fix: about kotlinx.serialize

src/backend/build.gradle.kts

@@ -1,12 +1,13 @@
 plugins {
     kotlin("jvm") version "2.3.21"
     kotlin("plugin.spring") version "2.3.21"
+    id("org.jetbrains.kotlin.plugin.serialization") version "2.4.20-RC"
     id("org.springframework.boot") version "4.1.0"
     id("io.spring.dependency-management") version "1.1.7"
 }
 
 group = "club.itstudio"
-version = "0.1.0"
+version = "0.1.1"
 description = "itmanager"
 
 java {

src/backend/src/main/kotlin/club/itstudio/itmanager/config/SerializationConfig.kt

@@ -1,5 +1,6 @@
 package club.itstudio.itmanager.config
 
+import club.itstudio.itmanager.utils.customSerializersModule
 import kotlinx.serialization.json.Json
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
@@ -9,6 +10,7 @@ class SerializationConfig {
 
     @Bean
     fun kotlinxSerializationJson(): Json = Json {
+        serializersModule = customSerializersModule
         ignoreUnknownKeys = true
         isLenient = true
         encodeDefaults = false

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/FinanceRecord.kt

@@ -6,6 +6,7 @@ import com.baomidou.mybatisplus.annotation.TableName
 import club.itstudio.itmanager.entity.DataCopy
 import club.itstudio.itmanager.entity.enums.FinanceRecordType
 import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Contextual
 import kotlinx.serialization.Serializable
 import java.math.BigDecimal
 
@@ -17,7 +18,7 @@ data class FinanceRecord(
     val recordNo: String? = null,
     val type: FinanceRecordType = FinanceRecordType.OTHER,
     val relatedItemId: Long? = null,
-    val amount: BigDecimal = BigDecimal.ZERO,
+    val amount: @Contextual BigDecimal = BigDecimal.ZERO,
     val currency: String = "CNY",
     val vendor: String? = null,
     val occurredAt: LocalDateTime? = null,

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/Item.kt

@@ -6,6 +6,7 @@ import com.baomidou.mybatisplus.annotation.TableName
 import club.itstudio.itmanager.entity.DataCopy
 import kotlinx.datetime.LocalDate
 import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Contextual
 import kotlinx.serialization.Serializable
 import java.math.BigDecimal
 
@@ -23,7 +24,7 @@ data class Item(
     val totalQuantity: Int = 0,
     val availableQuantity: Int = 0,
     val unit: String = "件",
-    val price: BigDecimal? = null,
+    val price: @Contextual BigDecimal? = null,
     val purchaseDate: LocalDate? = null,
     val supplier: String? = null,
     val status: String = "normal",

src/backend/src/main/kotlin/club/itstudio/itmanager/utils/BigDecimalSerializer.kt

@@ -0,0 +1,35 @@
+package club.itstudio.itmanager.utils
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.SerializationException
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+import kotlinx.serialization.json.JsonDecoder
+import kotlinx.serialization.json.JsonPrimitive
+import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.contextual
+import java.math.BigDecimal
+
+object BigDecimalSerializer : KSerializer<BigDecimal> {
+    override val descriptor: SerialDescriptor =
+        PrimitiveSerialDescriptor("BigDecimal", PrimitiveKind.STRING)
+
+    override fun serialize(encoder: Encoder, value: BigDecimal) {
+        encoder.encodeString(value.toPlainString())
+    }
+
+    override fun deserialize(decoder: Decoder): BigDecimal {
+        val element = (decoder as JsonDecoder).decodeJsonElement()
+        if (element !is JsonPrimitive) {
+            throw SerializationException("Expected JSON primitive, got $element")
+        }
+        return element.content.toBigDecimal()
+    }
+}
+
+val customSerializersModule = SerializersModule {
+    contextual(BigDecimalSerializer)
+}