Implementation of the RESTful API (including data model and the backing implementation) for money transfers between accounts.
To serve RESTful API application uses akka-http library with it's routing DSL.
To implement consistent transfers Akka persistent actors was used. So, the application demonstrates event-sourced way to implement the task using actors.
Application is distributed along with the gradle wrapper to make it easy to build and run.
To start the server just type ./gradlew run. As a default setting it will start the application listenning on the http://localhost:8090/.
For all calls it's assumed that client will provide allowed account and transfer identifiers as UUID: it's requered to generate one for creation operations and use existed one to manage of entities.
In examples only happy paths will be presented, but the service is tested to be ready for incorrect inputs and states to make a deserved response.
Let create the source account A:
curl -X POST \
http://localhost:8090/accounts \
-H 'Content-Type: application/json' \
-d '{
"account_id": "132e4367-e89b-13d5-a456-556d42440000",
"name": "A"
}'
Let create the target account B:
curl -X POST \
http://localhost:8090/accounts \
-H 'Content-Type: application/json' \
-d '{
"account_id": "232e4367-e89b-13d5-a456-556d42440000",
"name": "B"
}'
curl -X POST \
http://localhost:8090/accounts/132e4367-e89b-13d5-a456-556d42440000/deposit \
-H 'Content-Type: application/json' \
-d '{
"transfer_id": "133e4147-e19b-23d3-d455-253222448010",
"amount": 100.0
}'
curl -X POST \
http://localhost:8090/transfers \
-H 'Content-Type: application/json' \
-d '{
"transfer_id": "433e4147-e19b-23d3-d455-253222448010",
"source_account_id": "132e4367-e89b-13d5-a456-556d42440000",
"target_account_id": "232e4367-e89b-13d5-a456-556d42440000",
"amount": 30.0
}'
As a success, you will see:
{
"transfer_id": "433e4147-e19b-23d3-d455-253222448010",
"source_account_id": "132e4367-e89b-13d5-a456-556d42440000",
"target_account_id": "232e4367-e89b-13d5-a456-556d42440000",
"amount": 30,
"status": "completed"
}
Let see the state of the accouunt A:
curl -X GET \
http://localhost:8090/accounts/132e4367-e89b-13d5-a456-556d42440000
Response:
{
"account_id": "132e4367-e89b-13d5-a456-556d42440000",
"name": "A",
"balance": 70
}
Let see the state of the accouunt B:
curl -X GET \
http://localhost:8090/accounts/232e4367-e89b-13d5-a456-556d42440000
Response:
{
"account_id": "232e4367-e89b-13d5-a456-556d42440000",
"name": "B",
"balance": 30
}
As you can see 30 units was transfered from account A to the account B as we had requested.
It's also alowed to retrieve transfer state:
curl -X GET \
http://localhost:8090/transfers/433e4147-e19b-23d3-d455-253222448010
Response:
{
"transfer_id": "433e4147-e19b-23d3-d455-253222448010",
"source_account_id": "132e4367-e89b-13d5-a456-556d42440000",
"target_account_id": "232e4367-e89b-13d5-a456-556d42440000",
"amount": 30,
"status": "completed"
}