Feature: (BRD-74) 액세스토큰 인증 기능 추가

board-system-external/external-security/src/main/kotlin/com/ttasjwi/board/system/auth/domain/external/spring/security/BearerTokenResolver.kt

@@ -0,0 +1,20 @@
+package com.ttasjwi.board.system.auth.domain.external.spring.security
+
+import com.ttasjwi.board.system.auth.domain.external.spring.security.exception.InvalidAuthorizationHeaderFormatException
+import jakarta.servlet.http.HttpServletRequest
+import org.springframework.http.HttpHeaders
+
+class BearerTokenResolver {
+
+    private val bearerTokenHeaderName = HttpHeaders.AUTHORIZATION
+
+    fun resolve(request: HttpServletRequest): String? {
+        val authorizationHeader = request.getHeader(this.bearerTokenHeaderName) ?: return null
+
+        if (!authorizationHeader.startsWith("Bearer ", ignoreCase = true)) {
+            throw InvalidAuthorizationHeaderFormatException()
+        }
+        return authorizationHeader.substring(7)
+    }
+
+}

board-system-external/external-security/src/main/kotlin/com/ttasjwi/board/system/auth/domain/external/spring/security/exception/InvalidAuthorizationHeaderFormatException.kt

@@ -0,0 +1,12 @@
+package com.ttasjwi.board.system.auth.domain.external.spring.security.exception
+
+import com.ttasjwi.board.system.core.exception.CustomException
+import com.ttasjwi.board.system.core.exception.ErrorStatus
+
+class InvalidAuthorizationHeaderFormatException : CustomException(
+    status = ErrorStatus.UNAUTHENTICATED,
+    code = "Error.InvalidAuthorizationHeaderFormat",
+    args = emptyList(),
+    source = "authorizationHeader",
+    debugMessage = "잘못된 Authorization 헤더 형식입니다. 토큰값을 Authorization 헤더에 'Bearer [토큰값]' 형식으로 보내주세요."
+)

board-system-external/external-security/src/test/kotlin/com/ttasjwi/board/system/auth/domain/external/spring/security/BearerTokenResolverTest.kt

@@ -0,0 +1,66 @@
+package com.ttasjwi.board.system.auth.domain.external.spring.security
+
+import com.ttasjwi.board.system.auth.domain.external.spring.security.exception.InvalidAuthorizationHeaderFormatException
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import jakarta.servlet.http.HttpServletRequest
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
+import org.springframework.http.HttpHeaders
+
+@DisplayName("BearerTokenResolver: Authorization 헤더의 Bearer 뒤에 위치한 토큰값을 분리한다.")
+class BearerTokenResolverTest {
+    private lateinit var bearerTokenResolver: BearerTokenResolver
+
+    @BeforeEach
+    fun setup() {
+        bearerTokenResolver = BearerTokenResolver()
+    }
+
+    @Test
+    @DisplayName("헤더값이 유효하다면, 토큰값이 성공적으로 분리된다.")
+    fun testSuccess() {
+        // given
+        val request = mockk<HttpServletRequest>()
+        every { request.getHeader(HttpHeaders.AUTHORIZATION) } returns "Bearer validToken123"
+
+
+        // when
+        val token = bearerTokenResolver.resolve(request)
+
+        // then
+        assertThat(token).isEqualTo("validToken123")
+        verify { request.getHeader(HttpHeaders.AUTHORIZATION) }
+    }
+
+    @Test
+    @DisplayName("Authorization 헤더값이 없을 경우 null 이 반환된다.")
+    fun authorizationHeaderNull() {
+        // given
+        val request = mockk<HttpServletRequest>()
+        every { request.getHeader(HttpHeaders.AUTHORIZATION) } returns null
+
+        // when
+        val token = bearerTokenResolver.resolve(request)
+
+        // then
+        assertThat(token).isNull()
+    }
+
+    @Test
+    @DisplayName("Authorization 헤더값이 Bearer 로 시작하지 않으면 예외가 발생한다.")
+    fun testBadAuthorizationHeader() {
+        // given
+        val request = mockk<HttpServletRequest>()
+        every { request.getHeader(HttpHeaders.AUTHORIZATION) } returns "Basic abc123"
+
+        // when
+        // then
+        assertThrows<InvalidAuthorizationHeaderFormatException> { bearerTokenResolver.resolve(request) }
+        verify { request.getHeader(HttpHeaders.AUTHORIZATION) }
+    }
+}

board-system-external/external-security/src/test/kotlin/com/ttasjwi/board/system/auth/domain/external/spring/security/exception/InvalidAuthorizationHeaderFormatExceptionTest.kt

@@ -0,0 +1,24 @@
+package com.ttasjwi.board.system.auth.domain.external.spring.security.exception
+
+import com.ttasjwi.board.system.core.exception.ErrorStatus
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
+
+@DisplayName("InvalidAuthorizationHeaderFormatException: Authorization 헤더값 포맷이 잘못된 형식일 때 발생하는 예외")
+class InvalidAuthorizationHeaderFormatExceptionTest {
+
+    @Test
+    @DisplayName("예외 기본값 테스트")
+    fun test() {
+        val exception = InvalidAuthorizationHeaderFormatException()
+
+        assertThat(exception.status).isEqualTo(ErrorStatus.UNAUTHENTICATED)
+        assertThat(exception.code).isEqualTo("Error.InvalidAuthorizationHeaderFormat")
+        assertThat(exception.source).isEqualTo("authorizationHeader")
+        assertThat(exception.args).isEmpty()
+        assertThat(exception.message).isEqualTo(exception.debugMessage)
+        assertThat(exception.cause).isNull()
+        assertThat(exception.debugMessage).isEqualTo("잘못된 Authorization 헤더 형식입니다. 토큰값을 Authorization 헤더에 'Bearer [토큰값]' 형식으로 보내주세요.")
+    }
+}

build.gradle.kts

@@ -42,6 +42,7 @@ subprojects {
 
         implementation(Dependencies.KOTLIN_REFLECT.fullName)
         testImplementation(Dependencies.SPRING_BOOT_TEST.fullName)
+        testImplementation(Dependencies.MOCKK.fullName)
     }
 
     tasks.getByName("bootJar") {

buildSrc/src/main/kotlin/Dependencies.kt

@@ -33,8 +33,10 @@ enum class Dependencies(
     YAML_RESOURCE_BUNDLE(groupId = "dev.akkinoc.util", artifactId = "yaml-resource-bundle", version = "2.13.0"),
 
     // email-format-check
-    COMMONS_VALIDATOR(groupId="commons-validator", artifactId ="commons-validator" , version="1.9.0");
+    COMMONS_VALIDATOR(groupId="commons-validator", artifactId ="commons-validator" , version="1.9.0"),
 
+    // mockk
+    MOCKK(groupId="io.mockk", artifactId="mockk" , version="1.13.13");
 
     val fullName: String
         get() {