Saga-dubbo-demo

This demo including three services:

Prerequisites

You will need:

run the following command to create docker images in saga project root folder.
```
mvn clean install -DskipTests -Pdocker -Pdemo
```
start the whole application up(including alpha server and three demo services)
```
./saga-dubbo-demo.sh up
```
Note: If you prefer to use MySQL as alpha's backend database, you need to try the following steps instead:
1. add dependency of mysql-connector-java in alpha/alpha-server/pom.xml
```
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
    </dependency>
```
1. re-generate saga's docker images in saga project root folder
```
mvn package -DskipTests -Pdocker -Pdemo
```
1. start application up in saga-dubbo-demo with the following command
```
	 cd ./saga-demo/saga-dubbo-demo
./saga-dubbo-demo.sh up-mysql
```
Note: If you want start alpha server and demon services separately, you can try the following steps:
1. start alpha server
```
    ./saga-dubbo-demo.sh up-alpha
```
1. when alpha server started complatelly, then start the demo services
```
    ./saga-dubbo-demo.sh up-demo
```
stop application
```
./saga-dubbo-demo.sh down
```

Use browser to run transaction demos: A:servicea B:serviceb C:servicec

A->B

 http://${host_address}:8071/serviceInvoke/Ab

A->B (A throw an exception)

 http://${host_address}:8071/serviceInvoke/AExceptionWhenAb

A->B (B throw an exception)

 http://${host_address}:8071/serviceInvoke/BExceptionWhenAb

A->B A->C

 http://${host_address}:8071/serviceInvoke/AbAc

A->B A->C (C throw an exception)

 http://${host_address}:8071/serviceInvoke/CExceptionWhenAbAc

A->B B->C

 http://${host_address}:8071/serviceInvoke/AbBc

A->B B->C (C throw an exception)

 http://${host_address}:8071/serviceInvoke/CExceptionWhenAbBc

Take the spring-demo debugging as a reference.