• Bernd Zuther
  • @Bernd_Z
  • github.com/zutherb
  • bernd.zuther@codecentric.de

public class TopSellerRecommendationPanel extends AbstractShopBasePanel {

    @SpringBean
    private FeatureToogleBean featureToogleBean;

    ...

    @Override
    protected void onConfigure() {
      super.onConfigure();
      setVisible(featureToogleBean.isTopSellerFeatureEnabled());
    }

    ...

}

• Reduction of development speed
• Increase of turnaround times
• Increase of build time
• Strange behavior after changes
• Increase of time to market
• A/B testing of process changes nearly impossible
• Scalability (e.g. application and teams)

vagrant@app-server-node-4:~$ ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1  0.0  0.2  29640  4300 ?        Ss   08:38   0:02 /sbin/init
root         2  0.0  0.0      0     0 ?        S    08:38   0:00 [kthreadd]
root         3  0.0  0.0      0     0 ?        S    08:38   0:02 [ksoftirqd/0]
root         5  0.0  0.0      0     0 ?        S<   08:38   0:00 [kworker/0:0H]
...
vagrant@app-server-node-4:~$ ps aux | grep java
root      1827  1.4  7.2 2458576 149452 ?      Sl   08:39   8:26 java -classpath
/usr/share/shop/product/lib/product-microservice-0.5.5.jar:/usr/share/shop/produ
ct/lib/scala-library-2.10.3.jar:/usr/share/shop/product/lib/akka-actor_2.10-2.2.
4.jar:/usr/share/shop/product/lib/spray-can-1.2.1.jar:/usr/share/shop/product/li
...
vagrant@app-server-node-4:~$ ps aux | grep java | wc -l
6

{
        firstname: "Bernd",
        lastname: "Zuther",
        street: "Elsenheimerstraße 55a",
        city: "München",
        zip: 80687
}

{
        firstname: "Bernd",
        lastname: "Zuther",
        birthday: "1983/08/15",
        street: "Elsenheimerstraße 55a",
        city: "München",
        zip: 80687
}

{
        firstname: "Bernd",
        lastname: "Zuther",
        birthday: "1983/08/15",
        addresses : [{
          street: "Elsenheimerstraße 55a",
          city: "München",
          zip: 80687,
          type: "WORK"
        }]
}

• Don’t break your Customer
• Don’t break the Code Base, Builds, Tests, and Production
• Don’t break the Delivery Flow

{
        firstname: "Bernd",
        lastname: "Zuther",
        birthday: "1983/08/15",
        street: "Elsenheimerstraße 55a",
        city: "München",
        zip: 80687,
        addresses : [{
          street: "Elsenheimerstraße 55a",
          city: "München",
          zip: 80687,
          type: "WORK"
        }]
}

• URL:
  • simply whack the API version into the URL, e.g. https://shop/api/v2/cart/all
• Custom request header:
  • same URL as before but add a header “api-version: 2”
• Accept header:
  • modify accept header to specify the version, e.g. “Accept: application/vnd.cart.v2+json”

www-data  1699  0.5  7.7 2453320 158076 ?      Sl   10:49   0:26 java -cp cart.jar
www-data  1834  0.3  5.0 2435400 102684 ?      Sl   10:49   0:17 java -cp navigation.jar
www-data  1972  0.0  0.1  90792  3124 ?        Ss   10:49   0:00 nginx: master process
www-data  1973  0.0  0.1  91148  3820 ?        S    10:49   0:00 nginx: worker process
www-data  1974  0.0  0.1  91148  3820 ?        S    10:49   0:00 nginx: worker process
www-data  1975  0.0  0.1  91148  3820 ?        S    10:49   0:00 nginx: worker process
www-data  1976  0.0  0.1  91148  3820 ?        S    10:49   0:00 nginx: worker process
www-data  1980  1.5  7.0 2456532 143688 ?      Sl   10:49   1:20 java -cpa product.jar

redis:
  image: dockerfile/redis
  ports:
    - "6379:6379"
cart:
  image: eshop/cart-service
  ports:
    - "18100:18100"
  links:
    - redis
catalog:
  image: eshop/catalog-frontend
  ports:
    - "80:80"
  links:
    - product
    - cart