(this, new String[] { Manifest.permission.ACCESS_FINE_LOCATION }, MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION);
}
}
else {
if (BluetoothAdapter.getDefaultAdapter().isEnabled()) {
// register callback
contextManager.setBeaconCallback(this);
contextManager.startLeScan();
} else {
contextManager.stopLeScan();
Intent settingsIntent = new Intent(android.provider.Settings.ACTION_BLUETOOTH_SETTINGS);
startActivity(settingsIntent);
}
}
}
#Override
protected void onPause() {
super.onPause();
contextManager.stopLeScan();
}
}
midas is company that made beacon
BeaconListAdapter
public class BeaconListAdapter extends BaseAdapter
{
private final LayoutInflater inflater;
private int count; //counting beacon
private final ArrayMap<String, Beacon> itemMap = new ArrayMap<String, Beacon>();
private final int padding;
public int CurBeaconHave = 2;
private Handler mHandler;
public int port = 9999;
public int initcnt = 0;
public int stackcnt = 0;
public int serveractivate = 0;
public int praccnt = 0;
public static String Sendrssi = "";
public Socket socket = null;
public BeaconListAdapter(Context context) {
super();
padding = (int) context.getResources().getDimension(R.dimen.activity_vertical_margin);
this.inflater = LayoutInflater.from(context);
}
public int addBeacon(Beacon beacon) {
synchronized (itemMap) {
itemMap.put(beacon.getMac(), beacon);
count = itemMap.size();
return count;
}
}
public int removeBeacon(Beacon beacon) {
synchronized (itemMap) {
itemMap.remove(beacon.getMac());
count = itemMap.size();
return count;
}
}
#Override
public int getCount() {
return count;
}
#Override
public Beacon getItem(int position) {
synchronized (itemMap) {
return itemMap.valueAt(position);
}
}
void ToPython() {
try {
String tmp = Sendrssi;
PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())));
out.println(tmp);
out.flush();
Log.d("sendrssi ",tmp);
}
catch (Exception e) {
e.printStackTrace();
}
}
/*public void ToPython() {
try {
String tmp = Sendrssi;
BufferedWriter out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
out.write(tmp);
out.newLine();
out.flush();
Log.d("Sending. Rssi : ", tmp);
} catch (Exception e) {
e.printStackTrace();
}
}*/
void connect() {
Log.w("state", "connecting..");
Thread checkUpdate = new Thread() {
public void run() {
String newip = "192.168.0.4";
try {
socket = new Socket(newip, port);
Log.w("state ", "server connected");
serveractivate = 1;
} catch (IOException e1) {
Log.w("state ", "failed");
e1.printStackTrace();
System.out.println("error :" + e1.getMessage());
}
}
};
checkUpdate.start();
}
#Override
public long getItemId(int position) {
return position;
}
public void stopsocket()
{
try
{
socket.close();
} catch (IOException e){
e.printStackTrace();
}
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView textView = null;
if (convertView == null)
{
convertView = inflater.inflate(android.R.layout.simple_list_item_1, parent, false);
textView = (TextView) convertView.findViewById(android.R.id.text1);
textView.setBackgroundColor(Color.WHITE);
textView.setTextColor(Color.BLACK);
textView.setPadding(padding, padding, padding, padding);
convertView.setTag(textView);
}
else
{
textView = (TextView) convertView.getTag();
}
Beacon item = getItem(position);
int temprssi = item.getRssi();
while(serveractivate == 0)
{
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
Log.d("Connect State : ","wait for Server Connect...");
connect();
}
if(serveractivate == 1)
{
try {
socket.setTcpNoDelay(true);
} catch (SocketException e) {
e.printStackTrace();
}
}
int[] values = BeaconUtils.getAccelerometer(item);
textView.setText(String.format("[%s]\nMAC : %s\nRssi : %d\n", item.getType() == Beacon.TYPE_MIDAS ? "Midascon" : "Beacon", item.getMac(),temprssi));
if(count == CurBeaconHave)
{
if(stackcnt == CurBeaconHave)
{
ToPython();
stackcnt = 0;
Sendrssi = "";
}
else if(stackcnt != CurBeaconHave)
{
Sendrssi = Sendrssi + temprssi + " " ;//+ (temprssi - 3) + " " + (temprssi + 5) + " " + (temprssi - 7) + " ";
stackcnt++;
}
}
return convertView;
}
}
total code line is about 400 line, so i upload code that have problem i think.
thank you for reading and try to solve my problem
if you need another code i'll upload it
Note that i'm not good at english, so you may have difficult with reading and understand. sorry for that :(
problem solved.
It's not a normal method, so please be patient.
BeaconListadapter in connect method, i use thread.
but i don't use thread in Topython method.
because of this, there's problem with socket information when send data
so i delete thread in connect method and run and method
in main thread(i know this is idiot thing)
if you use like me, probably use connect and send data method in one thread

How to send the "token" as a header from a GUI application to at GET command in a flask service? [duplicate]

I have an HttpClient that I am using for a REST API. However I am having trouble setting up the Authorization header. I need to set the header to the token I received from doing my OAuth request.
I saw some code for .NET that suggests the following,
httpClient.DefaultRequestHeaders.Authorization = new Credential(OAuth.token);
However the Credential class does that not exist in WinRT. Anyone have any ideas how to set the Authorization header?
So the way to do it is the following,
httpClient.DefaultRequestHeaders.Authorization =
new AuthenticationHeaderValue("Bearer", "Your Oauth token");
request.DefaultRequestHeaders.Authorization =
new AuthenticationHeaderValue(
"Basic", Convert.ToBase64String(
System.Text.ASCIIEncoding.ASCII.GetBytes(
$"{yourusername}:{yourpwd}")));
I look for a good way to deal with this issue and I am looking at the same question. Hopefully, this answer will be helping everyone who has the same problem likes me.
using (var client = new HttpClient())
{
var url = "https://www.theidentityhub.com/{tenant}/api/identity/v1";
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + accessToken);
var response = await client.GetStringAsync(url);
// Parse JSON response.
....
}
reference from https://www.theidentityhub.com/hub/Documentation/CallTheIdentityHubApi
As it is a good practice to reuse the HttpClient instance, for performance and port exhaustion problems, and because none of the answers give this solution (and even leading you toward bad practices :( ), I put here a link towards the answer I made on a similar question :
https://stackoverflow.com/a/40707446/717372
Some sources on how to use HttpClient the right way:
https://aspnetmonsters.com/2016/08/2016-08-27-httpclientwrong/
https://blogs.msdn.microsoft.com/alazarev/2017/12/29/disposable-finalizers-and-httpclient/
I suggest to you:
HttpClient.DefaultRequestHeaders.Add("Authorization", "Bearer <token>");
And then you can use it like that:
var response = await client.GetAsync(url);
if (response.IsSuccessStatusCode)
{
responseMessage = await response.Content.ReadAsAsync<ResponseMessage>();
}
In the case you want to send HttpClient request with Bearer Token, this code can be a good solution:
var requestMessage = new HttpRequestMessage
{
Method = HttpMethod.Post,
Content = new StringContent(".....", Encoding.UTF8, "application/json"),
RequestUri = new Uri(".....")
};
requestMessage.Headers.Authorization = new AuthenticationHeaderValue("Bearer", "Your token");
var response = await _httpClient.SendAsync(requestMessage);
I was setting the bearer token
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
It was working in one endpoint, but not another. The issue was that I had lower case b on "bearer". After change now it works for both api's I'm hitting. Such an easy thing to miss if you aren't even considering it as one of the haystacks to look in for the needle.
Make sure to have "Bearer" - with capital.
Use Basic Authorization And Json Parameters.
using (HttpClient client = new HttpClient())
{
var request_json = "your json string";
var content = new StringContent(request_json, Encoding.UTF8, "application/json");
var authenticationBytes = Encoding.ASCII.GetBytes("YourUsername:YourPassword");
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(authenticationBytes));
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var result = await client.PostAsync("YourURL", content);
var result_string = await result.Content.ReadAsStringAsync();
}
For anyone finding this old thread now (2021), please look at this documentation about HttpClientFactory which is injectable and will also re-run on each request avoiding expired tokens which will make it useful for bearer tokens, generated clients, pooling etc.
TL;DR: Use HttpClientFactory and a DelegatingHandler which will act as middleware on all outgoing requests with your configured client.
This is how I add my bearer for Azure Identity (managed by Azure) but you can get the token however you want of course;
using Microsoft.Azure.Services.AppAuthentication;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
public class BearerTokenHandler : DelegatingHandler
{
public BearerTokenHandler(AzureServiceTokenProvider tokenProvider, string resource)
{
TokenProvider = tokenProvider;
Resource = resource;
}
public AzureServiceTokenProvider TokenProvider { get; }
public string Resource { get; }
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
if (!request.Headers.Contains("Authorization"))
{
// Fetch your token here
string token = await TokenProvider.GetAccessTokenAsync(Resource);
request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", token);
}
return await base.SendAsync(request, cancellationToken);
}
}
I configure my typed clients (generated with NSwag) like this in Startup;
var accessTokenProvider = new AzureServiceTokenProvider("<your-connection-string-for-access-token-provider>");
builder.Services.AddHttpClient<IOrdersClient, OrdersClient>().ConfigureHttpClient(async conf =>
{
conf.BaseAddress = new Uri("<your-api-base-url>");
}).AddHttpMessageHandler(() => new BearerTokenHandler(accessTokenProvider, "https://your-azure-tenant.onmicrosoft.com/api"));
Then you can inject your IOrdersClient wherever you like and all requests will have the bearer.
If you want to reuse the HttpClient, it is advised to not use the DefaultRequestHeaders as they are used to send with each request.
You could try this:
var requestMessage = new HttpRequestMessage
{
Method = HttpMethod.Post,
Content = new StringContent("...", Encoding.UTF8, "application/json"),
RequestUri = new Uri("...")
};
requestMessage.Headers.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(System.Text.ASCIIEncoding.ASCII.GetBytes($"{user}:{password}")));
var response = await _httpClient.SendAsync(requestMessage);
To set basic authentication with C# HttpClient. The following code is working for me.
using (var client = new HttpClient())
{
var webUrl ="http://localhost/saleapi/api/";
var uri = "api/sales";
client.BaseAddress = new Uri(webUrl);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.ConnectionClose = true;
//Set Basic Auth
var user = "username";
var password = "password";
var base64String =Convert.ToBase64String( Encoding.ASCII.GetBytes($"{user}:{password}"));
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",base64String);
var result = await client.PostAsJsonAsync(uri, model);
return result;
}
This is how i have done it:
using (HttpClient httpClient = new HttpClient())
{
Dictionary<string, string> tokenDetails = null;
var messageDetails = new Message { Id = 4, Message1 = des };
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("http://localhost:3774/");
var login = new Dictionary<string, string>
{
{"grant_type", "password"},
{"username", "sa#role.com"},
{"password", "lopzwsx#23"},
};
var response = client.PostAsync("Token", new FormUrlEncodedContent(login)).Result;
if (response.IsSuccessStatusCode)
{
tokenDetails = JsonConvert.DeserializeObject<Dictionary<string, string>>(response.Content.ReadAsStringAsync().Result);
if (tokenDetails != null && tokenDetails.Any())
{
var tokenNo = tokenDetails.FirstOrDefault().Value;
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + tokenNo);
client.PostAsJsonAsync("api/menu", messageDetails)
.ContinueWith((postTask) => postTask.Result.EnsureSuccessStatusCode());
}
}
}
This you-tube video help me out a lot. Please check it out.
https://www.youtube.com/watch?v=qCwnU06NV5Q
6 Years later but adding this in case it helps someone.
https://www.codeproject.com/Tips/996401/Authenticate-WebAPIs-with-Basic-and-Windows-Authen
var authenticationBytes = Encoding.ASCII.GetBytes("<username>:<password>");
using (HttpClient confClient = new HttpClient())
{
confClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(authenticationBytes));
confClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue(Constants.MediaType));
HttpResponseMessage message = confClient.GetAsync("<service URI>").Result;
if (message.IsSuccessStatusCode)
{
var inter = message.Content.ReadAsStringAsync();
List<string> result = JsonConvert.DeserializeObject<List<string>>(inter.Result);
}
}
UTF8 Option
request.DefaultRequestHeaders.Authorization =
new AuthenticationHeaderValue(
"Basic", Convert.ToBase64String(
System.Text.Encoding.UTF8.GetBytes(
$"{yourusername}:{yourpwd}")));
Using AuthenticationHeaderValue class of System.Net.Http assembly
public AuthenticationHeaderValue(
string scheme,
string parameter
)
we can set or update existing Authorization header for our httpclient like so:
httpclient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", TokenResponse.AccessToken);
BaseWebApi.cs
public abstract class BaseWebApi
{
//Inject HttpClient from Ninject
private readonly HttpClient _httpClient;
public BaseWebApi(HttpClient httpclient)
{
_httpClient = httpClient;
}
public async Task<TOut> PostAsync<TOut>(string method, object param, Dictionary<string, string> headers, HttpMethod httpMethod)
{
//Set url
HttpResponseMessage response;
using (var request = new HttpRequestMessage(httpMethod, url))
{
AddBody(param, request);
AddHeaders(request, headers);
response = await _httpClient.SendAsync(request, cancellationToken);
}
if(response.IsSuccessStatusCode)
{
return await response.Content.ReadAsAsync<TOut>();
}
//Exception handling
}
private void AddHeaders(HttpRequestMessage request, Dictionary<string, string> headers)
{
request.Headers.Accept.Clear();
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
if (headers == null) return;
foreach (var header in headers)
{
request.Headers.Add(header.Key, header.Value);
}
}
private static void AddBody(object param, HttpRequestMessage request)
{
if (param != null)
{
var content = JsonConvert.SerializeObject(param);
request.Content = new StringContent(content);
request.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
}
}
SubWebApi.cs
public sealed class SubWebApi : BaseWebApi
{
public SubWebApi(HttpClient httpClient) : base(httpClient) {}
public async Task<StuffResponse> GetStuffAsync(int cvr)
{
var method = "get/stuff";
var request = new StuffRequest
{
query = "GiveMeStuff"
}
return await PostAsync<StuffResponse>(method, request, GetHeaders(), HttpMethod.Post);
}
private Dictionary<string, string> GetHeaders()
{
var headers = new Dictionary<string, string>();
var basicAuth = GetBasicAuth();
headers.Add("Authorization", basicAuth);
return headers;
}
private string GetBasicAuth()
{
var byteArray = Encoding.ASCII.GetBytes($"{SystemSettings.Username}:{SystemSettings.Password}");
var authString = Convert.ToBase64String(byteArray);
return $"Basic {authString}";
}
}
In net .core you can use with Identity Server 4
var client = new HttpClient();
client.SetBasicAuthentication(userName, password);
or
var client = new HttpClient();
client.SetBearerToken(token);
see https://github.com/IdentityModel/IdentityModel/blob/main/src/Client/Extensions/AuthorizationHeaderExtensions.cs
this could works, if you are receiving a json or an xml from the service and i think this can give you an idea about how the headers and the T type works too, if you use the function MakeXmlRequest(put results in xmldocumnet) and MakeJsonRequest(put the json in the class you wish that have the same structure that the json response) in the next way
/*-------------------------example of use-------------*/
MakeXmlRequest<XmlDocument>("your_uri",result=>your_xmlDocument_variable = result,error=>your_exception_Var = error);
MakeJsonRequest<classwhateveryouwant>("your_uri",result=>your_classwhateveryouwant_variable=result,error=>your_exception_Var=error)
/*-------------------------------------------------------------------------------*/
public class RestService
{
public void MakeXmlRequest<T>(string uri, Action<XmlDocument> successAction, Action<Exception> errorAction)
{
XmlDocument XMLResponse = new XmlDocument();
string wufooAPIKey = ""; /*or username as well*/
string password = "";
StringBuilder url = new StringBuilder();
url.Append(uri);
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url.ToString());
string authInfo = wufooAPIKey + ":" + password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
request.Timeout = 30000;
request.KeepAlive = false;
request.Headers["Authorization"] = "Basic " + authInfo;
string documento = "";
MakeRequest(request,response=> documento = response,
(error) =>
{
if (errorAction != null)
{
errorAction(error);
}
}
);
XMLResponse.LoadXml(documento);
successAction(XMLResponse);
}
public void MakeJsonRequest<T>(string uri, Action<T> successAction, Action<Exception> errorAction)
{
string wufooAPIKey = "";
string password = "";
StringBuilder url = new StringBuilder();
url.Append(uri);
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url.ToString());
string authInfo = wufooAPIKey + ":" + password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
request.Timeout = 30000;
request.KeepAlive = false;
request.Headers["Authorization"] = "Basic " + authInfo;
// request.Accept = "application/json";
// request.Method = "GET";
MakeRequest(
request,
(response) =>
{
if (successAction != null)
{
T toReturn;
try
{
toReturn = Deserialize<T>(response);
}
catch (Exception ex)
{
errorAction(ex);
return;
}
successAction(toReturn);
}
},
(error) =>
{
if (errorAction != null)
{
errorAction(error);
}
}
);
}
private void MakeRequest(HttpWebRequest request, Action<string> successAction, Action<Exception> errorAction)
{
try{
using (var webResponse = (HttpWebResponse)request.GetResponse())
{
using (var reader = new StreamReader(webResponse.GetResponseStream()))
{
var objText = reader.ReadToEnd();
successAction(objText);
}
}
}catch(HttpException ex){
errorAction(ex);
}
}
private T Deserialize<T>(string responseBody)
{
try
{
var toReturns = JsonConvert.DeserializeObject<T>(responseBody);
return toReturns;
}
catch (Exception ex)
{
string errores;
errores = ex.Message;
}
var toReturn = JsonConvert.DeserializeObject<T>(responseBody);
return toReturn;
}
}
}
It may be easier to use an existing library.
For example, the extension methods below are added with Identity Server 4
https://www.nuget.org/packages/IdentityModel/
public static void SetBasicAuthentication(this HttpClient client, string userName, string password);
//
// Summary:
// Sets a basic authentication header.
//
// Parameters:
// request:
// The HTTP request message.
//
// userName:
// Name of the user.
//
// password:
// The password.
public static void SetBasicAuthentication(this HttpRequestMessage request, string userName, string password);
//
// Summary:
// Sets a basic authentication header for RFC6749 client authentication.
//
// Parameters:
// client:
// The client.
//
// userName:
// Name of the user.
//
// password:
// The password.
public static void SetBasicAuthenticationOAuth(this HttpClient client, string userName, string password);
//
// Summary:
// Sets a basic authentication header for RFC6749 client authentication.
//
// Parameters:
// request:
// The HTTP request message.
//
// userName:
// Name of the user.
//
// password:
// The password.
public static void SetBasicAuthenticationOAuth(this HttpRequestMessage request, string userName, string password);
//
// Summary:
// Sets an authorization header with a bearer token.
//
// Parameters:
// client:
// The client.
//
// token:
// The token.
public static void SetBearerToken(this HttpClient client, string token);
//
// Summary:
// Sets an authorization header with a bearer token.
//
// Parameters:
// request:
// The HTTP request message.
//
// token:
// The token.
public static void SetBearerToken(this HttpRequestMessage request, string token);
//
// Summary:
// Sets an authorization header with a given scheme and value.
//
// Parameters:
// client:
// The client.
//
// scheme:
// The scheme.
//
// token:
// The token.
public static void SetToken(this HttpClient client, string scheme, string token);
//
// Summary:
// Sets an authorization header with a given scheme and value.
//
// Parameters:
// request:
// The HTTP request message.
//
// scheme:
// The scheme.
//
// token:
// The token.
public static void SetToken(this HttpRequestMessage request, string scheme, string token);
Firstly, I wouldn't use HttpClient directly. It's too easy to make mistakes - particularly in the area of headers. The DefaultHeadersCollection is not immutable and not thread-safe because other parts of the app can change the headers on you. It's best to set the headers when you make the call. If you are working with an abstraction, and that is recommended because the classes in this area are a bit of a mess, you would want to have a headers collection and put those on your HttpRequestMessage before you send it. You need to make sure you put the content headers on the content, and not the message.
Code Reference
foreach (var headerName in request.Headers.Names)
{
//"Content-Type"
if (string.Compare(headerName, HeadersExtensions.ContentTypeHeaderName, StringComparison.OrdinalIgnoreCase) == 0)
{
//Note: not sure why this is necessary...
//The HttpClient class seems to differentiate between content headers and request message headers, but this distinction doesn't exist in the real world...
//TODO: Other Content headers
httpContent?.Headers.Add(HeadersExtensions.ContentTypeHeaderName, request.Headers[headerName]);
}
else
{
httpRequestMessage.Headers.Add(headerName, request.Headers[headerName]);
}
}
Here is a data structure that you could use to send the request which includes the headers.
Code Reference
public interface IRequest
{
CancellationToken CancellationToken { get; }
string? CustomHttpRequestMethod { get; }
IHeadersCollection Headers { get; }
HttpRequestMethod HttpRequestMethod { get; }
AbsoluteUrl Uri { get; }
}
public interface IRequest<TBody> : IRequest
{
TBody? BodyData { get; }
}
And, a headers collection:
Code Reference
public sealed class HeadersCollection : IHeadersCollection
{
#region Fields
private readonly IDictionary<string, IEnumerable<string>> dictionary;
#endregion
#region Public Constructors
public HeadersCollection(IDictionary<string, IEnumerable<string>> dictionary) => this.dictionary = dictionary;
public HeadersCollection(string key, string value) : this(ImmutableDictionary.CreateRange(
new List<KeyValuePair<string, IEnumerable<string>>>
{
new(key, ImmutableList.Create(value))
}
))
{
}
#endregion Public Constructors
#region Public Properties
public static HeadersCollection Empty { get; } = new HeadersCollection(ImmutableDictionary.Create<string, IEnumerable<string>>());
public IEnumerable<string> Names => dictionary.Keys;
IEnumerable<string> IHeadersCollection.this[string name] => dictionary[name];
#endregion Public Properties
#region Public Methods
public bool Contains(string name) => dictionary.ContainsKey(name);
public IEnumerator<KeyValuePair<string, IEnumerable<string>>> GetEnumerator() => dictionary.GetEnumerator();
IEnumerator IEnumerable.GetEnumerator() => dictionary.GetEnumerator();
public override string ToString() => string.Join("\r\n", dictionary.Select(kvp => $"{kvp.Key}: {string.Join(", ", kvp.Value)}\r\n"));
#endregion
}
See all the working code and examples here.
You can too to use the follow exemple, that it use IHttpClientFactory:
readonly IHttpClientFactory _httpClientFactory;
public HTTPClientHelper(IHttpClientFactory httpClientFactory, string clientName = null)
{
this._httpClientFactory = httpClientFactory;
}
public Task<T> GetAsync(string url, string token) {
var client = _httpClientFactory.CreateClient(_clientName);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(JwtBearerDefaults.AuthenticationScheme, token);
using (HttpResponseMessage response = await _client.GetAsync(url)){
......
}
}
I came across this old thread. The problem I had was that I know to use a static HttpClient, but my token needs refreshing every 59 minutes.
So I could have used HttpClientFactory, but because one of my projects was still in .NET 4.8, I created a class that inherited from HttpClient so I have similar code in all projects. A secret is needed to be able to get the token (I'm using identityserver4).
I then set that as a singleton in DI (I'm using Ninject here):
Bind<MyHttpClient>().ToMethod(c =>
{
var accessKey = ConfigurationManager.AppSettings["AccessKey"];
var client = new MyHttpClient(accessKey)
{
BaseAddress = new Uri(MyUrls.MyApiBaseUrl)
};
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
return client;
}).InSingletonScope();
Then the class itself - named after the API it is used to access:
public class MyHttpClient : BaseHttpClient
{
private static readonly HttpClient _authHttpClient = new HttpClient();
private string _secret;
public MyHttpClient(string secret)
{
_secret = secret;
}
/// <summary>
/// Add the token to each and every request, cached for 1 minute less than the token's lifetime
/// </summary>
/// <param name="request"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
public override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
cancellationToken.ThrowIfCancellationRequested();
var cacheSeconds = 3600 - 60; // Default of 59 minutes
var token = CacheHelper<string>.Get("MyToken", cacheSeconds * 60, () =>
{
var authorityUrl = MyUrls.AuthServerUrl;
// discover endpoints from metadata
DiscoveryDocumentResponse disco;
disco = _authHttpClient.GetDiscoveryDocumentAsync(authorityUrl).Result;
if (disco.IsError)
{
throw new Exception("Error getting discovery document: " + disco.Error);
}
// request token
var tokenResponse = _authHttpClient.RequestClientCredentialsTokenAsync(new ClientCredentialsTokenRequest
{
Address = disco.TokenEndpoint,
ClientId = "myapp",
ClientSecret = _secret,
Scope = "myapi"
}).Result;
if (tokenResponse.IsError)
{
throw new Exception("Error getting token: " + tokenResponse.Error);
}
if (tokenResponse.ExpiresIn < cacheSeconds + 60)
{
throw new Exception($"Token expires in {tokenResponse.ExpiresIn}s, which is less than {cacheSeconds + 60}");
}
if (tokenResponse.ExpiresIn > cacheSeconds + 60)
{
Log.Warn().Message($"Token expiry in {tokenResponse.ExpiresIn}s, which is greater than {cacheSeconds}").Write();
}
return tokenResponse.AccessToken;
});
// THIS IS THE BIT - Assign this inside a SendAsync override and you are done!
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
return base.SendAsync(request, cancellationToken);
}
}
Finally just for completeness, my CacheHelper class looks like this:
public static class CacheHelper<T>
{
private static readonly object _locker = new object();
public static T Get(string cacheName, int cacheTimeoutSeconds, Func<T> func)
{
var obj = MemoryCache.Default.Get(cacheName, null);
if (obj != null) return (T)obj;
lock (_locker)
{
obj = MemoryCache.Default.Get(cacheName, null);
if (obj == null)
{
obj = func();
var cip = new CacheItemPolicy
{
AbsoluteExpiration = new DateTimeOffset(DateTime.UtcNow.AddSeconds(cacheTimeoutSeconds))
};
MemoryCache.Default.Set(cacheName, obj, cip);
}
}
return (T)obj;
}
}
Oauth Process flow is complex and there is always a room for one error or another.
My suggestion will be to always use the boilerplate code and a set of libraries for OAuth authentication flow.It will make your life easier.
Here is the link for the set of libraries.OAuth Libraries for .Net
If you are using Visual Studio IISExpress debug mode and connecting to the HTTP port rather than the HTTPS port you may find that the auth headers are being dropped.
Switch to the SLL connection and they will appear again.
unsure why, possibly the setup redirects the http traffic and that causes the auth to be removed.
This may help Setting the header:
WebClient client = new WebClient();
string authInfo = this.credentials.UserName + ":" + this.credentials.Password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
client.Headers["Authorization"] = "Basic " + authInfo;
static async Task<AccessToken> GetToken()
{
string clientId = "XXX";
string clientSecret = "YYY";
string credentials = String.Format("{0}:{1}", clientId, clientSecret);
using (var client = new HttpClient())
{
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", Convert.ToBase64String(Encoding.UTF8.GetBytes(credentials)));
List<KeyValuePair<string, string>> requestData = new List<KeyValuePair<string, string>>();
requestData.Add(new KeyValuePair<string, string>("grant_type", "client_credentials"));
FormUrlEncodedContent requestBody = new FormUrlEncodedContent(requestData);
var request = await client.PostAsync("https://accounts.spotify.com/api/token", requestBody);
var response = await request.Content.ReadAsStringAsync();
return JsonConvert.DeserializeObject<AccessToken>(response);
}
}

amazonmq invoke aws lambda

AWS CloudWatch Events to trigger a Lambda function that polls for messages on a queue. Messages are then sent to a second Lambda function that writes the message to an Kinesis agent.
I found a solution to this article but written in node.js. But I am looking for Python script. Could you please help me to get a article where I can find a way to convert it by myself.
https://github.com/aws-samples/amazonmq-invoke-aws-lambda
const stomp = require('stompit')
const AWS = require('aws-sdk')
let lambda = new AWS.Lambda()
const QUEUE_NAME = process.env.QUEUE_NAME
const CONNECTION_OPTIONS = {
host: process.env.HOST,
port: 61614,
ssl: true,
connectHeaders: {
login: process.env.LOGIN,
passcode: process.env.PASSWORD
}
}
exports.handler = (event, context, callback) => {
var client
/* */
const onError = (error) => {
console.error(`[ERROR] ${error}`)
callback(error)
}
/* */
const onMessage = (error, message) => {
console.log('Message received')
message.readString('utf-8', (error, body) => {
if (error) {
onError(error)
return
}
let payload = {
message: body,
timestamp: Date.now()
}
console.log(payload)
let params = {
FunctionName: process.env.WORKER_FUNCTION,
Payload: JSON.stringify(payload)
}
lambda.invoke(params, (error, data) => {
if (error) {
console.error(`Could not invoke Lambda: ${error}`)
}
})
})
}
/* Main */
stomp.connect(CONNECTION_OPTIONS, (error, client) => {
if (error) {
onError(error)
return
}
var headers = {
destination: `/queue/${QUEUE_NAME}`,
ack: 'auto'
}
client.subscribe(headers, onMessage)
setTimeout(() => {
client.disconnect()
callback(null, { 'message': 'Finished' })
}, context.getRemainingTimeInMillis() - 1000)
})
}
You don't make it clear what you are trying to achieve, how far you got to, and what issue you are facing.
You can improve your question by following the the SO guidelines.
The library to interact with AWS services in python(3) is boto3.

cv2 incorrect image decode

I'm programming a Java client which sends an image as byte array and a Python server to receive the image. Received image height, width, channels are right,
sock = socket.socket()
sock.bind(('localhost', 8080))
sock.listen(1)
print ("Listen")
conn, addr = sock.accept()
print('Start server')
while True:
data = conn.recv(1024)
if not data:
break
img = cv2.imdecode(np.fromstring(io.BytesIO(data).getvalue(), dtype=np.uint8), 1)
np.save('snapshot.npy',img)
exit()
Showing the image using cv2.imshow('img', img) gives an incorrect result:
Java side:
public class Client implements Runnable {
private Socket socket;
private DataOutputStream out;
private String server;
private int port;
private ArrayList<ResponseListener> listeners = new ArrayList<>();
public void addListener(ResponseListener responseListener){
listeners.add(responseListener);
}
public void removeListeners(ResponseListener responseListener){
listeners.remove(responseListener);
}
Client(String server, int port) {
this.server = server;
this.port = port;
}
public void start(){
while(socket==null){
try {
socket = new Socket(server, port);
socket.setTcpNoDelay(true);
System.out.println("Ready");
listeners.forEach((listener)->listener.serverIsReady());
} catch (Exception ex) {
System.out.println("In thread " + ex.toString());
}
}
}
public void send(byte[] img) throws IOException {
out.write(img);
}
#Override
public void run() {
InputStreamReader in = null;
try {
in = new InputStreamReader(socket.getInputStream());
System.out.println(in);
out = new DataOutputStream(socket.getOutputStream());
} catch (IOException e) {
System.out.println("in or out failed");
System.exit(-1);
}
int count = 0;
while (true) {
try {
int line = in.read();
count++;
if(count==4) {
listeners.forEach((listener)->listener.onSignDefined(String.valueOf(line)));
count=0;
}
} catch (Exception e) {
System.out.println("In loop " + e.toString());
System.exit(-1);
}
}
}
}
I solved problem. Solution really easy:
data = conn.recv(640*480*3)
640*480*3 - size of image

Categories