EDC Samples for eventing system

This repository provides examples of how to use the EDC connector event system which is explained in the developer documentation.

As source code, the repository Samples of Eclipse EDC has been cloned. To speed up the compilation process, only Transfer Samples has been used, so the rest of the examples have been removed.

Event sample

In this basic sample a service extension is created in the ExampleEventExtension.java file. Inside this extension the subscriber of the ExampleEventSubscriber() event is called. This subscriber is defined in the ExampleEventSubscriber.java file. For this sample, any event occurring in the connector will execute ExampleEventSubscriber() and the type of event that has produced its execution will be printed.

0. Prerequisites

Following the sample Write your first extension, the ExampleEventExtension.java and ExampleEventSubscriber.java files have been created inside the transfer/transfer-00-prerequisites/connector/src/main/java/org/eclipse/edc/sample/extension/event/ directory. The created extension has also been added to the org.eclipse.edc.spi.system.ServiceExtension file located in the transfer/transfer-00-prerequisites/connector/src/main/resources/META-INF/services/ directory.

Clone the modified repository with the event tag

git clone -b event https://github.com/johnnychoque/edc-conn-modif.git

1. Build and run the modified connector

Run the commands of Transfer sample 00: Prerequisites to build and execute the modified connector.

cd edc-conn-modif
./gradlew transfer:transfer-00-prerequisites:connector:build

Execute the connector as Provider for initial testing

java -Dedc.keystore=transfer/transfer-00-prerequisites/resources/certs/cert.pfx -Dedc.keystore.password=123456 -Dedc.fs.config=transfer/transfer-00-prerequisites/resources/configuration/provider-configuration.properties -jar transfer/transfer-00-prerequisites/connector/build/libs/connector.jar

2. Test the modified connector

Following the sample Transfer sample 01: Negotiation, open another terminal and create an asset on the Provider by running:

curl -d @transfer/transfer-01-negotiation/resources/create-asset.json \
  -H 'content-type: application/json' http://localhost:19193/management/v3/assets \
  -s | jq

The following message will be displayed on the terminal:

>>>>>>>>>>>>>> EVENT >>>>>>>>>>>>>
org.eclipse.edc.connector.controlplane.asset.spi.event.AssetCreated@7fb52601

Sending http request when an event occurs

This sample extends the functionality of the event subscriber previously created by sending an http request to a test server every time an event occurs.

The okhttp3 and EdcHttpClient libraries are used to create the http requests. The EdcHttpClient library is a wrapper that uses okhttp3 to send the http requests in synchronous or asynchronous mode, but okhttp3 is also used to build the requests.

A new service extension NegotiationEventExtention.java and a new event subscriber AgreementReached.java are created. The org.eclipse.edc.edc.spi.system.ServiceExtension file is modified to include the new service extension NegotiationEventExtension instead of the previous ExampleEventExtension.

Inside the event subscriber AgreementReached is the sendTestMessage() method, which sends the http request to the test server running at http://localhost:3000/. Each time an event occurs the subscriber AgreementReached calls the sendTestMessage() method, which sends the JSON (“access_token”, “token”) to the server.

0. Prerequisites

Clone the modified repository with the request tag

git clone -b request https://github.com/johnnychoque/edc-conn-modif.git

Build the modified comector.

cd edc-conn-modif
./gradlew transfer:transfer-00-prerequisites:connector:build

Install all the dependencies of test server

cd server-test
npm install

1. Test the modified connector

In a terminal run the connector as Provider for initial testing:

cd edc-conn-modif
java -Dedc.keystore=transfer/transfer-00-prerequisites/resources/certs/cert.pfx -Dedc.keystore.password=123456 -Dedc.fs.config=transfer/transfer-00-prerequisites/resources/configuration/provider-configuration.properties -jar transfer/transfer-00-prerequisites/connector/build/libs/connector.jar

In another terminal run the test server:

cd server-test
npm start

Open again another terminal and create an asset on the Provider:

curl -d @transfer/transfer-01-negotiation/resources/create-asset.json \
  -H 'content-type: application/json' http://localhost:19193/management/v3/assets \
  -s | jq

The following message will be displayed on the terminal:

>>>>>>>>>>>>>> EVENT >>>>>>>>>>>>>
org.eclipse.edc.connector.controlplane.asset.spi.event.AssetCreated@27a91331
{"access_token":"token"}

The terminal where the test server is running will also display the message {“access_token”: “token”}. This is the message sent by the http POST request of the sendTestMessage() method.