feature: add error message to unparseable interval by using bean vali…

…dation annotation #46

ohsome-contributions-stats-service: 'Consider introducing 'Jakarta Bean validation' standard '
#46

src/main/kotlin/org/heigit/ohsome/now/statsservice/ExceptionHandler.kt

@@ -6,7 +6,9 @@ import org.springframework.web.bind.annotation.ExceptionHandler
 import org.springframework.web.bind.annotation.ResponseStatus
 
 
+@Deprecated("is handled via jakarta bean validation annotations now")
 data class UnparsableISO8601StringException(override val message: String? = null) : Exception(message)
+
 data class ISO8601TooSmallException(override val message: String? = null) : Exception(message)
 
 @ControllerAdvice

src/main/kotlin/org/heigit/ohsome/now/statsservice/Validations.kt

@@ -4,11 +4,15 @@ import jakarta.validation.Constraint
 import jakarta.validation.ConstraintValidator
 import jakarta.validation.ConstraintValidatorContext
 import jakarta.validation.Payload
+import org.heigit.ohsome.now.statsservice.utils.isParseableISO8601String
+import kotlin.annotation.AnnotationRetention.RUNTIME
+import kotlin.annotation.AnnotationTarget.TYPE
+import kotlin.annotation.AnnotationTarget.VALUE_PARAMETER
 import kotlin.reflect.KClass
 
 
-@Target(AnnotationTarget.VALUE_PARAMETER, AnnotationTarget.TYPE)
-@Retention(AnnotationRetention.RUNTIME)
+@Target(VALUE_PARAMETER, TYPE)
+@Retention(RUNTIME)
 @Constraint(validatedBy = [HashtagValidator::class])
 annotation class ValidHashtag(
     val message: String = "Hashtag must not be '*'",
@@ -23,3 +27,20 @@ class HashtagValidator : ConstraintValidator<ValidHashtag, String> {
 
 }
 
+
+
+@Target(VALUE_PARAMETER, TYPE)
+@Retention(RUNTIME)
+@Constraint(validatedBy = [ISO8601StringIntervalValidator::class])
+annotation class ParseableInterval(
+    val message: String = "Invalid ISO8601 string as interval.",
+    val groups: Array<KClass<*>> = [],
+    val payload: Array<KClass<out Payload>> = []
+)
+
+class ISO8601StringIntervalValidator : ConstraintValidator<ParseableInterval, String> {
+
+    override fun isValid(interval: String, context: ConstraintValidatorContext?) = isParseableISO8601String(interval)
+
+}
+

src/main/kotlin/org/heigit/ohsome/now/statsservice/stats/StatsController.kt

@@ -109,6 +109,7 @@ class StatsController {
 
         @Parameter(description = "the granularity defined as Intervals in ISO 8601 time format eg: P1M")
         @RequestParam(name = "interval", defaultValue = "P1M", required = false)
+        @ParseableInterval
         interval: String,
 
         @Parameter(description = "A comma separated list of countries, can also only be one country")

src/main/kotlin/org/heigit/ohsome/now/statsservice/utils/StringUtilities.kt

@@ -35,17 +35,22 @@ fun String.replaceTime() = this
 
 
 fun validateIntervalString(interval: String) {
-    checkIfStringIsParsable(interval)
+//    checkIfStringIsParsable(interval)
     checkIfDurationIsBiggerThanOneMinute(interval)
 }
 
-//TODO: consider replacing with jakarta bean validation annotations instead of throwing exception
+@Deprecated("is handled via jakarta bean validation annotations now")
 fun checkIfStringIsParsable(interval: String) {
-    if (!interval.matches(Regex("^P(?!\$)(\\d+Y)?(\\d+M)?(\\d+W)?(\\d+D)?(T(?=\\d)(\\d+H)?(\\d+M)?(\\d+S)?)?\$"))) {
+    if (!isParseableISO8601String(interval)) {
         throw UnparsableISO8601StringException()
     }
 }
 
+
+fun isParseableISO8601String(interval: String) = interval
+    .matches(Regex("^P(?!\$)(\\d+Y)?(\\d+M)?(\\d+W)?(\\d+D)?(T(?=\\d)(\\d+H)?(\\d+M)?(\\d+S)?)?\$"))
+
+
 //TODO: consider replacing with jakarta bean validation annotations instead of throwing exception
 fun checkIfDurationIsBiggerThanOneMinute(interval: String) {
     if (interval.startsWith("PT") && Duration.parseIsoString(interval) < Duration.parseIsoString("PT1M")) {

src/test/kotlin/org/heigit/ohsome/now/statsservice/stats/StatsControllerMVCTests.kt

@@ -83,6 +83,24 @@ class StatsControllerMVCTests {
             .andExpect(content().string(expectedErrorMessage))
     }
 
+    @ParameterizedTest
+    @ValueSource(
+        strings = [
+            "/stats/missingmaps/interval?interval=bad_interval"
+        ]
+    )
+    fun `all requests with bad ISO interval throw error`(url: String) {
+
+        val expectedErrorMessage = """[{"message":"Invalid ISO8601 string as interval.","invalidValue":"bad_interval"}]"""
+
+        val GET = get(url)
+
+        this.mockMvc
+            .perform(GET)
+            .andExpect(status().isBadRequest)
+            .andExpect(content().string(expectedErrorMessage))
+    }
+
 
     @Test
     fun `stats can be served without explicit timespans`() {