feat(format): support duration

Author: kylef

Sources/Draft201909Validator.swift

@@ -61,6 +61,7 @@ public class Draft201909Validator: Validator {
     "uuid": validateUUID,
     "regex": validateRegex,
     "json-pointer": validateJSONPointer,
+    "duration": validateDuration,
   ]
 
   public required init(schema: Bool) {

Sources/Draft202012Validator.swift

@@ -62,6 +62,7 @@ public class Draft202012Validator: Validator {
     "uuid": validateUUID,
     "regex": validateRegex,
     "json-pointer": validateJSONPointer,
+    "duration": validateDuration,
   ]
 
   public required init(schema: Bool) {

Sources/Format/duration.swift

@@ -0,0 +1,54 @@
+import Foundation
+
+/*
+https://tools.ietf.org/html/rfc3339
+
+Durations:
+
+   dur-second        = 1*DIGIT "S"
+   dur-minute        = 1*DIGIT "M" [dur-second]
+   dur-hour          = 1*DIGIT "H" [dur-minute]
+   dur-time          = "T" (dur-hour / dur-minute / dur-second)
+   dur-day           = 1*DIGIT "D"
+   dur-week          = 1*DIGIT "W"
+   dur-month         = 1*DIGIT "M" [dur-day]
+   dur-year          = 1*DIGIT "Y" [dur-month]
+   dur-date          = (dur-day / dur-month / dur-year) [dur-time]
+
+   duration          = "P" (dur-date / dur-time / dur-week)
+*/
+var durationExpression: NSRegularExpression = {
+  let second = "(\\d+S)"
+  let minute = "((\\d+M)\(second)?)"
+  let hour = "((\\d+H)\(minute)?)"
+  let time = "(T(\(hour)|\(minute)|\(second)))"
+
+  let day = "(\\d+D)"
+  let week = "(\\d+W)"
+  let month = "((\\d+M)\(day)?)"
+  let year = "((\\d+Y)\(month)?)"
+  let date = "((\(day)|\(month)|\(year))\(time)?)"
+
+  let duration = "^P(\(date)|\(time)|\(week))$"
+  return try! NSRegularExpression(pattern: duration, options: [])
+}()
+
+
+func isValidDuration(_ value: String) -> Bool {
+  return durationExpression.numberOfMatches(in: value, range: NSMakeRange(0, value.utf16.count)) != 0
+}
+
+
+func validateDuration(_ context: Context, _ value: String) -> AnySequence<ValidationError> {
+  guard isValidDuration(value) else {
+    return AnySequence([
+      ValidationError(
+        "'\(value)' is not a valid duration.",
+        instanceLocation: context.instanceLocation,
+        keywordLocation: context.keywordLocation
+      )
+    ])
+  }
+
+  return AnySequence(EmptyCollection())
+}

Tests/JSONSchemaTests/Format/TestDuration.swift

@@ -0,0 +1,77 @@
+import XCTest
+@testable import JSONSchema
+
+
+class DurationTests: XCTestCase {
+  // dur-date
+
+  func testDay() {
+    XCTAssertTrue(isValidDuration("P3D"))
+  }
+
+  func testMonth() {
+    XCTAssertTrue(isValidDuration("P2M"))
+  }
+
+  func testMonthDay() {
+    XCTAssertTrue(isValidDuration("P2M1D"))
+  }
+
+  func testYear() {
+    XCTAssertTrue(isValidDuration("P5Y"))
+  }
+
+  func testYearMonth() {
+    XCTAssertTrue(isValidDuration("P5Y2M"))
+  }
+
+  func testYearMonthDay() {
+    XCTAssertTrue(isValidDuration("P5Y2M1D"))
+  }
+
+  func testDateTime() {
+    XCTAssertTrue(isValidDuration("P1DT5M"))
+  }
+
+  // dur-time
+
+  func testHour() {
+    XCTAssertTrue(isValidDuration("PT1H"))
+  }
+
+  func testHourMinute() {
+    XCTAssertTrue(isValidDuration("PT1H5M"))
+  }
+
+  func testHourMinuteSecond() {
+    XCTAssertTrue(isValidDuration("PT1H5M20S"))
+  }
+
+  func testMinute() {
+    XCTAssertTrue(isValidDuration("PT1M"))
+  }
+
+  func testMinuteSecond() {
+    XCTAssertTrue(isValidDuration("PT5M10S"))
+  }
+
+  func testSecond() {
+    XCTAssertTrue(isValidDuration("PT1S"))
+  }
+
+  // dur-week
+
+  func testWeek() {
+    XCTAssertTrue(isValidDuration("P1W"))
+  }
+
+  // Negative
+
+  func testMissingDuration() {
+    XCTAssertFalse(isValidDuration("P"))
+  }
+
+  func testMissingTime() {
+    XCTAssertFalse(isValidDuration("PT"))
+  }
+}

Tests/JSONSchemaTests/JSONSchemaCases.swift

@@ -175,7 +175,6 @@ class JSONSchemaCases: XCTestCase {
       "format.json",
       "date-time.json",
       "date.json",
-      "duration.json",
       "email.json",
       "hostname.json",
       "idn-email.json",
@@ -211,7 +210,6 @@ class JSONSchemaCases: XCTestCase {
       "format.json",
       "date-time.json",
       "date.json",
-      "duration.json",
       "email.json",
       "hostname.json",
       "idn-email.json",