Fix transaction sum queries

src/main/kotlin/com/wbrawner/budgetserver/account/AccountController.kt

@@ -48,7 +48,7 @@ class AccountController @Autowired constructor(
             accountRepository.findByUsersContainsAndId(getCurrentUser()!!, id)
                     .orElse(null)
                     ?.let {
-                        ResponseEntity.ok(AccountBalanceResponse(it.id!!, transactionRepository.sumBalanceByAccount(it)))
+                        ResponseEntity.ok(AccountBalanceResponse(it.id!!, transactionRepository.sumBalanceByAccountId(it.id)))
                     } ?: ResponseEntity.notFound().build()
 
     @PostMapping("/new", consumes = [MediaType.APPLICATION_JSON_VALUE], produces = [MediaType.APPLICATION_JSON_VALUE])

src/main/kotlin/com/wbrawner/budgetserver/category/Category.kt

@@ -36,6 +36,8 @@ data class CategoryResponse(
         )
 }
 
+data class CategoryBalanceResponse(val id: Long, val balance: Long)
+
 data class NewCategoryRequest(
         val title: String,
         val description: String?,

src/main/kotlin/com/wbrawner/budgetserver/category/CategoryController.kt

@@ -44,6 +44,15 @@ class CategoryController @Autowired constructor(
         return  ResponseEntity.ok(CategoryResponse(category))
     }
 
+    @GetMapping("/{id}/balance", produces = [MediaType.APPLICATION_JSON_VALUE])
+    @ApiOperation(value = "getCategoryBalance", nickname = "getCategoryBalance", tags = ["Categories"])
+    fun getCategoryBalance(@PathVariable id: Long): ResponseEntity<CategoryBalanceResponse> {
+        val category = categoryRepository.findById(id).orElse(null) ?: return ResponseEntity.notFound().build()
+        accountRepository.findByUsersContainsAndCategoriesContains(getCurrentUser()!!, category).orElse(null)
+                ?: return ResponseEntity.notFound().build()
+        return ResponseEntity.ok(CategoryBalanceResponse(category.id!!, transactionRepository.sumBalanceByCategoryId(category.id)))
+    }
+
     @Transactional
     @PostMapping("/new", consumes = [MediaType.APPLICATION_JSON_VALUE], produces = [MediaType.APPLICATION_JSON_VALUE])
     @ApiOperation(value = "newCategory", nickname = "newCategory", tags = ["Categories"])

src/main/kotlin/com/wbrawner/budgetserver/transaction/TransactionRepository.kt

@@ -13,7 +13,13 @@ interface TransactionRepository: PagingAndSortingRepository<Transaction, Long> {
     fun findAllByAccountAndCategory(account: Account, category: Category): List<Transaction>
     @Query(
             nativeQuery = true,
-            value = "SELECT (COALESCE((SELECT SUM(amount) from transaction WHERE expense = 0), 0)) - (COALESCE((SELECT SUM(amount) from transaction WHERE expense = 1), 0));"
+            value = "SELECT (COALESCE((SELECT SUM(amount) from transaction WHERE account_id = :accountId AND expense = 0), 0)) - (COALESCE((SELECT SUM(amount) from transaction WHERE account_id = :accountId AND expense = 1), 0));"
     )
-    fun sumBalanceByAccount(account: Account): Long
+    fun sumBalanceByAccountId(accountId: Long): Long
+
+    @Query(
+            nativeQuery = true,
+            value = "SELECT (COALESCE((SELECT SUM(amount) from transaction WHERE category_id = :categoryId AND expense = 0), 0)) - (COALESCE((SELECT SUM(amount) from transaction WHERE category_id = :categoryId AND expense = 1), 0));"
+    )
+    fun sumBalanceByCategoryId(categoryId: Long): Long
 }