add create product api-endpoint

src/main/kotlin/com/example/demo/controllers/ProductController.kt

@@ -1,11 +1,14 @@
 package com.example.demo.controllers
 
 import com.example.demo.exceptions.NotFoundException
+import com.example.demo.models.Product
 import com.example.demo.provider.ProductRepository
+import com.example.demo.requests.CreateProductRequest
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.encodeToJsonElement
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.web.bind.annotation.*
+import java.time.OffsetDateTime
 import java.util.*
 
 @RestController
@@ -22,4 +25,26 @@ class ProductController(
 
         return Json.encodeToJsonElement(value = product).toString()
     }
+
+    @PostMapping(value = [""], consumes = ["application/json"], produces = ["application/json"])
+    @ResponseBody
+    fun createProduct(
+        @RequestBody product: CreateProductRequest
+    ): String {
+        val productModel = Product(
+            id = null,
+            guid = UUID.randomUUID(),
+            name = product.name,
+            description = product.description,
+            price = product.price,
+            createdAt = OffsetDateTime.now(),
+            updatedAt = null,
+        )
+
+        val saved = productRepository.save(productModel)
+
+        return Json.encodeToJsonElement(value = saved).toString()
+    }
+
+    // todo delete with soft-delete
 }

src/main/kotlin/com/example/demo/models/Product.kt

@@ -4,9 +4,9 @@ package com.example.demo.models
 import com.example.demo.models.serializables.OffsetDateTimeSerialization
 import com.example.demo.models.serializables.UuidSerialization
 import com.example.demo.utils.roundTo
-import jakarta.persistence.Column
-import jakarta.persistence.Id
 import kotlinx.serialization.Serializable
+import org.springframework.data.annotation.Id
+import org.springframework.data.relational.core.mapping.Column
 import org.springframework.data.relational.core.mapping.Table
 import java.time.OffsetDateTime
 import java.util.*
@@ -14,17 +14,18 @@ import java.util.*
 @Table(value = "product", schema = "public")
 @Serializable
 data class Product(
-    @Id var id: Long,
+    @Id
+    val id: Long?,
     @Serializable(with = UuidSerialization::class)
     val guid: UUID,
     val name: String,
     val description: String?,
-    val price: Int,
+    val price: Long,
     @Serializable(with = OffsetDateTimeSerialization::class)
-    @Column(name = "created_at")
+    @Column(value = "created_at")
     val createdAt: OffsetDateTime,
     @Serializable(with = OffsetDateTimeSerialization::class)
-    @Column(name = "updated_at")
+    @Column(value = "updated_at")
     val updatedAt: OffsetDateTime?,
 ) {
     fun getPriceDouble(): Double = (price.toDouble() / 100).roundTo(2)

src/main/kotlin/com/example/demo/provider/MockedShopProvider.kt

@@ -38,7 +38,7 @@ class MockedShopProvider: ShopProvider {
             guid = UUID.randomUUID(),
             name = name,
             description = null,
-            price = (price * 100).toInt(),
+            price = (price * 100).toLong(),
             createdAt = OffsetDateTime.now(),
             updatedAt = null,
         )

src/main/kotlin/com/example/demo/requests/CreateProductRequest.kt

@@ -0,0 +1,7 @@
+package com.example.demo.requests
+
+data class CreateProductRequest(
+    val name: String,
+    val description: String?,
+    val price: Long,
+)