update TransactionController with transfer

http/transaction.http

@@ -15,3 +15,13 @@ Content-Type: application/json
   "account": "00000000-0000-0000-0000-000000000000",
   "amount": 1
 }
+
+### Withdrawal
+POST {{url}}/transfer
+Content-Type: application/json
+
+{
+  "account": "00000000-0000-0000-0000-000000000000",
+  "receiver": "00000000-0000-0000-0000-000000000000",
+  "amount": 1
+}

src/main/kotlin/ltd/lulz/controller/TransactionController.kt

@@ -5,6 +5,7 @@ import jakarta.validation.Valid
 import ltd.lulz.exception.AccountNotFoundException
 import ltd.lulz.exception.InsufficientFundsException
 import ltd.lulz.model.Transaction
+import ltd.lulz.model.Transfer
 import ltd.lulz.service.TransactionService
 import org.springframework.http.HttpStatus.CREATED
 import org.springframework.http.HttpStatus.INTERNAL_SERVER_ERROR
@@ -54,4 +55,19 @@ class TransactionController(
         }
         .doOnError { log.warn { "withdrawal account ${request.account}: " + it.localizedMessage } }
         .then()
+
+    @PostMapping("/transfer")
+    @ResponseStatus(CREATED)
+    fun transfer(
+        @Valid @RequestBody request: Transfer.Request,
+    ): Mono<Void> = transactionService.transfer(request.account, request.receiver, request.amount)
+        .onErrorResume {
+            when (it) {
+                is InsufficientFundsException -> Mono.error(ResponseStatusException(NOT_ACCEPTABLE))
+                is AccountNotFoundException -> Mono.error(ResponseStatusException(NOT_FOUND))
+                else -> Mono.error(ResponseStatusException(INTERNAL_SERVER_ERROR))
+            }
+        }
+        .doOnError { log.warn { "transfer account ${request.account}: " + it.localizedMessage } }
+        .then()
 }

src/test/kotlin/ltd/lulz/controller/TransactionControllerTest.kt

@@ -9,6 +9,7 @@ import ltd.lulz.exception.AccountNotFoundException
 import ltd.lulz.exception.InsufficientFundsException
 import ltd.lulz.model.AccountEntity
 import ltd.lulz.model.Transaction
+import ltd.lulz.model.Transfer
 import ltd.lulz.service.TransactionService
 import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
@@ -23,6 +24,7 @@ class TransactionControllerTest {
     companion object {
         val amount: BigDecimal = BigDecimal.valueOf(0.01)
         val uuid: UUID = UUID.fromString("00000000-0000-0000-0000-000000000000")
+        val receiver = UUID.fromString("00000000-0000-0000-0000-000000000001")
     }
 
     private val transactionService: TransactionService = mockk()
@@ -194,4 +196,92 @@ class TransactionControllerTest {
         // then
         result.expectStatus().is5xxServerError
     }
+
+    @Test
+    fun `transfer success`() {
+        // given
+        val request = Transfer.Request(uuid, receiver, amount)
+
+        every { transactionService.transfer(any(), any(), any()) } returns Mono.empty()
+
+        // when
+        val result = webTestClient.post()
+            .uri("/transfer")
+            .contentType(APPLICATION_JSON)
+            .bodyValue(request)
+            .exchange()
+
+        // then
+        result.expectStatus().isCreated
+    }
+
+    @Test
+    fun `transfer fail amount to small`() {
+        // given
+        val request = Transfer.Request(uuid, receiver, BigDecimal.valueOf(0.009))
+
+        // when
+        val result = webTestClient.post()
+            .uri("/transfer")
+            .contentType(APPLICATION_JSON)
+            .bodyValue(request)
+            .exchange()
+
+        // then
+        result.expectStatus().isBadRequest
+    }
+
+    @Test
+    fun `transfer insufficient Funds`() {
+        // given
+        val request = Transfer.Request(uuid, receiver, amount)
+
+        every { transactionService.transfer(any(), any(), any()) } returns Mono.error(InsufficientFundsException())
+
+        // when
+        val result = webTestClient.post()
+            .uri("/transfer")
+            .contentType(APPLICATION_JSON)
+            .bodyValue(request)
+            .exchange()
+
+        // then
+        result.expectStatus().isEqualTo(NOT_ACCEPTABLE)
+    }
+
+    @Test
+    fun `transfer account not found`() {
+        // given
+        val request = Transfer.Request(uuid, receiver, amount)
+
+        every { transactionService.transfer(any(), any(), any()) } returns Mono.error(AccountNotFoundException())
+
+        // when
+        val result = webTestClient.post()
+            .uri("/transfer")
+            .contentType(APPLICATION_JSON)
+            .bodyValue(request)
+            .exchange()
+
+        // then
+        result.expectStatus().isNotFound
+    }
+
+    @Test
+    fun `transfer default error`() {
+        // given
+        val request = Transfer.Request(uuid, receiver, amount)
+
+        every { transactionService.transfer(any(), any(), any()) } returns Mono.error(RuntimeException())
+
+        // when
+        val result = webTestClient.post()
+            .uri("/transfer")
+            .contentType(APPLICATION_JSON)
+            .bodyValue(request)
+            .exchange()
+
+        // then
+        result.expectStatus().is5xxServerError
+    }
 }