Google App Engine deploy error: Error when loading application configuration:Unable to assign value ‘1.9.31’ to attribute ‘version’:Value ‘1.9.31’ for version does not match expression ‘^(?:^(?!-)[a-z\d\-]{0,62}[a-z\d]$)$’

This is a bug in app engine maven plugin. In your pom.xml, rename appengine.version to appengine.sdk.version. More on that here:


IntelliJ and Maven- Auto deploy static files

Doing a deploy just to refresh the static files is a time consuming process, which is usually the case if you have a maven WAR project running from IntelliJ. Every time you update a static file like ‘.js’ or ‘.css’ file, you have to do a deploy for the changes to reflect in browser. A quick work around would be to ‘Make’ the project (Ctrl+F9 in Windows) and enable the ‘build on make’ checkbox for ‘exploded war artifact’ in project structure settings.

Google App Engine – Eclipse plugin issues

When you start with a maven project and import that into Eclipse, you might run into issues while importing. You might get An internal error occurred during: “Updating Maven Project”. java.lang.NullPointerException right after you do a maven import. If that is the issue, make sure you have installed the “appengine m2e plugin” and the App Engine SDK. Then delete your .metadata directory and .project file. And redo the import. This time it should take more than a minute as Maven starts downloading all the required dependencies.

Then you should be able to import the project without errors and run the project by right clicking and selecting ‘run on server’ -> ‘Google App Engine’. If the project didn’t import correctly, you might get Error: Could not find or load main class error. More on that here. Just repeat the above steps to fix the error.

Git Error: ECMDERR Failed to execute “git ls-remote –tags –heads git://”, exit code of #128 fatal: unable to connect to[0:]: errno=Connection refused

Do the following and try again:

git config --global url."https://".insteadOf git://


Simple server using node.js

Simplest Node.js server is just:

$ npm install http-server -g
Now you can run a server via the following commands:

$ cd MyApp

$ http-server

For more, see

Disable services in OSX Mac using launchctl

Run this in terminal:

sudo launchctl unload -w


sudo launchctl unload -w*

for disabling all the services that start with

VirtualBox Guest Additions

I had a hard time installing these in Lubuntu since it was failing due to not able to find ‘gcc and make’ utils. It is easier to install it from apt repo using:
sudo apt-get install virtualbox-guest-dkms

CSS vertical centering using display: table and display: table-cell.

Sometime the div with display: table doesn’t stretch to the full height of the containing div. It is probably because the position for that div was set as position: absolute. To overcome this limitation, wrap that div with an outer div with position: absolute and make this div’s position: static. That will stretch display: table div element of the height of the parent div.

More on that here:

Running Mac OS X in fullscreen in virtualbox

There are several options to do that, just Bing. But only one did the trick for me. Here it is. During the boot, hit enter and enter the following boot option:
“Graphics Mode”=”1600x900x32”
1600×900 is the resolution of my Dell laptop screen (Host machine). You can find more boot options here:

AEM clear clientlibs cache

Visit this url on Author instance:

If clearing cache or rebuild doesn’t fix the issue with clientlibs not rendering correctly, restarting the publish instance should take care of it.