Wednesday 22 February 2012

Clone local git repository to remote server?

If you have a local repository that you want to clone/copy to a remote server here is how I do it.

Perhaps you have been scaffolding, testing and initial silver bullet development and have realised the project is mature enough to share with others. Or you just want it backed up remotely.

Simple git clone local remote do not work. Destination path for git clone is always local.

What you need to do is on the remote server create a bare git repository:

remoteserver$ mkdir -p /var/local/repos/myproject;
remoteserver$ cd /var/local/repos/myproject;
remoteserver$ git init --bare;


Then add this remote to your local git repository:

localmachine$ git remote add origin \
ssh://remoteserver.example.com/var/local/repos/myproject;


Now every time you want to push to your remote server, you do a normal push:

localmachine$ git push origin master;



Although I would seriously consider using something github or gitorious instead of your own server.



Monday 13 February 2012

Continuous Deployment via Stack Overflow

I do have an interest in Continuous Deployment/Continuous Delivery. Continuous Deployment goes beyond Continuous Integration and automatically deploys builds to production all the time, not once in awhile. It goes well with agile thinking.

With frequent deployments the delta that can go wrong is very small, the feedback is very quick and the knowledge is fresh and active with the developers so fix turnarounds are immediate. By relying heavily on automated integration testing and DevOps that provide automated deployment the result is quick and painless.

This week I answered a difficult question on Stack Overflow. The question by Emwee was for advice on how to use Continuous Deployment with multitude of inter-dependant systems.

It is a tricky question and I did not have an exact answer. My answer was more along the line of how to facilitate an easier deployment by making the dependency and coupling looser and roll-outs smoother.

I referred to Duck Typing, Feature toggles, evolution scripts, version tables, symlink stage & deploy, and referenced a Hacker News discussion on how Amazon deploys their systems, a video on how Netflix builds releases in the cloud and how at IMVU they deploy 50 times a day.

I also referred to Humble and Farley's book on Continuous Delivery.

There was another reply as well by EricMinick referring to his previous answer to a similar question. Eric does in detail describe scenarios of using promotion builds into different isolated test environments and suggest solutions that his company UrbanCode provides in relation with Jenkins.

In the end Continuous Deployment is a great evolution. But with large enterprises you need to keep your tongue straight. But it is worth the investment.


Friday 3 February 2012

Multi book reading

I have a habit that I wonder if others do as well. And I wonder if it is productive or counter intuitive.

What I do is multi-book-reading. By that I mean I read several books at once.

How I do this is by having different books in different locations. And also several books in the same location. I have a preference for printed books. PDFs of books are handy occasionally for specific searches, but I really cannot read page upon page on a screen. Kindle may be nice, but I have not yet jumped on that bandwagon.

This multi-book effect is partially due to laziness, as when I am in the lounge I do not want to have to walk back upstairs to my study if I get a sudden urge to read or fetch a book. So I always have a half read book in the lounge. (Currently in the lounge I am re-reading the Kanban book by Anderson).


In my study I naturally have bookshelves loaded with computers books, especially java, and always a couple on my desk. I tend not to read too long in this room (then why is it called a study?), but a quick few paragraph while the pc is rebooting etc a few times a day. The reference books however might be referred to when needed. (Current study books are Seven Languages in Seven Weeks by Tate and Continuous Delivery by Humble & Farley)

On my bed side table there may be a fiction book. I don't really want to think too much when trying to sleep.

At work I would also have a mini library as I also tend to evangelise and lend books to colleagues. So I usually have a half read book or two or three there as well. Again for quick glances while rebooting etc, but also for longer reads during lunch if I go by myself. (Just finished ReWork by Fried & Heinemeier Hansson and Linchpin by Godin)

When I am out-and-about e.g. queuing for the till in a shop, waiting for the bus or at lunch when I forgot a book, I use the Aldiko e-book reader on my Android phone. Being a sucker for offers at O'Reilly for epub formatted books I have quite a few on my phone. Aldiko is excellent, but the small phone format is in essence rubbish for reading books over time. It is good for quick 1-5 minutes reads but no longer. And useless for reference books as the overview of the page is difficult. (97 Things Every Programmer Should Know by Henney is good for 5 minute reads)

For longer commutes by train or plane I tend to bring an actual book. If I do this regularly I should probably invest in a Kindle. (Read bits of Specification by Example by Adzic on the plane recently)

I tend do a lot of quick reads. As a stop gap filler between other events. Maybe work interrupts, maybe it is some element of ADHD, or probably our 6 months old daughter. This means I constantly waste time remembering the context of where I am in the book.

Longer reading periods is usually a holiday pattern. This would then often involve more fiction books. I read the Night's Dawn trilogy[2][3] over the last few holidays.

Some books I might skim read chapters to get a gist of but I know I can revisit them if I need to know those sections in detail in the future. Some books I never finish. I would say a good third or more in library I have not finished or barely read. Some turned out just not interesting, some are just skim read while others are consequences of multi-book-reading and lower down the reading priority list.

So this multi-book-reading means I do read a lot of books. But it also means I do not finish enough books. Not very "kanban" or "one-piece-flow" :)