In this tutorial you will learn the basics about Microservices with Java using the MSF4J, which is a very lightweight and rich framework.

1. msf4j –
Microservices Framework for Java
Workshop
Edgar Silva
edgar @wso2.com

2. o This workshop is intend to cover how to use the WSO2
Microservices Server for Java – msf4j, we will cover
some basic overview about some concepts, but we
strongly recommend you look for more detailed basics
about Microservices.
o Recommended reading:
o http://nginx.com/blog/introduction-to-microservices/
o https://www.nginx.com/blog/building-microservices-using-an-api-
gateway/
2

3. 3

4. 4
Basics Pre-Reqs

5. o Java 8
o Maven
o See the MSF4J releases page:
o https://github.com/wso2/msf4j
o Let’s work direct from the source:
o Git pull
o https://github.com/wso2/msf4j
o Or simply download from this url: (easier)
https://github.com/wso2/msf4j/archive/master.zip
5

7. 7

8. 8

9. o So, cd
<msf4j_HOME>/samples
o Make you sure you could
import the project
hello_world
9

10. o Go to the dir:
o <msf4j_HOME>/samples/hello_world
o Type:
mvn package
10

11. o After Maven process
o ( be pacient with downloading  )
o What is happening:
o The pom.xml inside the sample, inherits the dependencies
from the root’s pom.xml, that’s why you don’t need to worry
with this process
o In a few (seconds) you will have a hello_service....jar into
your target folder.
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12. 12
• Msf4j is booting in my case in about less than 300ms
• In the previous maven process, every dependency from other jars were
included into your helloworld-1.0.0-SNAPSHOT.jar, including the reference
to the Main Java Class.
• Everything you need is ready 

13. 13
package org.wso2.carbon.msf4j.example;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
/**
* Hello service resource class.
*/
@Path("/hello")
public class HelloService {
@GET
@Path("/{name}")
public String hello(@PathParam("name") String name) {
return "Hello " + name;
}
}
}
JAX-RS
Simple class (REST Endpoint
REST Java Method

14. o The simplest Java Class startup
o See the main method:
14
public class Application {
public static void main(String[] args) {
new MicroservicesRunner()
.deploy(new HelloService())
.start();
}

15. 15
edgar$ curl -v http://localhost:8080/hello/valentina

16. o Take a look on this:
o http://www.confusedbycode.com/curl/
16

17. o Thanks @jpviragine for that great tip:
https://github.com/jkbrzt/httpie
o Really great tool, works like cURL, but much better and more user friendly
o Syntax: http <options> service or URL
o But if you prefer to be “roots”, ok, continue if cURL
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public class Application {
public static void main(String[] args) {
new MicroservicesRunner(7888, 8888)
.deploy(new HelloService())
.start();
}
Services exposed through different ports(*)
(*) Default port is 8080 when no ports are specified

19. 19

20. 1. Enter in the
<msf4j_home>/samples/stockquote-service
2. mvn package
3. java -jar target/stockquote-service-1.0.0-
SNAPSHOT.jar
20

21. o In the console type: (Windows Users
o curl -v http://localhost:8080/stockquote/GOOG
21

22. o Now we will send a POST message to our Service:
o Please type (or copy and paste) the following command:
o curl -v -X POST -H "Content-Type:application/json" -d
'{"symbol":"BVMF","name":
"Bovespa","last":149.62,"low":150.78,"high":149.18,"createdByHost":"localh
ost"}' http://localhost:8080/stockquote
o This command will save a new Symbol into our Stock Quote Service
22

23. o You had used:
o Java 8 + maven for building our samples and
exercises
o Executed Microservices with basic jar –jar approach
o You saw how easy you can build REST Services
using Microservices approach
23

24. 24

25. o Several approaches for a “decoupled SOA”
o In this tutorial we will use the “Container-based
approach”
o Microservices are about:
o Lighter
o Business Need Oriented
o Composable
25

26. 26
Web
Server
ASP.NET ADO.NET
Windows OS
.NET CLR RuntimeFront-Store
HTML

27. 27
Web
Server
Web
Framework
(JSF,
Struts, etc)
Persitence
(JPA,
Hibernate,Sprin
gTemplates)
Any OS
JVM
Other
(JMS, JTA
etc)
App Server
Front-Store
HTML

28. 28
Product Service
get /products
post /products
get /products/{id}
get /products/offset/10/1
CustomerService
get /customers
post /customers
get /customers/{id}
get /customers/export
AddressService
get /address
post /address/{zip}
get /address/geo/{x}/{y}
3Examples

29. 29
Product Service
CustomerService
AddressService
AddressService ProductService
Customer
Service
AddressService Customer Service
SinglePage APP
HTML
FrontStoreService
Delivery Service

30. o Quick deployments
o You are deploying a loosely-coupled, modular
component only 
o Not a huge EAR with dozens of Jars as you used to do in a
monolithic enterprise App
30

31. 31
Monolithic
Microservices
Reference: http://martinfowler.com/articles/microservices.html#ComponentizationViaServices

32. 32
Paulo Merson https://insights.sei.cmu.edu/saturn/2015/11/defining-microservices.html
Great definition, written by another Brazilian 
From an architecture perspective, the microservice style belongs primarily to
the deployment view.
It dictates that the deployment unit should contain only one service or
just a few cohesive services.
The deployment constraint is the distinguishing factor. As a result,
microservices are easier to deploy, become more scalable, and can be
developed more independently by different teams using different
technologies.
“

33. o Benefits of using microservices:
o Deployability
o Availability
o Scalability
o Modifiability
o Management
33
Paulo Merson https://insights.sei.cmu.edu/saturn/2015/11/microservices-beyond-the-hype-what-you-gain-and-what-you-lose.html
( Great post )

34. o I would add:
o Deployability
o Availability (Auto-Scaling via Containers)
o Analytics
o Scalability
o Modifiability
o Management
34
Paulo Merson https://insights.sei.cmu.edu/saturn/2015/11/microservices-beyond-the-hype-what-you-gain-and-what-you-lose.html

35. 35

36. o Part 2:
We ship in the distro
an example showing how to
run a whole deploy from several
different container machines managed
by Kubernetes.
36

37. o In your command line, go to your:
<msf4j_home>/samples/petstore
o Enter in deployment folder and execute: run.sh
o That’s all, time to get some juice, it will download everything you need:
o Vagrant
o CoreOS
o Kubernetes
o Docker
37

38. o https://github.com/wso2/product-
msf4j/tree/master/samples/petstore/deployment/kubernet
es-vagrant-coreos-cluster
o Disclaimer: This tutorial is focused on WSO2 Micro
Services Server – msf4j, and some introduction to the
basics on Kubernetes is strongly recommended before
you move forward on this tutorial.
38

39. 39
This step will get a few minutes, according to your internet and machine,
So get relaxed while you can enjoy some “Matrix-like” in your console
http://thenextweb.com/wp-content/blogs.dir/1/files/2013/11/relax-at-work.jpg

40.  Double check if your JAVA_HOME is Java 8
 Please , if you are using MacOS, make sure you that you have wget
installed.
 Recommend you use brew install wget
 If you get errors communicating with Kubernetes nodes, please add this
variable before execute run.sh:
 export KUBERNETES_MASTER=http://172.17.8.101:8080
 That will be the default Kubernetes UI Console and API Address
40

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Our traditional Pet Store Sample
has the following Microservices …
fileserver frontend-admin frontend-user
Pet (store) transactionsecurity

42. o If you are using VirtualBox as the Hypervisor
(recommended), you will see the following 3
VMs started
42

43. o Please, execute the command:
o kubectl get pods
o The result must be like this:
43
All the pods, must be
Like this, keep repeating
This process until all get
ready

44. o Please, execute the command:
o kubectl get pods
o The result must be like this:
44
Troubleshooting:
If your pet-xxx appears
the READY info as 0/1
It might be not initialized
Syncronized with Redis.
To solve that, execute:
./clean.sh and later on
./petstore.sh

45. o Kubernetes UI
o Nodes
o Services
o Pods
o General Info
o Pet Store Admin (PHP App)
o Pet Store Site (PHP App)
45

46. http://172.17.8.101:8080/ui
Here is the Kubernetes Admin that you can open in your browser
46

47. Relationship between the VMs and Kubernetes (Nodes)
47
Here you can see the Ips
Attached to the each Node

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Viewing the Pods
http://kubernetes.io/v1.0/docs/user-guide/pods.html

49. 49
Viewing the Pods
http://kubernetes.io/v1.0/docs/user-guide/pods.html

50. 50
Viewing the Services

51. 51
Viewing Replication Controllers
In Kubernetes, the base unit of deployment is a pod (intro to pods), which is a
group of containers that work together and therefore are logically grouped. The
replication controller stores a pod template in order to create new pods if
needed.
https://coreos.com/kubernetes/docs/latest/replication-controller.html

52. 52
Your Machine OS
Hypervisor
Kubernetes Cluster-Master
K8S Node 01 K8S Node 02
Pods Pods
Replication Controller
Service

53. 53
Your Machine OS
Hypervisor
Kubernetes Cluster-Master
K8S Node 01 K8S Node 02
Pods Pods
Replication Controller
Service
Browser

54. 54
Your Machine OS
Hypervisor
Kubernetes Cluster-Master
K8S Node 01 K8S Node 02
Pods Pods
Replication Controller
Service
Browser
NGINX

55. 55
Getting Actual pods:
$ kubectl get pods

56. 56
Getting details about some pod, for instance
$ kubectl describe pods store-fe-r43hm

57. 57
Getting details about some pod, for instance
$ kubectl describe pods store-fe-r43hm
Please, note here which is the
Pod internal IP: 10.244.36.23
And in which Node this pod
Is actually running
Important: notice that the pod’s id
will change if you restart your
environment 
In my actual case, my pod is
store-fe-<id>, id= r43m

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Getting Actual Services:
$ kubectl describe service store-fe

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Persistence Repository / Services
"Containerized” Microservices based in pure java –jar approach
Client Apps (PHP)
petstore-admin petstore

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You will need to browse the service: admin-fe
http:// Node Server IP: Node Port
Ex: http://172.17.8.102:30984/

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admin/admin

64. fileserver

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You will need to browse the service: store-fe
http:// Node Server IP: Node Port
Ex: http://172.17.8.102:31466/

67. Here the Microservices Transaction
Is invoked.

68. o Executing the petstore sample
o Understanding the basics from Kubernetes and
its concepts, such as pods, services and
Replication Controller.
o Executing the Services and Apps

69. o Proposed Lab:
o Execute the previous samples from Part1 in
Kubernetes + Docker
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70. 70

71. o Please go to : http://wso2.com/products/data-analytics-server/
o Download the product
o Install the product:
1. Unzip
2. That’s all
3. Let’s call your installation destination folder as DAS_HOME from now
on
o MySQL for this sample is also required
71

72. o Step 1: Configure WSO2 DAS
1. Go to <msf4j_HOME>/analytics/das-setup and execute setup.sh :
1. /setup.sh -d <DAS_HOME> -u admin -p
2. Done, everything will be done by the script!
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73. o Step 2: Execute DAS Server
1. Enter in DAS_HOME
2. Make sure that Java 8 is in the path
3. Type sh bin/wso2server.sh
4. Wait until to see a message in the console like this:
5. Open this browser URL, it will let you see the WSO2
Data Analytics Server Console (default user admin
and password admin)
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74. 74
WSO2 DAS is ready and configured!

75. o Step 3: (based on
https://github.com/wso2/product-
msf4j/tree/master/samples/metrics)
1. Go to <msf4j_HOME>/samples/metrics
2. Execute mvn clean install
3. Please, export the following system variables:
1. export METRICS_REPORTING_DAS_DATAAGENTCONFIGPATH="data-agent-conf.xml”
2. export HTTP_MONITORING_DAS_DATAAGENTCONFIGPATH="data-agent-conf.xml”
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76. 4. Execute: $ java -jar target/metrics-*.jar
5. Invoke the following URLs via command line:
o curl -v http://localhost:8080/test/rand/500
o curl -v http://localhost:8080/test/total/10
o curl -v http://localhost:8080/test/echo/test
o curl -v http://localhost:8080/student/910760234V
o curl -v --data
"{'nic':'860766123V','firstName':'Jack','lastName':'Black','age':
29}" -H "Content-Type: application/json"
http://localhost:8080/student
o curl -v http://localhost:8080/student/860766123V
o curl -v http://localhost:8080/student
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77. o What is happening:
o Now, after the invocation from cURLs, some
information were sent from WSO2 Microservices
Server to WSO2 Data Analytics Server.
o The Metrics are also present in the command line
where you are running the jar:
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78. 78

79. @GET
@Path("/{nic}")
@Produces("application/json")
@Timed
@HTTPMonitoring
public Student getStudent(@PathParam("nic") String nic) {
return students.get(nic);
}
@POST
@Consumes("application/json")
@Metered
@HTTPMonitoring
public void addStudent(Student student) {
students.put(student.getNic(), student);
}
org.wso2.carbon.msf4j.example.service.StudentService.java

80. 80
<Agent>
<Name>Thrift</Name>
<DataEndpointClass>
org.wso2.carbon.databridge.agent.endpoint.thrift.ThriftDataEndpoint
</DataEndpointClass>
<TrustSore>client-truststore.jks</TrustSore>
<TrustSorePassword>wso2carbon</TrustSorePassword>
….
Thrift
This file is in charge to define how will msf4j communicate with DAS

81. https://localhost:9443/monitoring/
81

83. o http://kubernetes.io/v1.1/
o https://www.digitalocean.com/community/tutorials/an-introduction-to-
kubernetes
o https://insights.sei.cmu.edu/saturn/2015/11/defining-
microservices.html
o http://www.slideshare.net/afkham_azeez/wso2con-
2015usintroductiontomssv2?related=1
o http://www.slideshare.net/afkham_azeez/wso2conus-2015-
introduction-to-wso2-microservices-server-mss?related=2

84. 84

85. o http://wso2.com/products/microservices-server/
o Lightweight and fast runtime
o 6MB pack size
o Starts within 400ms
o Based on the new WSO2 Carbon 5.0 kernel
o ~25MB memory consumption for the WSO2 MSS framework
o Simple development, deployment, and monitoring
o WSO2 Developer Studio-based tooling for generating microservices projects starting from a Swagger API
definition
o Built-in metrics and analytics APIs via WSO2 Data Analytics Server
o Tracing of requests using a unique message ID
o High scalability and reliability
o Transport based on Netty 4.0
o JWT-based security
o Custom interceptors
o Streaming input and streaming output support
o Comprehensive samples demonstrating how to develop microservices applications
85

86. o Tutorial done!
o Next steps:
o Keep watching how WSO2 MSS will evolve
o Don’t miss our upcoming Webinars covering this and
even more
86

87. o Please, if you need to understand more, or want
to talk to one of our specialists to help you and
your company’s projects, please contact us
here:
o http://wso2.com/contact/
87

88. 88
@jedgarsilva
http://www.wso2.com
Edgar Silva
edgar@wso2.com

89. Contact us !