Fix discrepancies in Watcher API models which fail (de)serialization (#5761)

* Update models to support correct deserialisation

* Update tests

* Fix tests and exceptions

Author: stevejgordon

src/Nest/XPack/Watcher/Schedule/CronExpressions.cs

@@ -0,0 +1,50 @@
+// Licensed to Elasticsearch B.V under one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using Elasticsearch.Net.Utf8Json;
+
+namespace Nest
+{
+	[InterfaceDataContract]
+	[JsonFormatter(typeof(ScheduleFormatter<ICronExpressions, CronExpressions, CronExpression>))]
+	public interface ICronExpressions : ISchedule, IEnumerable<CronExpression> { void Add(CronExpression expression); }
+
+	public class CronExpressions : ScheduleBase, ICronExpressions
+	{
+		private List<CronExpression> _expressions;
+
+		public CronExpressions(IEnumerable<CronExpression> expressions) => _expressions = expressions?.ToList();
+
+		public CronExpressions(params CronExpression[] expressions) => _expressions = expressions?.ToList();
+
+		public CronExpressions() { }
+
+		IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+
+		public IEnumerator<CronExpression> GetEnumerator() => _expressions?.GetEnumerator()
+			?? Enumerable.Empty<CronExpression>().GetEnumerator();
+
+		public void Add(CronExpression expression)
+		{
+			if (_expressions == null)
+				_expressions = new List<CronExpression>();
+			_expressions.Add(expression);
+		}
+
+		internal override void WrapInContainer(IScheduleContainer container) => container.CronExpressions = this;
+
+		public static implicit operator CronExpressions(CronExpression[] cronExpressions) => new(cronExpressions);
+	}
+
+	public class CronExpressionsDescriptor : DescriptorPromiseBase<CronExpressionsDescriptor, ICronExpressions>
+	{
+		public CronExpressionsDescriptor() : base(new CronExpressions()) { }
+
+		public CronExpressionsDescriptor Add(CronExpression cronExpression) =>	Assign(cronExpression, (a, v) => a.Add(v));
+	}
+}

src/Nest/XPack/Watcher/Schedule/DailySchedule.cs

@@ -13,10 +13,10 @@ namespace Nest
 	[ReadAs(typeof(TimeOfDay))]
 	public interface ITimeOfDay
 	{
-		[DataMember(Name ="hour")]
+		[DataMember(Name = "hour")]
 		IEnumerable<int> Hour { get; set; }
 
-		[DataMember(Name ="minute")]
+		[DataMember(Name = "minute")]
 		IEnumerable<int> Minute { get; set; }
 	}
 
@@ -44,28 +44,41 @@ public class TimeOfDayDescriptor : DescriptorBase<TimeOfDayDescriptor, ITimeOfDa
 	[ReadAs(typeof(DailySchedule))]
 	public interface IDailySchedule : ISchedule
 	{
-		[DataMember(Name ="at")]
-		Union<IEnumerable<string>, ITimeOfDay> At { get; set; }
+		[DataMember(Name = "at")]
+		Union<IEnumerable<string>, IEnumerable<ITimeOfDay>> At { get; set; }
 	}
 
 	public class DailySchedule : ScheduleBase, IDailySchedule
 	{
-		public Union<IEnumerable<string>, ITimeOfDay> At { get; set; }
+		public DailySchedule() { }
+
+		public DailySchedule(string at) => At = new[] { at };
+
+		public DailySchedule(ITimeOfDay at) => At = new[] { at };
+
+		public Union<IEnumerable<string>, IEnumerable<ITimeOfDay>> At { get; set; }
 
 		internal override void WrapInContainer(IScheduleContainer container) => container.Daily = this;
 	}
 
 	public class DailyScheduleDescriptor : DescriptorBase<DailyScheduleDescriptor, IDailySchedule>, IDailySchedule
 	{
-		Union<IEnumerable<string>, ITimeOfDay> IDailySchedule.At { get; set; }
+		Union<IEnumerable<string>, IEnumerable<ITimeOfDay>> IDailySchedule.At { get; set; }
 
 		public DailyScheduleDescriptor At(Func<TimeOfDayDescriptor, ITimeOfDay> selector) =>
-			Assign(selector, (a, v) => a.At = new Union<IEnumerable<string>, ITimeOfDay>(v?.InvokeOrDefault(new TimeOfDayDescriptor())));
+			Assign(selector,
+				(a, v) => a.At = new Union<IEnumerable<string>, IEnumerable<ITimeOfDay>>(new[] { v?.InvokeOrDefault(new TimeOfDayDescriptor()) }));
+
+		public DailyScheduleDescriptor At(IEnumerable<ITimeOfDay> times) =>
+			Assign(new Union<IEnumerable<string>, IEnumerable<ITimeOfDay>>(times), (a, v) => a.At = v);
+
+		public DailyScheduleDescriptor At(params ITimeOfDay[] times) =>
+			Assign(new Union<IEnumerable<string>, IEnumerable<ITimeOfDay>>(times), (a, v) => a.At = v);
 
 		public DailyScheduleDescriptor At(IEnumerable<string> times) =>
-			Assign(new Union<IEnumerable<string>, ITimeOfDay>(times), (a, v) => a.At = v);
+			Assign(new Union<IEnumerable<string>, IEnumerable<ITimeOfDay>>(times), (a, v) => a.At = v);
 
 		public DailyScheduleDescriptor At(params string[] times) =>
-			Assign(new Union<IEnumerable<string>, ITimeOfDay>(times), (a, v) => a.At = v);
+			Assign(new Union<IEnumerable<string>, IEnumerable<ITimeOfDay>>(times), (a, v) => a.At = v);
 	}
 }

src/Nest/XPack/Watcher/Schedule/Month.cs

@@ -5,46 +5,45 @@
 using System.Runtime.Serialization;
 using Elasticsearch.Net;
 
-
 namespace Nest
 {
 	[StringEnum]
 	public enum Month
 	{
-		[EnumMember(Value = "january")]
+		[EnumMember(Value = "JAN")]
 		January,
 
-		[EnumMember(Value = "february")]
+		[EnumMember(Value = "FEB")]
 		February,
 
-		[EnumMember(Value = "march")]
+		[EnumMember(Value = "MAR")]
 		March,
 
-		[EnumMember(Value = "april")]
+		[EnumMember(Value = "APR")]
 		April,
 
-		[EnumMember(Value = "may")]
+		[EnumMember(Value = "MAY")]
 		May,
 
-		[EnumMember(Value = "june")]
+		[EnumMember(Value = "JUN")]
 		June,
 
-		[EnumMember(Value = "july")]
+		[EnumMember(Value = "JUL")]
 		July,
 
-		[EnumMember(Value = "august")]
+		[EnumMember(Value = "AUG")]
 		August,
 
-		[EnumMember(Value = "september")]
+		[EnumMember(Value = "SEP")]
 		September,
 
-		[EnumMember(Value = "october")]
+		[EnumMember(Value = "OCT")]
 		October,
 
-		[EnumMember(Value = "november")]
+		[EnumMember(Value = "NOV")]
 		November,
 
-		[EnumMember(Value = "december")]
+		[EnumMember(Value = "DEC")]
 		December
 	}
 }