Measure bandwidth usage with Apache HttpComponents HttpClient

Question

How can I measure HttpClients bandwidth usage for my app? (HttpComponents 4.3)

I have a client application that is communicating with a server using HttpClient. All requests are done through the same client using a pooling http connection manager. Unfortunately, most of the requests use the httpclient directly (not all of them) so measuring bandwidth at the request location would be doable, but a pain.

Is there a place at either the constructor of the client or the connection manager where I can simply inject my own bandwidth monitor (or is that already built in somewhere that I haven't discovered)?

Can I do it with this?

    HttpClientBuilder.create().addInterceptorLast(new HttpResponseInterceptor()
    {

        @Override
        public void process(HttpResponse response, HttpContext context) throws HttpException, IOException
        {

        }
    }).build();

Answer 1

Custom HttpRequestExecutor should probably the most convenient interception point

This is a very crude solution but I hope is enough to get you started.

final AtomicLong totalBytes = new AtomicLong();

HttpRequestExecutor requestExecutor = new HttpRequestExecutor() {

    @Override
    protected HttpResponse doSendRequest(
            final HttpRequest request,
            final HttpClientConnection conn,
            final HttpContext context) throws IOException, HttpException {
        HttpResponse response = super.doSendRequest(request, conn, context);
        HttpConnectionMetrics metrics = conn.getMetrics();
        totalBytes.addAndGet(metrics.getSentBytesCount());
        metrics.reset();
        return response;
    }

    @Override
    protected HttpResponse doReceiveResponse(
            final HttpRequest request,
            final HttpClientConnection conn,
            final HttpContext context) throws HttpException, IOException {
        HttpResponse response = super.doReceiveResponse(request, conn, context);
        HttpConnectionMetrics metrics = conn.getMetrics();
        totalBytes.addAndGet(metrics.getReceivedBytesCount());
        metrics.reset();
        return response;
    }
};

CloseableHttpClient httpclient = HttpClients
        .custom()
        .setRequestExecutor(requestExecutor)
        .build();

Answer 2

HttpClient client = HttpClients.createDefault();
HttpGet req = new HttpGet("https://www.google.com/");
HttpClientContext hcc = HttpClientContext.create();
HttpResponse res = client.execute(req, hcc);
HttpConnectionMetrics metrics = hcc.getConnection().getMetrics();
EntityUtils.consumeQuietly(res.getEntity());
LOG.debug("sent: {}, recv: {}, reqcnt: {}, rescnt: {}",
        metrics.getSentBytesCount(), metrics.getReceivedBytesCount(),
        metrics.getRequestCount(), metrics.getResponseCount());

HttpConnectionMetrics hold everything you need.