#21 Add Zipkin optional module

[arey]

Sometimes, the export flag in the Sleuth logging has changed from false to true even if I use the AlwaysSampler:

2016-12-01 17:20:22.274  INFO [customers-service,b3c13ce8162f4c28,4c6423b12bee47f1,true] 16810 --- [o-auto-1-exec-6] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@55c824f id = 1, new = false, lastName = 'Franklin', firstName = 'George', address = '110 W. Liberty St.', city = 'Madison', telephone = '6085551023']
2016-12-01 17:20:37.401  INFO [customers-service,27928a1296dfe5dd,18b41529de8b6396,false] 16810 --- [-auto-1-exec-10] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@41e91d81 id = 2, new = false, lastName = 'Davis', firstName = 'Betty', address = '638 Cardinal Ave.', city = 'Sun Prairie', telephone = '6085551749']
2016-12-01 17:20:40.660  INFO [customers-service,a0da1ec02a5d0e54,e69793c518f85ec9,true] 16810 --- [o-auto-1-exec-4] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@29c13699 id = 5, new = false, lastName = 'McTavish', firstName = 'Peter', address = '2387 S. Fair Way', city = 'Madison', telephone = '6085552765']
2016-12-01 17:23:13.616  INFO [customers-service,e6312fbff4020889,89776f2ba1fdfdb9,false] 16810 --- [-auto-1-exec-10] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@7fe6f968 id = 1, new = false, lastName = 'Franklin', firstName = 'George', address = '110 W. Liberty St.', city = 'Madison', telephone = '6085551023']
2016-12-01 17:23:39.336  INFO [customers-service,e59bc823df24d0ba,847b62aba993eeb,false] 16810 --- [o-auto-1-exec-4] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@7d806d4b id = 1, new = false, lastName = 'Franklin', firstName = 'George', address = '110 W. Liberty St.', city = 'Madison', telephone = '6085551023']

@mszarlinski could you please test this change?

[mszarlinski]

Will check it tomorrow

[mszarlinski]

I think we are missing a sampler configuration. There are two possibilities:

• register AlwaysSampler bean,
• add spring.sleuth.sampler.percentage=1.0 property.

Source: Blog post, Sample on GitHub

[arey]

I've done some local test with AlwaysSampler but I don't commit it.
In the Spring Cloud Steuth documentation http://cloud.spring.io/spring-cloud-static/spring-cloud-sleuth/1.1.0.RELEASE, we could read :

the PercentageBasedSampler is the default if you are using spring-cloud-sleuth-zipkin or spring-cloud-sleuth-stream. You can configure the exports using spring.sleuth.sampler.percentage. The passed value needs to be a double from 0.0 to 1.0 so it’s not a percentage. For backwards compatibility reasons we’re not changing the property name.

To avoid adding AlwaysSampler in each web app, in the application.yml of the spring-petclinic-microservices-config we could add

spring:
  application:
  sleuth:
    sampler:
      percentage: 1.0

[mszarlinski]

According to documentation it must be a double property (1.0). Please add it to config repo as you described, so we don't need any changes in code.

[arey]

I've pushed the change and all traces are now sent to Zipkin:

2016-12-02 16:43:36.124  INFO [customers-service,edc5a9146f915a6,51f537b601fc003d,true] 32988 --- [o-auto-1-exec-8] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@b321cda id = 3, new = false, lastName = 'Rodriquez', firstName = 'Eduardo', address = '2693 Commerce St.', city = 'McFarland', telephone = '6085558763']
2016-12-02 16:43:52.270  INFO [customers-service,9682875e7a558dc0,e0b1fa108997b78a,true] 32988 --- [o-auto-1-exec-2] o.s.s.p.c.application.OwnerService       : Saving owner [Owner@635baaf2 id = 4, new = false, lastName = 'Davis', firstName = 'Harold', address = '563 Friendly St.', city = 'Windsor', telephone = '6085553198']
2016-12-02 16:44:00.599  INFO [customers-service,b5c83f278052b157,c7693268f397f0cf,true] 32988 --- [-auto-1-exec-10] o.s.s.p.c.application.PetService         : Saving pet Basil