Tag Archives: guide

Update Wireless Info on Raspberry Pi

Hi everyone,

Just a quick post on how to configure wireless info on a raspberry pi. To start with, open the config file:

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

You can then add any number of connections to the file with varying priorities:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev

        ssid="Mobile Network"

        ssid="Home Network"

Then save the file. Your raspberry pi will now connect to the network with the highest priority first (home network), when that’s not available it will use the network with the lower priority (mobile network).

The official doco is actually pretty good for this use case if you need more info: https://www.raspberrypi.org/documentation/configuration/wireless/wireless-cli.md

Parsing Hash Args for Cognito Auth – Javascript

Hi everyone,

A quick post on a function for parsing hash args when using AWS Congito.


Just in case the fiddle ever disappears:

const parseHashArgs = aURL => {

  aURL = aURL || window.location.href;

  var vars = {};
  var hashes = aURL.slice(aURL.indexOf('#') + 1).split('&');

  for (var i = 0; i  1) {
      vars[hash[0]] = hash[1];
    } else {
      vars[hash[0]] = null;

  return vars;


Thanks to this link on Github: https://gist.github.com/miohtama/1570295/289d5a82e65663c9b515c88186a268c6dd1fddb7

AWS Installing AWS Inspector Agent on Windows EC2 Instance

Hi everyone,

Just a quick post on installing the AWS Inspector Agent on a Windows EC2 instance.

Open PowerShell and run the following command:

(new-object System.Net.WebClient).DownloadFile('https://inspector-agent.amazonaws.com/windows/installer/latest/AWSAgentInstall.exe','C:UsersAdministratorDesktopAWSAgentInstall.exe')

On your desktop, right click on AWSAgentInstall.exe and select run as administrator. Follow the prompts.

Go to run, and execute services.msc. You should now see the Amazon SSM Agent:

If you go to your amazon console > amazon inspector > assessment targets > Click on your relevant target > Preview Target:

Your agent status should now be healthy.

Thanks to these links for the info:

Dynamic Robots.txt with Web Api 2

Hi everyone,

For a project I’m currently working on I needed a dynamic robots.txt. Because our test environment is public facing we want to keep it from being indexed by Google etc. It took a bit of Googling to find a solution that worked, but in the end it was actually pretty simple.

Here’s the action in one of the API Controllers:

    public class UtilitiesController : CustomBaseApiController
        public HttpResponseMessage GetRobotsFile()
            var resp = new HttpResponseMessage(HttpStatusCode.OK);
            var stringBuilder = new StringBuilder();

            if (Helpers.IsProduction())
                // Allow bots in production
                stringBuilder.AppendLine("user-agent: *");
                stringBuilder.AppendLine("disallow: ");
                // Don't allow bots in non-production environments
                stringBuilder.AppendLine("user-agent: *");
                stringBuilder.AppendLine("disallow: *");

            resp.Content = new StringContent(stringBuilder.ToString());

            return resp;

Also need to add the following to your web.config so that the robots.txt file can processed by the routing handler. Without this IIS will attempt to serve it as a static file and will return a 404 when it’s not found:


In production you’ll end up with the following:

user-agent: *

And any other environments:

user-agent: *
disallow: *

Thanks to these answers on stackoverflow for the info:

Including an Externally Hosted Script in ReactJs

Hi everyone,

Just a quick example of how to include an externally hosted js file in a reactjs app. In index.html add your script tag as you would in a normal app:


Then in the file you plan to use the library you can add a const and reference it normally:

const promisepay = window.promisepay;

Thanks to this link for the info: https://stackoverflow.com/a/44877953/522859

Allow Number and String for PropTypes – ReactJS

Hi everyone,

A quick post on how to allow a string or number when defining PropTypes:

static propTypes = {
        numberField: PropTypes.number.isRequired,
        stringField: PropTypes.number.isRequired,
        mixedField: PropTypes.oneOfType([PropTypes.string, PropTypes.number]).isRequired

Thanks to this stackoverflow post for the info: https://stackoverflow.com/a/41808543/522859