Can't connect to localhost:8080 when trying to run Google App Engine program
I had the same problem. This seemed to fix it:
cd to google_appengine, run
python dev_appserver.py --port=8080 --host=127.0.0.1 /path/to/application
at this point there is a prompt to allow updates on running, I said Yes.
At this point the app was running as it should, also when I quit this and went in using the launcher again, that worked too.
I'm trying to run the Google App Engine Python 2.7 Hello World program and view it in a browser via Google App Engine Launcher. I followed the install and program instructions to the letter. I copied and pasted the code in the instructions to the helloworld.py file and app.yam1 and verified that they are correct and in the directory listed as the application directory. I hit run on the launcher and it runs with no errors, although I get no sign that is has completed (orange clock symbol next to app name). I get the following from the logs:

Running dev_appserver with the following flags: --skip_sdk_update_check=yes --port=8080 --admin_port=8000 Python command: /opt/local/bin/python2.7

When I try to open in the browser via the GAE Launcher, the 'browse' icon is grayed out and the browser won't open. I tried opening localhost:8080 in Firefox and Chrome as the tutorial suggests, but I get unable to connect errors from both.
How can I view Hello World in a browser? Is there some configuration I need to make on my machine?