updates to localhost tunnels and powershell pages

mattmakai · mattmakai · commit 007e20310a0e · 2018-05-06T09:02:16.000-04:00
diff --git a/content/pages/02-development-environments/10-powershell.markdown b/content/pages/02-development-environments/10-powershell.markdown
@@ -20,7 +20,11 @@ of a Python programmer's
 
 ### PowerShell resources
 * [A Python Developer's Guide to Powershell](https://akr.am/blog/posts/a-python-developers-guide-to-powershell)
+  explains the PowerShell scripting language then shows how to combine a
+  Python script and a PowerShell script to automate web scrapining downloads.
 
 * [ChatOps with PowerShell](https://www.youtube.com/watch?v=XIMOFnfdOx0)
 
+* [PowerShell in Azure Functions](http://www.brianbunke.com/blog/2018/02/27/powershell-in-azure-functions/)
+
 * [Getting Started with Windows PowerShell](https://docs.microsoft.com/en-us/powershell/scripting/getting-started/getting-started-with-windows-powershell)
diff --git a/content/pages/02-development-environments/18-environment-variables.markdown b/content/pages/02-development-environments/18-environment-variables.markdown
@@ -18,3 +18,10 @@ by Python applications to affect a program's execution.
 * [Why you shouldn't use ENV variables for secret data](https://diogomonica.com/2017/03/27/why-you-shouldnt-use-env-variables-for-secret-data/)
 
 * [Environment variables in Windows](https://www.digitalcitizen.life/simple-questions-what-are-environment-variables)
+
+* One answer I found very useful when learning about getting environment
+  variables in Python code is 
+  [knowing the difference between os.getenv and os.environ.get](https://stackoverflow.com/questions/16924471/difference-between-os-getenv-and-os-environ-get).
+  Either one can be used in your applications but there are slight
+  differences that can make one better than the other in various
+  situations.
diff --git a/content/pages/02-development-environments/19-localhost-tunnels.markdown b/content/pages/02-development-environments/19-localhost-tunnels.markdown
@@ -8,13 +8,26 @@ meta: Localhost tunnels allow anyone with a tunneling URL to connect to a server
 
 
 # Localhost tunnels
-Localhost tunnels allow anyone with a tunneling URL to connect 
-to a server running on your local development system.
+A localhost tunnel establishes a connection between your local machine
+and a remote connection. The connection is intended to proxy traffic 
+from a publicly-addressable IP address and URL to your local machine.
+Localhost tunnels are most useful for allowing a tester to connect 
+to a server running on your local development system so they can try
+out an in-development application you are building but have not yet
+[deployed](/deployment.html).
 
 
 ### Localhost tunnel services
-* [ngrok](https://ngrok.com/)
+There are numerous localhost tunnel services that have similar features.
+The following services are listed in order from ones I have had the most 
+experience with to the ones I have not used.
 
-* [Localtunnel](https://localtunnel.github.io/www/)
+* [ngrok](https://ngrok.com/) is the service I use most often. It is
+  easy and worth the small fee to upgrade your account with a few
+  extra features such as fixed, customizable subdomains.
 
-* [Burrow](https://burrow.io/)
+* [Localtunnel](https://localtunnel.github.io/www/) is a localhost
+  tunnel written in Node.js.
+
+* [Burrow](https://burrow.io/) provides another service, albeit one
+  that I have not used myself.
