From a543a402ec8985d83cee925fd9beef2d6bf42521 Mon Sep 17 00:00:00 2001 From: Jiro Kugiya Date: Sun, 22 Jul 2018 17:44:57 +0900 Subject: [PATCH] Supports snakecase. --- .../spray/json/SnakeCaseJsonSupport.scala | 52 ++++++++ .../spray/json/SnakeCaseJsonSupportSpec.scala | 113 ++++++++++++++++++ 2 files changed, 165 insertions(+) create mode 100644 src/main/scala/spray/json/SnakeCaseJsonSupport.scala create mode 100644 src/test/scala/spray/json/SnakeCaseJsonSupportSpec.scala diff --git a/src/main/scala/spray/json/SnakeCaseJsonSupport.scala b/src/main/scala/spray/json/SnakeCaseJsonSupport.scala new file mode 100644 index 00000000..07ef776e --- /dev/null +++ b/src/main/scala/spray/json/SnakeCaseJsonSupport.scala @@ -0,0 +1,52 @@ +package spray.json + +import scala.reflect.ClassTag +import scala.collection.mutable + +/** + * Provides snake cased JsonFormats + */ +trait SnakeCaseJsonSupport extends DefaultJsonProtocol { + + override protected def extractFieldNames(classTag: ClassTag[_]): Array[String] = { + def snakify(name: String) = { + val chars = name.toCharArray + val len = name.length + val sb = new mutable.StringBuilder(len + len / 5) + + def isAlphabetic(char: Char): Boolean = (char >= 'a' && char <= 'z') || (char >= 'A' && char <= 'Z') + + def go(i: Int, rest: Int, processedUpper: Boolean, processedAlphaNumeric: Boolean): String = + if (rest == 0) { + sb.toString() + } else if (rest > 1 && chars(i).isUpper && chars(i + 1).isLower) { + if (processedAlphaNumeric) { + sb.append('_') + } + sb.append(chars(i).toLower).append(chars(i + 1)) + go(i + 2, rest - 2, false, true) + } else if (chars(i).isUpper) { + if (!processedUpper && processedAlphaNumeric) { + sb.append('_') + } + sb.append(chars(i).toLower) + go(i + 1, rest - 1, true, chars(i).isDigit || isAlphabetic(chars(i))) + } else if (!isAlphabetic(chars(i))) { + sb.append(chars(i)) + go(i + 1, rest - 1, false, chars(i).isDigit) + } else { + sb.append(chars(i).toLower) + go(i + 1, rest - 1, chars(i).isUpper, chars(i).isDigit || isAlphabetic(chars(i))) + } + + go(0, len, true, false) + } + + super.extractFieldNames(classTag).map { + snakify(_) + } + } + +} + +object SnakeCaseJsonSupport extends SnakeCaseJsonSupport diff --git a/src/test/scala/spray/json/SnakeCaseJsonSupportSpec.scala b/src/test/scala/spray/json/SnakeCaseJsonSupportSpec.scala new file mode 100644 index 00000000..1abeb993 --- /dev/null +++ b/src/test/scala/spray/json/SnakeCaseJsonSupportSpec.scala @@ -0,0 +1,113 @@ +package spray.json + +import java.util.Locale + +import org.specs2.mutable._ + +class SnakeCaseJsonSupportSpec extends Specification with SnakeCaseJsonSupport { + + private val PASS1 = """([A-Z]+)([A-Z][a-z])""".r + private val PASS2 = """([a-z\d])([A-Z])""".r + private val REPLACEMENT = "$1_$2" + + def snakify(name: String) = + PASS2.replaceAllIn(PASS1.replaceAllIn(name, REPLACEMENT), REPLACEMENT).toLowerCase(Locale.US) + + "SnakeCaseJsonSUpport" should { + "convert field names to snake cased fields names." in { + // Given + case class SampleFields( + HelloWorld: Int = 0, + A1AAbBBBBBbCCcc: Int = 0, + AbAAbbAAAbbb1AA2bb1AA2AAAAbb1bAA: Int = 0, + x: Int = 0, + Y: Int = 0, + `^There-arE_Non_(Alphabetic))_character!S`: Int = 0, + `tHere-Are_(AlsO)_noN_(alphaBetic))_CharaCter!s`: Int = 0, + ` There are space character `: Int = 0, + ` これは　マルチバイトAbcのaBc確認です。`: Int = 0, + aa: Int = 0, + AA: Int = 0, + Aa: Int = 0, + aA: Int = 0, + AAA: Int = 0, + AAa: Int = 0, + AaA: Int = 0, + aAA: Int = 0, + aaA: Int = 0, + aAa: Int = 0, + Aaa: Int = 0, + aaa: Int = 0 + ) + case class SampleFields2( + aaa123bbb: Int = 0, + aaA123bbb: Int = 0, + aaa123Bbb: Int = 0, + aaA123Bbb: Int = 0, + aaa123: Int = 0, + aaA123: Int = 0, + aAA123: Int = 0 + ) + implicit val jsonFormat1: RootJsonFormat[SampleFields] = + jsonFormat21(SampleFields.apply) + implicit val jsonFormat2: RootJsonFormat[SampleFields2] = + jsonFormat7(SampleFields2.apply) + // When + val sampleFields1 = SampleFields().toJson.asJsObject + val sampleFields2 = SampleFields2().toJson.asJsObject + // Then + val fields1 = sampleFields1.fields + fields1.contains(snakify("HelloWorld")) mustEqual true + fields1.contains(snakify("A1AAbBBBBBbCCcc")) mustEqual true + fields1.contains(snakify("AbAAbbAAAbbb1AA2bb1AA2AAAAbb1bAA")) mustEqual true + fields1.contains(snakify("x")) mustEqual true + fields1.contains(snakify("Y")) mustEqual true + fields1.contains(snakify("^There-arE_Non_(Alphabetic))_character!S")) mustEqual true + fields1.contains(snakify("tHere-Are_(AlsO)_noN_(alphaBetic))_CharaCter!s")) mustEqual true + fields1.contains(snakify(" There are space character ")) mustEqual true + fields1.contains(snakify(" これは　マルチバイトAbcのaBc確認です。")) mustEqual true + fields1.contains(snakify("aa")) mustEqual true + fields1.contains(snakify("aA")) mustEqual true + fields1.contains(snakify("Aa")) mustEqual true + fields1.contains(snakify("AA")) mustEqual true + fields1.contains(snakify("AAA")) mustEqual true + fields1.contains(snakify("aaA")) mustEqual true + fields1.contains(snakify("aAa")) mustEqual true + fields1.contains(snakify("Aaa")) mustEqual true + fields1.contains(snakify("AAa")) mustEqual true + fields1.contains(snakify("AaA")) mustEqual true + fields1.contains(snakify("aAA")) mustEqual true + fields1.contains(snakify("aaa")) mustEqual true + val fields2 = sampleFields2.fields + fields2.contains(snakify("aaa123bbb")) mustEqual true + fields2.contains(snakify("aaa123Bbb")) mustEqual true + fields2.contains(snakify("aaA123bbb")) mustEqual true + fields2.contains(snakify("aaa123")) mustEqual true + fields2.contains(snakify("aaA123")) mustEqual true + fields2.contains(snakify("aAA123")) mustEqual true + } + "deserialize snake cased json" in { + // Given + case class SampleFields( + a: Int, + aA: Int, + helloWorld: Int, + HelloTheWorld: Int + ) + implicit val jsonFormat: RootJsonFormat[SampleFields] = + jsonFormat4(SampleFields.apply) + val json = JsObject( + "hello_the_world" -> 4.toJson, + "a_a" -> 2.toJson, + "a" -> 1.toJson, + "hello_world" -> 3.toJson + ) + // When + val result = jsonFormat.read(json) + // Then + result mustEqual SampleFields( + a = 1, aA = 2, helloWorld = 3, HelloTheWorld = 4 + ) + } + } +}