Add initial JSON patch prototype

sdk/core/Azure.Core.Experimental/src/JsonPatchDocument.cs

@@ -0,0 +1,80 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System.Collections.ObjectModel;
+using System.IO;
+using System.Text;
+using System.Text.Json;
+
+#pragma warning disable 1591
+
+namespace Azure.Core.JsonPatch
+{
+    public class JsonPatchDocument
+    {
+        public JsonPatchDocument()
+        {
+            Operations = new Collection<JsonPatchOperation>();
+        }
+
+        public Collection<JsonPatchOperation> Operations { get; }
+
+        public void AppendAdd(string path, string rawJsonValue)
+        {
+            Operations.Add(new JsonPatchOperation(JsonPatchOperationKind.Add, path, null,rawJsonValue));
+        }
+
+        public void AppendCopy(string from, string path, string rawJsonValue)
+        {
+            Operations.Add(new JsonPatchOperation(JsonPatchOperationKind.Copy, path, from, rawJsonValue));
+        }
+
+        public void AppendMove(string from, string path, string rawJsonValue)
+        {
+            Operations.Add(new JsonPatchOperation(JsonPatchOperationKind.Move, path, from, rawJsonValue));
+        }
+
+        public void AppendRemove(string path)
+        {
+            Operations.Add(new JsonPatchOperation(JsonPatchOperationKind.Remove, path, null, null));
+        }
+
+        public void AppendTest(string path, string rawJsonValue)
+        {
+            Operations.Add(new JsonPatchOperation(JsonPatchOperationKind.Test, path, null, rawJsonValue));
+        }
+
+        public override string ToString()
+        {
+            using var memoryStream = new MemoryStream();
+            using (var writer = new Utf8JsonWriter(memoryStream))
+            {
+                WriteTo(writer);
+            }
+            return Encoding.UTF8.GetString(memoryStream.ToArray());
+        }
+
+        internal void WriteTo(Utf8JsonWriter writer)
+        {
+            writer.WriteStartArray();
+            foreach (var operation in Operations)
+            {
+                writer.WriteStartObject();
+                writer.WriteString("op", operation.Kind.ToString());
+                writer.WriteString("path", operation.Path);
+                if (operation.From != null)
+                {
+                    writer.WriteString("path", operation.From);
+                }
+                if (operation.RawJsonValue != null)
+                {
+                    using var parsedValue = JsonDocument.Parse(operation.RawJsonValue);
+                    writer.WritePropertyName("value");
+                    parsedValue.WriteTo(writer);
+                }
+                writer.WriteEndObject();
+            }
+            writer.WriteEndArray();
+        }
+    }
+}

sdk/core/Azure.Core.Experimental/src/JsonPatchOperation.cs

@@ -0,0 +1,25 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System.Text.Json;
+
+#pragma warning disable 1591
+
+namespace Azure.Core.JsonPatch
+{
+    public class JsonPatchOperation
+    {
+        public JsonPatchOperation(JsonPatchOperationKind kind, string path, string? from, string? rawJsonValue)
+        {
+            Kind = kind;
+            Path = path;
+            From = from;
+            RawJsonValue = rawJsonValue;
+        }
+
+        public JsonPatchOperationKind Kind { get; }
+        public string Path { get; }
+        public string? From { get; }
+        public string? RawJsonValue { get; }
+    }
+}

sdk/core/Azure.Core.Experimental/src/JsonPatchOperationKind.cs

@@ -0,0 +1,21 @@
+#pragma warning disable 1591
+
+namespace Azure.Core.JsonPatch
+{
+    public readonly struct JsonPatchOperationKind
+    {
+        private readonly string _operation;
+
+        public JsonPatchOperationKind(string operation)
+        {
+            _operation = operation;
+        }
+
+        public static JsonPatchOperationKind Add { get; } = new JsonPatchOperationKind("add");
+        public static JsonPatchOperationKind Remove { get; } = new JsonPatchOperationKind("remove");
+        public static JsonPatchOperationKind Replace { get; } = new JsonPatchOperationKind("replace");
+        public static JsonPatchOperationKind Move { get; } = new JsonPatchOperationKind("move");
+        public static JsonPatchOperationKind Copy { get; } = new JsonPatchOperationKind("copy");
+        public static JsonPatchOperationKind Test { get; } = new JsonPatchOperationKind("test");
+    }
+}