Example shows how to build a simple query language using JPA and Antlr4 for a REST API service.
Naive e-wallet domain model is used here:
User -< Wallet >- Currency
|
^
Transaction
Service allows to create and query transactions for pre-populated wallets.
Start a database:
./mvnw docker:start
Start a micro-service:
./mvnw clean spring-boot:run
Query transactions, for example those with amount less than or equal to 1500 USD:
curl -G "http://localhost:8080/v1/transactions" --data-urlencode "filter=amount le 1500 and to.currency.currencyCode eq 'USD'" | jq
Create a new transaction (change from and to values to ones from your database):
curl -d '{"from": "1571170777883", "to": "1571170777884", "amount": 45}' -H 'content-type: application/json' -X POST http://localhost:8080/v1/transactions | jq