Be-Well

A sample cordapp to demonstrate the use of queryable states in corda through the use-case of a health and wellness application.

Be-well represents a network with two kinds of participants - user brokers and wellness providers. User brokers can be any organization that offers to manage user information and gives them access to the network. Wellness providers may range from fitness and sports centers to health clinics that are willing to work with clients and their health. The environment may be visualized with various brokers interacting with different wellness providers to offer services to clients. This application presents a simplified version of this with three features - creation of wellness records, updates and wellness score metrics.

The contracts module defines the wellness contract that contains the attributes, commands and corresponding verification for transactions. Three flows defined in the cordapp module capture the features mentioned above - create, update and wellness scores. Additionally the cordapp also includes a basic web api to interact with a sample deployment.

Pre-Requisites

You will need the following installed on your machine before you can start:

• JDK 8 installed and available on your path (Minimum version: 1.8_131).
• IntelliJ IDEA (Minimum version 2017.1)
• git
• Optional: h2 web console (download the "platform-independent zip")

For IDE, compilation and JVM version issues, see the Troubleshooting page on the Corda docsite.

Getting Set Up

To get started, clone this repository with:

 git clone https://github.com/shinobis/be-well.git

And change directories to the newly cloned repo:

 cd be-well

Flows

• Create Wellness Flow: creates a new wellness state for a single user.
• Update Wellness Flow: to update the wellness details of a user.
• Score Wellness Flow: retrieves consumed and current states to generate a wellness score.

Building the Cordapp:

Unix:

 ./gradlew deployNodes

Windows:

 gradlew.bat deployNodes

Note: You'll need to re-run this build step after making any changes to the cordapps for these to take effect on the node.

Running the Nodes

Once the build finishes, change directories to the folder where the newly built nodes are located:

 cd build/nodes

The Gradle build script will have created a folder for each node. You'll see three folders, one for each node and a runnodes script. You can run the nodes with:

Unix:

 ./runnodes --log-to-console --logging-level=DEBUG

Windows:

runnodes.bat --log-to-console --logging-level=DEBUG

You can also start each node individually by changing into the node's directory and running the corda jar.

java -jar corda.jar

You should now have three Corda nodes running on your machine serving the cordapps.

When the nodes have booted up, you should see a message like the following in the console:

 Node started up and registered in 5.007 sec

Running the web servers:

The runnodes script starts up the webservers for each node. However, to individually start up the web server, run the web server jar from the node directory.

java -jar corda-webserver.jar

Interacting with the nodes

Use a tool such as Postman or curl (command line), to view data as well as run the various flows.

You can check the identity of node for each webserver using the identity endpoint.

curl http://localhost:10007/api/wellness/identity

To see available states in the node's vault use:

curl http://localhost:10007/api/wellness/vault

Here are sample commands for the three flows:

Create Wellness Flow

Unix:

curl --header "Content-Type: application/json" --request POST --data '{ "provider" : "First Wellness", "wellnessData" : { "sex" : "male", "age" : "28" } }' http://localhost:10007/api/wellness/create-wellness

Windows:

curl --header "Content-Type: application/json" --request POST --data "{ \"provider\" : \"First Wellness\", \"wellnessData\" : { \"sex\" : \"male\", \"age\" : \"28\" } }" http://localhost:10007/api/wellness/create-wellness

You should see a message similar to one below:

Added a new wellness report for account id 23562a68-51ba-412d-bd89-82c0f1405e1c in transaction 49A0179AC27B5F898B5A4AFBD71D4FDAB6D2C970B58B9B92D7A92DB60823D435 committed to ledger.

Update Wellness Flow

Unix:

curl --header "Content-Type: application/json" --request POST --data '{ "accountId" : "23562a68-51ba-412d-bd89-82c0f1405e1c", "wellnessData" : { "sex" : "male", "age" : "28", "height" : "168", "weight" : "82", "heartRate" : "60" } }' http://localhost:10007/api/wellness/update-wellness

Windows:

curl --header "Content-Type: application/json" --request POST --data "{ \"accountId\" : \"23562a68-51ba-412d-bd89-82c0f1405e1c\", \"wellnessData\" : { \"sex\" : \"male\", \"age\" : \"28\", \"height\" : \"168\", \"weight\" : \"82\", \"heartRate\" : \"60\"} }" http://localhost:10007/api/wellness/update-wellness

You should see a message similar to one below:

Updated wellness report for account id 23562a68-51ba-412d-bd89-82c0f1405e1c in transaction 1F3B6540CF1851E44C04BE094AC8CBDF6A64685E3E76E74028D9D90172E15AC5 committed to ledger.

Score Wellness Flow

Unix:

curl --header "Content-Type: text/plain" --request POST --data 23562a68-51ba-412d-bd89-82c0f1405e1c http://localhost:10007/api/wellness/score-wellness

Windows:

curl --header "Content-Type: text/plain" --request POST --data 23562a68-51ba-412d-bd89-82c0f1405e1c http://localhost:10007/api/wellness/score-wellness

You should see a message similar to one below:

Added new score for account id 23562a68-51ba-412d-bd89-82c0f1405e1c in transaction A3F5303CB126AC079A6AEA98AD82E14F36C2B60A494CB6534BD2B4366C38EAF0 committed to ledger.

Suggestions and feedback are welcome.