Archive for the ‘Development’ Category.

Linux tools on Windows

If you are like me, you don’t want to be bothered to remember if you are working on a Windows or a Linux box. Things like ls, curl etc, should just work. So if you are missing the Linux tools on Windows and you don’t want to install the heavy Cygwin, then the is an alternative, Gow is a lightweight set of Linux Tools for Windows.

Gow can be found here

DNX .Net WebApi Integration testing

I needed to compare some gRPC round trip numbers to plain .Net WebApi. So the question became how to test WepApi round trips from UnitTest harness.

It’s actually pretty simple if you are using the newer DNX libraries. I’m using the TestHost library to get things done.

From project.json

“System.Net.Http”: “4.0.1-beta-23516”,
“Microsoft.AspNet.TestHost”: “1.0.0-rc1-final”,

The UnitTest itself

    public async void PingTheServerRepeat()
      // Setup client & server
      TestServer server = new TestServer(TestServer.CreateBuilder().UseStartup<Startup>());
      HttpClient client = server.CreateClient();

      // Make a request and check response
      var getResponse = await client.GetAsync(“/api/values/5”);
      var response = await getResponse.Content.ReadAsStringAsync();
      Logger.Log(“web api, response=” + response);

      // Hit the webapi, repeatedly
      Stopwatch watch = Stopwatch.StartNew();
      for (int i = 0; i < Util.Repeat; i++)
        getResponse = await client.GetAsync(“/api/values/” + i);
        response = await getResponse.Content.ReadAsStringAsync();
      Logger.Log($“WepApi, round trips={Util.Repeat}, Execution time, millisec={watch.ElapsedMilliseconds}, average roundtrip=” + ((double)watch.ElapsedMilliseconds / Util.Repeat));
      Logger.Log(“web api, response=” + response);

      // Done, release resources

C# Selenium Integration Tests using Chrome Ghost PhantomJs headless driver

A lot has changed since my last post using Selenium to test web pages. Then you had to install a few things both on the client, browser and server. Today it has been simplified a lot. All you need really is the webdriver and you are in business. You can use the webdriver on your development machine and the server machine as well to run the Selenium tests. In my case I’m using the Ghost-PhanthomJS webdriver as I need to do headless testing ( no GUI ). Since it’s a lot harder to run tests automatically on the server if there is need for GUI, it will complicate things a lot, has to do with security restrictions etc.

Lets take a look at what is needed.
Create a new C# project in VS

Install xUnit Package Manger Console in VS using nuget.
Note I’m specifically using 1.9.2 and 2.0 as I know these two work on the build machine, I had trouble with other version combinations.
PM> Install-Package xunit -Version 1.9.2
Install xUnit VS Runner
PM>Install-Package xunit.runner.visualstudio -Version 2.0.0

Install the Chrome webdriver and libraries
PM> Install-Package WebDriver.ChromeDriver

Install the PhantomJS headless driver and libraries
PM> Install-Package PhantomJS

Then we write the test that will run after the build does the web deployment to the local server. The sample below just loads and checks for the title, then shuts down.

using System;
using Xunit;
using OpenQA.Selenium;
using OpenQA.Selenium.Support.UI;
using OpenQA.Selenium.PhantomJS;

namespace IntegrationTesting

    public class HelloIntegration
        // Proofs that google can be pulled up in the browser and has the right title
        public void GoogleCheckTitle()
            // Init
            IWebDriver driver = new PhantomJSDriver();

            // Test
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(3));
            var title = driver.Title;

            // Proof
            Assert.Equal( “Google”, title);

            // Close down


If you are using TFS you also need to point your build agent to the xUnit runner, in my case I just check it in as part of the project and set it like that.
Path to custom test adapters

That’s all you need, then you can write your own tests to test specific functionality tailored to your needs. Selenium is pretty powerful for Integration testing.

Could not load type Microsoft.VisualStudio.Services.Common.VssHttpClientBase

If your getting the following error on your TFS server web interface odds are that you are using incompatible version between TFS and VS or other Microsoft product. The object in question was moved from the common Dll to another. In my case I installed TFS RC and then never version of VS2013, after that I got the error.

Could not load type ‘Microsoft.VisualStudio.Services.Common.VssHttpClientBase’ from assembly ‘Microsoft.VisualStudio.Services.Common, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a’.

To remedy the situation I upgraded TFS 2013 with the RTM version. After the upgrade I’m not getting the error anymore ant the TFS web interface works as expected.


I had an idea about writing a small code to animate fireflies. On Christmas break I was bored and I figured I had a few hours to play with it. I also wanted to use some tools I hadn’t used yet and figured that was a good time to do Javascript since I haven’t done much Javascript. I fired up the editor ( Sublime ) and used the browser to run / debug, Firefox and FireBug of course. There is a bit of a difference using this setup compared to writing Java code in Eclipse which I’m used to. First off you don’t get the compilation in Sublime and secondly you have to switch to another program to load and debug. Switching between the two was what annoyed me. Later I though, what if I can find a tool that is an editor and can Ftp to a server as well and runs within the browser. If on each save you can Ftp it to a sever that is serving the Javascript then I could do it all from the browser. I went looking around and fount Net2Ftp which is supposed to at least come close to the tool I’m wishing for. I will have to try it out the next time I’m coding in Javascript. The other thing that got me is that there is no good way of declaring your own classes, you have to work with prototypes and such, why that is beats me.

As you can see from the code, it’s not pretty.

If you want to see the Javascript in action click here.


curl: (60) SSL certificate problem: unable to get local issuer certificate

If you get the following error when using curl for SSL address, here is an easy fix. Your error will probably look something like the following.

curl: (60) SSL certificate problem: unable to get local issuer certificate
More details here:

curl performs SSL certificate verification by default, using a “bundle”
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn’t adequate, you can specify an alternate file
using the –cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you’d like to turn off curl’s verification of the certificate, use
the -k (or –insecure) option.

Just go to it has a list of certification providers. View as source and save it to a file cacert.pem. Then on the curl command just add this in the end pointing to your file –cacert cacert.pem Note you can also try the -k option but that’s cheating 🙂


A better approach is to save the file as curl-ca-bundle.crt and save it in the Windows System directory (e.g. C:\windows\system32)