Suppose I have a function which makes a POST request to an HTTP endpoint. I want to encrypt the payload on the client side. Suppose my web app has a function encrypt. I would like to implement the following workflow:
encrpyt(data) {
// do some encrpytion
return encrypted;
}
onPost(data) {
encrypted = encrpyt(data);
post(encrypted, endpoint);
}
My question is: would it be possible for the client to know the encrypt function. I know that over the network the encrpyted data can be seen, but it is possible that there is no way to know the code of the encrypt function on the client side. Also, for the app, data is not directly implemented by the client but rather it is data = data(client_input).
This question has a generalization which is: if I am using a framework like React/Angular, when I compile my app, are source code functions visible to the client?
Related
For my Google Assistant/Dialogflow project, I am trying to intercept every response my firebase-functions endpoint is sending back to Dialogflow. I can easily intercept the request, but the response gets built within several functions (one function for every Intent), and I don't want to include an interceptor in every function.
Is it possible to have a middleware or is there a callback provided when a response is send out, sort of a global interceptor for every response?
I have found the following in the Docs: https://firebase.google.com/docs/functions/http-events#use_middleware_modules_with
However, I am unsure where this goes. Note that I am not using a custom express setup, but I am using the native implementation on firebase directly.
serialize() method is called on conversation right before the response is sent back, so what you can do is to extend the conversation object(based on the library you are using) and overwrite the serialize method to do whatever you need to do. don't forget to call the original serialize method and return the value in your new method.
Since you are using Dialog Flow with Firebase for your fulfilment, I am expecting you are also using actions-on-google package.
serialize() is a function which is called to generate the response. You can override this function and intercept the request and response. Try this code and thank me later. 😉
app.middleware((conv) => {
const serializeCopy = conv.serialize;
conv.serialize = () => {
const response = serializeCopy.call(conv);
console.log(conv.request, response);
return response;
};
});
Cloud Functions does not expose any sort of middleware or interceptors for HTTP requests or responses. You will have to build something yourself, probably with an Express app that you build yourself. You can host an Express app on Cloud Functions.
I wanted something similar to intercept all conversations back and forth for logging purposes. I ended up writing a function that I use to send a conversation. For eg:
const intercept = (conv, sentence) => {
//My Interceptor code
conv.ask(sentence)
}
Now anytime I want to send a response, I would use:
intercept(conv, "Speak this")
I am trying to make a reques to API Gateway with the AWS SDK for .NET but I have no idea how to do that. The documentation is very lacking and there are no examples posted online of it.
This is as far as I've gotten so far:
const String awsAccessKeyId = "43789hf872hy832h"; // Get access key from a secure store
const String awsSecretAccessKey = "4738fbdhskjfy932hjk"; // Get secret key from a secure store
var client = new AmazonAPIGatewayClient(awsAccessKeyId, awsSecretAccessKey,RegionEndpoint.USEast1);
But I don't know how to make a get request to one of my APIs.
Does anyone have any experience dealing with this?
The AmazonApiGatewayClient isn't meant for invoking your API's, but rather a client for managing your ApiGateway resources. If you would like to invoke your endpoints, you should be using an HTTP client for this.
Here is one you can use from within C#, but you can also use your browser, or a tool like Postman or Fiddler.
So now that Angular 2 is in beta I have been using observables on the client side and I have been using ASP.NET Core Web API on the server side. My question is if I want to display a value on my website as that value changes I understand how to do it on the client side with Observables, but how do I use Observables with a Web API service on the server?
Thanks for your time....
If I understand your question correcly, you can use Refit , to generate the implementation of an interface that returns an IObservable from a REST API.
For the example below, an interface is declared for the /users/{user} REST API. The return type is an IObservable and when you compile this, Refit generates the implementation.
public interface IRestAPI
{
// Returns the raw response, as an IObservable that can be used with the
// Reactive Extensions
[Get("/users/{user}")]
IObservable<HttpResponseMessage> GetUser(string user);
}
To initialize it, you do something like this:
var api = RestService.For<IRestAPI>("http://api.example.com/users");
I have a web application which has few charts on dashboard. The data for charts is fetched on document.ready function at client side invoking a WCF service method.
What i want is now to use SignalR in my application. I am really new to SignalR. How can i call WCF methods from SignalR Hub or what you can say is that instead of pulling data from server i want the WCF service to push data to client every one minute.
Is there a way of communication between signalR and WCF service.
Also another approach can be to force client to ask for data from WCF Service every minute.
Any help will be really appreciated.
I have done following as of yet.
Client Side Function on my Dashboard page
<script src="Scripts/jquery.signalR-2.0.3.min.js"></script>
<!--Reference the autogenerated SignalR hub script. -->
<script src="/signalr/hubs"></script>
<a id="refresh">Refresh</a>
$(function() {
var dashboardHubProxy = $.connection.dashboardHub;
$.connection.hub.start().done(function() {
// dashboardHubProxy.server.refreshClient(parameters);
$("#refresh").click(function() {
dashboardHubProxy.server.refreshClient(parameters);
});
});
dashboardHubProxy.client.refreshChart = function (chartData) {
debugger;
DrawChart(chartData, 'Hourly Call Count For Last ' + Duration + ' Days', '#chartHourly', 'StackedAreaChart');
};
});
and my Dashboard Hub class is as follows
public class DashboardHub : Hub
{
private readonly ReportService ReportService = new ReportService();
public void RefreshClient(string parameters)
{
var chartData = ReportService.GenerateHourlyCallsTrendGraphicalReport(parameters);
Clients.All.refreshChart(chartData);
}
}
My SignalR startup class is as follows
[assembly: OwinStartup(typeof(CallsPortalWeb.Startup), "Configuration")]
namespace CallsPortalWeb
{
public static class Startup
{
public static void Configuration(IAppBuilder app)
{
ConfigureSignalR(app);
}
public static void ConfigureSignalR(IAppBuilder app)
{
app.MapSignalR();
}
}
}
When i click on refresh button and a debugger on RefreshClient method on hub the debugger doesn't get to the method which means i am unable to call server side method of SignalR.
Is there anything needs to be done in web.config?
I agree with AD.Net's comment. To elaborate slightly more though, the SignalR hubs can be hosted directly in your web project kinda the same way controllers are used. There is also a package out there so you can host the SignalR library on its own so it can act as a service all on its own. Either way you will need to hit the SignalR hub first as that is how it communicates then you would call your WCF service methods from within the hubs.
Brief explanation
Your HUB will have methods used by both your USER Client and your WCF Client. You may use something like UserConnected() for the user to call in and setup your logging of the connection. Then the WCF service may call your HUB with an UpdateUserStats(Guid connnectionId, UserStats stats) which would in turn call the USER client directly and provide the stats passed in like so Clients.Client(connectionId).updateStats(stats) which in turn would have a method on the USERS client named updateStats() that would handle the received information.
Initial page landing
What AD.Net provided is basic code that will be called when the user lands on the page. At this point you would want to log the ConnectionId related to that user so you can directly contact them back.
First contact with your hub touching WCF
From your Hub, you could call your WCF service as you normally would inside any normal C# code to fetch your data or perform action and return it to your user.
Method of updating the user periodically
SignalR removes the need for your client code to have to continually poll the server for updates. It is meant to allow you to push data out to the client with out them asking for it directly. This is where the persistence of the connections come into play.
You will probably want to create a wrapper to easily send messages to the hub from your application, since you are using WCF I would assume you have your business logic behind this layer so you will want the WCF service reaching out to your Hub whenever action X happens. You can do that by utilizing the Client side C# code as in this case your client is actually the user and the WCF service. With a chat application the other user is basically doing what you want your WCF service to do, which is send a message to the other client.
Usage example
You are running an online store. The dashboard displays how many orders there have been for the day. So you would wire up a call to the hub to send a message out to update the products ordered when a user places a new order. You can do this by sending it to the admin group you have configured and any admins on the dashboard would get the message. Though if these stats are very user specific, you will more then likely instead reach into the database, find the ConnectionId that the user has connected with and send the update message directly to that connectionid.
WCF Client Code Example
Just incase you want some code, this is directly from MS site on connecting with a .net client. You would use this in your WCF service, or wherever in your code you plan on connecting and then sending an update to your user.
var hubConnection = new HubConnection("http://www.contoso.com/");
IHubProxy stockTickerHubProxy = hubConnection.CreateHubProxy("StockTickerHub");
stockTickerHubProxy.On<Stock>("UpdateStockPrice", stock => Console.WriteLine("Stock update for {0} new price {1}", stock.Symbol, stock.Price));
await hubConnection.Start();
Here is a link directly to the .Net Client section: http://www.asp.net/signalr/overview/signalr-20/hubs-api/hubs-api-guide-net-client
I am sure you have seen this link but it really holds all the good information you need to get started. http://www.asp.net/signalr
Here is a more direct link that goes into usages with code for you. http://www.asp.net/signalr/overview/signalr-20/hubs-api/hubs-api-guide-server
ADDED: Here is a blog specific to Dashboards with SignalR and their polling.
http://solomon-t.blogspot.com/2012/12/signalr-and-interval-polling-for.html
ADDED: Here is a page on managing users signalR connections.
http://www.asp.net/signalr/overview/signalr-20/hubs-api/mapping-users-to-connections
Update for your code update
The .Net Client library (in NuGet) gives your .net code access to the hub. Since you are a client you will need to connect to the hub just like the User who is also a client. Your hub would act as the server for this. So with the .Net Client I am assuming you would setup a windows service that would internally poll, or something event based that would call the .Net Client code portion of it which would reach out to your hub. Your hub would take the information provided, more than likely a ConnectionId or GroupId and broad cast the User (which is perhaps on a website so it would be the JS client) a method that would update the front end for the user client. Basically what I mention under "Brief Explanation".
Now, to directly respond to the code you posted. That is Javascript, I would expect a connect like you have done. Updating the chart on initial connection is fine as well. If this is all the code signalR wise though you are missing a client side method to handle the refresh. Technically, instead of calling Clients.Caller.RefreshChart() you could just return that data and use it, which is what your javascript is doing right now. You are returning void but it is expecting a your date.
Now, I would actually say correct your javascript instead of correcting the hub code. Why? Because having a method in JS on your client that is called "refreshChart()" can be reused for when you are having your server reach out and update the client.
So I would recommend, dropping anything that is related to updating the dashboard in your JS done statement. If you want to do a notification or something to the user that is fine but dont update the grid.
Now create a JS client function called "refreshChart", note the lower case R, you can call it with a big R in c# but the js library will lowercase it so when you make the function have it will receive your dashboard information.
Now, on the server polling, or executing on some action, your WCF would call a method on the hub that would be say "UpdateDashboar(connectionId,dashInfo)" and that method would then inside of it call the "refreshChart" just like you are doing in your RefreshClient method, accept instead of doing Clients.Caller you would use Clients.Client(connectionId).refreshChart(chartInfo).
Directly the reason your code is not working is because you need to turn that Void into the type you expect to be returned. If the rest is coded right you will have it update once. You will need to implement the other logic I mentioned if you want it constantly updating. Which is again why I asked about how you are persisting your connections. I added a link to help you with that if you are not sure what I am talking about.
You should use the SignalR Hub to push data to the client. Your hub can consume a WCF service (the same way your client can) to get the data.
from client:
hub.VisitingDashBoard();
on the hub in the VisitingDashBoard method:
var data = wcfClient.GetDashboardData()//may be pass the user id from the context
Clients.Caller.UpdateDashboard(data)
Of course your client will have a handler for UpdateDashboard call
I have a Tomcat service running on localhost:8080 and I have installed BlazeDS. I created and configured a simple hello world application like this...
package com.adobe.remoteobjects;
import java.util.Date;
public class RemoteServiceHandler {
public RemoteServiceHandler()
{
//This is required for the Blaze DS to instantiate the class
}
public String getResults(String name)
{
String result = “Hi ” + name + “, the time is : ” + new Date();
return result;
}
}
With what query string can I invoke RemoteServiceHandler to my Tomcat instance via just a browser? Something like... http://localhost:8080/blazeds/?xyz
Unfortunately you can't. First the requests (and responses) are encoded in AMF and second I believe they have to be POSTs. If you dig through the BlazeDS source code and the Flex SDK's RPC library you can probably figure out what it's sending. But AFAIK this hasn't been documented anywhere else.
I think that AMFX (which is AMF in XML) will work for you, using HTTPChannel instead of AMFChannel.
From http://livedocs.adobe.com/blazeds/1/blazeds_devguide/help.html?content=lcarch_2.html#1073189, Channels and channel sets:
Flex clients can use different channel
types such as the AMFChannel and
HTTPChannel. Channel selection depends
on a number of factors, including the
type of application you are building.
If non-binary data transfer is
required, you would use the
HTTPChannel, which uses a non-binary
format called AMFX (AMF in XML). For
more information about channels, see
Channels and endpoints.
This way you can use simple netcat to send the request.
Not sure how authentication will be handled though, you will probably need do a login using Flash, extract the authentication cookie and then submit it as part of your request.
Please update this thread once you make progress so that we all can learn.