[20210904] (Kotlin) Custom Valid Annotation

[JuHyun419]

Kotlin - 커스텀 어노테이션(Valid)

• 기존 코드

import ...

@JsonNaming(PropertyNamingStrategies.SnakeCaseStrategy::class)
// @JsonNaming(PropertyNamingStrategy.SnakeCaseStrategy::class) deprecated
data class UserRequest(

        ...

        var createdAt: String? = null // yyyy-MM-dd HH:mm:ss
)

    /* StringFormatDateTime, Valid로 대체 */
    @AssertTrue(message = "생성일자의 패턴은 yyyy-MM-dd HH:mm:ss 여야 합니다.")
    private fun isValidCreatedAt(): Boolean {
        try {
            LocalDateTime.parse(this.createdAt, DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"))
            return true
        } catch (e: Exception) {
            return false
        }
    }

• Custom

/* annotation */
import org.juhyun.kotlinspringboot.valid.StringFormatDateTimeValid
import javax.validation.Constraint
import javax.validation.Payload
import kotlin.reflect.KClass

@Constraint(validatedBy = [StringFormatDateTimeValid::class])
@Target(
        AnnotationTarget.FIELD,
        AnnotationTarget.PROPERTY_GETTER,
        AnnotationTarget.PROPERTY_GETTER
)
@Retention(AnnotationRetention.RUNTIME)
@MustBeDocumented
annotation class StringFormatDateTime(
        val pattern: String = "yyyy-MM-dd HH:mm:ss",
        val message: String = "시간 형식이 유효하지 않습니다",
        val groups: Array<KClass<*>> = [],
        val payload: Array<KClass<out Payload>> = []
)


/* Valid Class */
import org.juhyun.kotlinspringboot.annotation.StringFormatDateTime
import java.lang.Exception
import java.time.LocalDateTime
import java.time.format.DateTimeFormatter
import javax.validation.ConstraintValidator
import javax.validation.ConstraintValidatorContext

class StringFormatDateTimeValid : ConstraintValidator<StringFormatDateTime, String> {

    private var pattern: String? = null

    override fun initialize(constraintAnnotation: StringFormatDateTime?) {
        this.pattern = constraintAnnotation?.pattern
    }

    // 유효성 검사
    override fun isValid(value: String?, context: ConstraintValidatorContext?): Boolean {
        try {
            LocalDateTime.parse(value, DateTimeFormatter.ofPattern(pattern))
            return true
        } catch (e: Exception) {
            return false
        }
    }

}


/* UserRequest */
@field:StringFormatDateTime(pattern = "yyyy-MM-dd HH:mm:ss", message = "패턴이 올바르지 않습니다.")
var createdAt: String? = null // yyyy-MM-dd HH:mm:ss