Monday, 5 November 2012

Lean book review: Lean Architecture and Lean from the Trenches

Quick review of one of two technical/project management books I read lately.

First is "Lean Architecture" by James Coplien.

Lean Architecture: for Agile Software Development

Coplien is someone I have great respect for, I have listened to a few lectures by him and read several articles. He definitely seems very knowledgeable on the subject and good in panel debates against other self entitled agilistas. Some people may recognise him for his forword in the Clean Code book by Uncle Bob. So I was looking forward to read this book.

However this book was not great. It is very wordy and repetitive. The book keeps going of on a tangent about the history of agile and lean, which while nice is not why I bought the book. Only in the last few chapters does it actually get to the point of the book, the DCI architecture style.

If you want to learn about DCI (Data, Context & Interaction) then it may be the book for you, especially if you want to pick up history of The Toyota Way, Lean and Agile. Otherwise don't bother.

Another book I read is "Lean from the Trenches" by Henrik Kniberg.

Lean from the Trenches: Managing Large-Scale Projects with Kanban

Having previously read two of his other books I was expecting a helpful book. ("Kanban and Scrum - making the most of both" & "Scrum and XP from the Trenches"). Kniberg is very much a Kanban man so I was interested in his Lean views.

And this book I thought was very good. He adopts a reflection of a large scale project for the Police in Sweden, and the aspects they learned by adopting lean practices as they went along. And then in later chapters more detailed reflections and background on subject matters. (I suspect the authoring style leads readers to think it was all accidentally knowledge gained by the team along the way, but knowing his previous experience I am sure he nudged most in the right direction).

His writing style and diagrams are very easy to follow and I finished the book in a few days read on the commute, and was very inspired. Highly recommended.

Wednesday, 23 May 2012

Send email via SendGrid on Heroku using Play! 2.0 with Scala

If you have a Play! framework 2.0 application that you want to send email from, here are a few tips.

These tips assumes you deploy to Heroku, but other platforms should work similarly. The examples here are using Scala, but Java should work along similar lines. Finally the specifics are for the SendGrid add-on for Heroku, but other mail server providers should be fine.

First add the free option of the SendGrid add-on to your Heroku app by typing in:
heroku addons:add sendgrid:starter

Then configure your Play! app to use the mail plugin provided by Typesafe:

Add to your dependencies in the project/Build.scala file: (all on one line)
"com.typesafe" %% "play-plugins-mailer" % "2.0.2"
Then create and add these to a conf/play.plugins file: (all on one line)

Next configure the mail server settings. You can either add these directly to your conf/application.conf file, but I prefer to share my projects' source code, so my production settings are set via environment variables so that my username/password are not publicly available.

However for the plugin to run  must be present. Open conf/application.conf and add:

On Heroku I append the settings to the Heroku's propriatory Procfile file. I append these settings to the Procfile to use SendGrid's servers: (all on one line) -Dsmtp.port=587 -Dsmtp.ssl=yes -Dsmtp.user=$SENDGRID_USERNAME -Dsmtp.password=$SENDGRID_PASSWORD
You may already have other settings in the Procfile, e.g. database URL, so be aware of the 255 char limit, and use a custom properties file instead.
web: target/start -Dhttp.port=${PORT} 

The SendGrid add-on should create the environment SENDGRID_USERNAME and SENDGRID_PASSWORD variables for you.
You can verify this with:
heroku config

Finally we then create our actual application code to send email:
package notifiers
import com.typesafe.plugin._
import play.api.Play.current
import play.api.Play
import play.Logger
object EmailNotifier {
  def sendMail {
    val mail = use[MailerPlugin].email
    mail.setSubject("Mail test")
    mail.addRecipient("Joe Smith  <>","")
    mail.addFrom("Jon Doe <>")
    mail.send( "Test email" )
  def sendTestMail {
    if(Play.current.mode == Mode.Prod){
      Play.current.configuration.getString("") match {
        case None => Logger.debug("Email mock")
        case Some("mock") => 
Logger.debug("Email mock")   
        case _ => sendMail(participant)

  } else {
    Logger.debug("Email mock")}
(In case of this posts cant parse tags replace &lt;  and &gt; with less than and greater than tags;)

This should be all that is needed.

Play! 1.x did have a handy mock email interface for development and testing. I will try and find a suitable replacement for 2.0 and update this post when I do.

For more information

Sunday, 22 April 2012

Play! 1 & 2 command tip

If you love the Play! Framework, you might be like me and have both version 1.x and 2.x installed.

Version 1.x, in my case 1.2.4, is a well established feature rich stable version. 
Version 2.x, in my case 2.0, is a new radically different version, that is still in its infancy but released. 

You might have both installed as you have older projects using 1.x and new in development projects using 2.x, or similar.

With both version the norm is to install them and expose the main executable as "play". So how do you differentiate between which version to use for which project?

OK, it is no rocket science but here is a quick tip on how I do it:

I have Play! 1.x installed in

I have Play! 2.x installed in /usr/local/lib/play-2.0

You can add either play folders to the your PATH, e.g. in /etc/environment: 


But I simple add them to my .bash_aliases file:

alias play1="/usr/local/lib/play1/play"
alias play2="/usr/local/lib/play2/play"

On top of that I symlink this:

$: cd /usr/local/lib;
$: sudo ln -s play-1.2.4 play1;
$: sudo ln -s play-2.0 play2

With this setup I have to make a conscious decision whether to run Play! 1 or 2, and can switch between the two very easily.

$: play1 help;
$: play2 help

Avoiding cyber squatting failure

A year or two ago I misspelled a domain name of very popular site used by many developers. It came up as "Not Found" so I realised as the site at the time was still quite niche (not any more) cyber-squatters had not cottoned on to it yet.

So I registered a couple of similar domain names with a misspelled vowel. This was mainly as I thought it was quite funny at the time, but also I did not want real professional & cynical cyber-squatters to register them either.

Of course I did not know quite what to do with them so I put them as Google parked domains (AdSense for Domains) and forwarded all emails automatically to the proper domain. If ever contacted by the proper site I would just let them have the domain(s).

End of AdSense for Domains

This Spring Google closed their AdSense backed parked domain offering. And I needed to reflect what to do with the domain names and what options I have.

I do not really want to keep paying for their registration, the ads on them brought in less than £20 every year so not likely to challenge my ethical backbone either.

When some of the domain names expired this Spring, and I was initially just going to let them expire, but then from experience I know domain cyber-squatters will be scanning for expired domain names and pick them up. And they will use them far more cynically and unlikely to ever hand them over for proper usage. So I extended my registrations with those domain names.

Domain parking bad taste

In the end I moved the domains from AdSense For Domains to another Domain Parker.

But this has left a really bad taste in my mouth. I am not really any better than a cyber-squatter. I am profiting from misspellings, although less than the registration costs... The content on the parked domains are really of no assistance to the people trying to reach the proper site. So I cannot leave it as it is.

"Nice" Anti Cyber Squatting 

The best solution would be if there was a friendly not-for-profit community back anti-cyber-squatter service. Offering useful content/redirection. A sort of defensive registrations the community can do on behalf of proper sites. Naturally the proper sites should really register these names themselves, but some cant or wont. But to avoid squatters taking advantage a free service like this would be handy. Of course we/I would still have to pick up the registration cost.

Landing page

But instead I think I might put up a brief comical landing page with a big button to go to the proper site. (However until I actually get round to create that, the domains are still listed with the domain parker.... )

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 \

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" :)

Tuesday, 17 January 2012

SOPA protest page and 503 redirect

Tomorrow, 18t January 2012, many websites will protest against the US SOPA and PIPA acts. For example Wikipedia will go blank in protest for 24 hours.

For those intending to blackout their own websites (or in the future intend to do something similar, e.g. a more practical "web site temporarily down message" while doing an upgrade etc, here are a few tips:

First of all Google recommend you do not simple just change your website front page to a blank page or similar. As this can have repercussions on your SEO, ie your search ranking. Read more about it in this post on Google+ by a Googler. They recommend a 503 error response instead. Which indicates the site is temporarily down.

So a simple change of index.html is not recommended. Nor is a simple redirect in the html's meta header, nor a plain http 302 redirect. All this can affect your ranking.

I recommend (if using Apache 2) to use mod_rewrite in this manner:

RewriteEngine on
RewriteCond %{ENV:REDIRECT_STATUS} !=503
Alias /stop-sopa /var/www/stop-sopa
ErrorDocument 503 /stop-sopa/index.html
RewriteRule !^s/stop-sopa$ /stop-sopa [L,R=503]

This uses Alias to another folder so that the same message can be used for several virtual hosts. It uses a custom ErrorDocument to display a human readable blackout page. And it uses RewriteRule to redirect all requests to the stop-sopa page (except for request for /stop-sopa so that you don't get an infinite loop).

If you are looking for a page to use as the blackout page, there is a nice github project page for just that. An example can be viewed here.

Saturday, 14 January 2012

Agile project tools for personal/open source projects

Been briefly assessing some online free tools for agile task planning for a few personal FOSS projects.

A physical task board is perhaps the suggestion from the agile purists, however not useful for me (nor my family :)).

At work I often have to use the awful Quality Center. It is good for planning functional testing, but not much else. The user interface is painful, and only works on windows with IE.

But most project I have been on eventually drop it for the more developer friendly Jira by Atlassian. Its UI gets cleaner and cleaner. And is great for Scrum projects since the intergration of GreenHopper. It is however very feature rich which is good and bad, and sometimes quite slow. I recommend Jira for distributed larger organisations. It is however an overkill for my needs.

I have been using Pivotal Tracker for some of my projects for a few years. It is a great tool. For scrum projects it is the tool I would recommend the most. They recently started charging but it is still free for public projects. It is however very iteration/scrum centric and as such not useful for my more Kanbanish time irrelevant requirements.

So I started to look at more tools (and revisit some previous ones).
My requirements are:

  1. Free, as in beer or near enough. $9/month and similar is too much for personal projects unless heavily used.

  2. Agile task board simulation

  3. Not time iteration based

  4. Simple functional UI, but not ugly

  5. Icebox feature for storing tasks/ideas not yet ready for the backlog

  6. Pivotal like Feature, Chore and Bug classification

  7. Limiting WIP

  8. Kanban queues

  9. Simple T-shirt or fibonacci estimates

Not all requirements have to be met.

Here are my initial impressions:

Pivotal Tracker

Time iterative centric.
Looks nice. Clean interface.
No WIP limit.
No kanban queue.
Got Icebox feature
Got Feature-chore-bug classification.
Fibonacci estimates.
Unlimited free public projects.


Kanban style flow.
Looks nice. Clean interface.
Columns can be renamed.
Got WIP limit.
No icebox. Can rename backlog icebox and rename another column backlog.
No estimates
Only 1 project on the free price plan.
FOSS projects can apply for free usage.


Kanban style flow.
Looks nice. Clean interface.
Columns can be renamed.
Got WIP limit.
Got Icebox feature
Got Feature-chore-bug classification.
T-shirt estimates.
Only 1 project on the free price plan.
No FOSS free plan.


Kanban style flow.
Clean interface.
Little confusing UI.
Got Kanban queues.
Got WIP limit.
Got Icebox (the "backlog").
No estimates.
Unlimited projects.
All plans are free.
Permissions are strange. No member can edit and public can only view. Either member view and edit with no public access, or public(anonymous) can view and edit!!


Kanban style flow.
Seems very feature rich. Perhaps too many features.
UI a little cluttered.
Tasks seems too much like post-it notes.
Only 1 project on the free price plan.
No FOSS free plan.


Scrum focused.
Looks nice.
Feature rich.
UI a little confusing.
No Icebox.
No WIP limit.
No kanban queue.
Fibonacci and t-shirt estimates.
10 project on the free price plan.
No FOSS free plan.


Kanban style flow.
Tasks seems too much like post-it notes.
No Icebox.
Got WIP limit.
Only 1 project on the free price plan.
FOSS projects can apply for free usage.

I may update this in the future when I get more impressions of the ones I use and if I find other tools.

My recommendations depends, but currently they are:

  • For large commercial projects Jira offer features and reports. And can be installed inside your firewall.

  • For Scrum projects Pivotal Tracker offers the most complete package.

  • For Kanban projects, the it depends on your own requirements and taste, but my current favourites are Kanbanery and AgileZen. Kanbanpad's no restrictions on number of projects is also tempting

Wednesday, 11 January 2012

Play! 2.0 in IntelliJ IDEA

Play! Framework 1.x supported creating an IntelliJ IDEA project by the command: play idealize.

However while Play! Framework 2.0 is in beta that command does not work**.

So how do you get your Play! 2.0 project to open in IntelliJ IDEA? There are few different work arounds. Especially regarding integrating sbt.

However I have a quick way. For this to work you need both Play! 2.0 and Play! 1.2.x installed.

Create Play! 2.0 project:
/usr/local/lib/play-2.0-beta/play new helloworld
(I am assuming it was a Java project that you chose)

Rename project folder:
mv helloworld helloworld2

Create Play! 1.x project:
/usr/local/lib/play-1.2.4/play new helloworld

Create IntelliJ project:
cd helloworld;
/usr/local/lib/play-1.2.4/play idealize

Move IntelliJ files to Play! 2.0 project:
cd ..;
mv helloworld/helloworld.i* helloworld2/

Remove 1.x project and rename 2.0 folder:
rm -rf helloworld;
mv helloworld2 helloworld

Now you can open IntelliJ and then go to file/open project, then find and open helloworld/helloworld.ipr.

There will be some issues such as libraries etc but this a good start. For further tips try these suggestions.

** As of 11th of January 2012 it is not present in Play! 2.0. I fully expect Play! to create an idealize, eclipsify, netbeansify etc as soon as 2.0 is stable.