Decision System for Data and Computation Movement

The goal of the component consists in selecting the best data and computation movement actions to be adopted in order to restore the level of data quality, quality of service and security defined by the application developer.

Input

Concrete blueprint (Goal model)
List of violated requirements

Output

List of data and computation actions (adaptation actions)

List of functionalities

/v2/CheckStatus
- description: the api shows the number of active VDCs (goal models)
- HTTP call: GET
- input
  - list of violated requirements
- output
  - HTTP code 200 if goal model correcly parsed
/v2/NotifyViolation
- description: the method receives in input a list of violations.
- HTTP call: POST
- input
  - list of violated requirements
- output
  - HTTP code 200 if goal model correcly parsed
  - HTTP code 500 if problems occurred
/v2/AddVDC
- description: the method receives in input the concrete blueprint of the VDC deployed.
- HTTP call: POST
- input
  - concrete blueprint
- output
  - HTTP code 200 if goal model correcly parsed
  - HTTP code 500 if problems occurred
/v2/Reset
- description: the method reset the internal statius of the software
- HTTP call: GET
- input
  - empty
- output
  - HTTP code 200

Implementation language

Java

Installation

In order to deploy the DS4M it is not mandatory to compile the code since an already compiled version of the software is already provided in /target/ROOT.war. If you don't want to compile the source code, skip step Compilation.

Requirements for deployment

In order to be executed, this component requires the following elements to be installed:

JRE 8
Apache Tomcat 8.5

Requirements for copiling the code

JRE 8
Maven

Compilation

install Apache Tomcat
Download the source code from this repository
Copile it using maven:
with a shell navigate to the main folder and use the command mvn package
compile using eclipse
import the prioject usinh eclipse (oxygen, with pligin for maven)
right click on the main project and run maven install

Deployment

the file war file /target/ROOT.war creted with maven should be moved to the webapps folder of Apache Tomcat, if it is not the case, move it manually
Start Apache Tomcat

Check deployment

To test if the application is deployed correctly:

open a browser
go to address:port/NotifyViolation
a web page saying that the service is up and running should be displayed.

address: address of the machine where tomcat is installed (localhost,depending on the settings, you may need to add /ROOT at the end fo the address

port: port of the application, if no port forwarding has been specified, it is 8080

Deployment with Doker

It is possible to find a doker container boundled with the last version of DS4M here. the tag to use is production. In this case, you need docker to be installed in your computer. Once docker is installed, run on your comman line

docker run -d \
  --name DS4M \
  -p 30003:30003 \
  -v /Users/mattia/_etc/ditas/:/etc/ditas/ \
  -v /Users/mattia/_var/ditas/vdm/:/var/ditas/vdm/ \
  ditas/decision-system-for-data-and-computation-movement:production

This will create a running container listening on port 30003.

DS4M saves the status of the application and read configuration in two permanet folders. <path to a local folder containing configuration file> must contain a file DS4M_movementClasses.json that contains the descriprtion on adaptation action classes. An example of this file can be found here

<path to a empty local folder>:/var/ditas/vdm/ must contain an empty folder DS4M. If this folder is not provided the DS4M will still work, but is a completely stateless mode (i.e. it will not save nor the status of the client nor the status of the VDCs ( goal models) provided).

To check if DS4M is up and running open a browser and go to http://localhost:30003/v2/CheckStatus.

To check the logs

identify the container id with docker container ps -all
show the loigs with docker logs <container id>

the output should be similar to the next one

07-Mar-2020 12:12:12.493 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
DS4M: V2.3
BootConfigurator: folder structure partially not present, created.
BootConfigurator: status file does not exists, importing concrete blueprints
BootConfigurator: imported 0 blueprints
[...]
07-Mar-2020 12:12:12.883 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-apr-30003"]
07-Mar-2020 12:12:12.895 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-apr-8009"]
07-Mar-2020 12:12:12.897 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 2416 ms

clean up

To stop the container execute docker container stop <container ID>

To remove the container execute docker container rm <container ID>

To show the images execute docker images

To remove the images excute docker rmi <image ID> you can safely remove all images, if you are using Docker only for DS4M.

Test DS4M

To test DS4M you can use the files in /testResources, or run the Junit tests.

License

The project is under Apache 2.0 license. You can find the license here.

Acknowledge

This is being developed for the DITAS Project: https://www.ditas-project.eu/

DITAS-Project/decision-system-for-data-and-computation-movement