Support string next link (Azure#50766)

* Support string next link

* regen

* Fix merge

* Fix visitor bug

* fix

* test

* Add test

Author: JoshLove-msft

eng/packages/http-client-csharp/generator/Azure.Generator/src/Providers/CollectionResultDefinition.cs

@@ -49,6 +49,7 @@ internal class CollectionResultDefinition : TypeProvider
             new("pageSizeHint", $"The number of items per page.", new CSharpType(typeof(int?)));
 
         private readonly bool _isProtocol;
+        private readonly PropertyProvider? _nextPageProperty;
 
         public CollectionResultDefinition(ClientProvider client, InputPagingServiceMethod serviceMethod, CSharpType? itemModelType, bool isAsync)
         {
@@ -116,9 +117,9 @@ public CollectionResultDefinition(ClientProvider client, InputPagingServiceMetho
             // Use the canonical view in case the property was customized.
             if (_nextPageLocation == InputResponseLocation.Body)
             {
-                _nextPagePropertyName =
-                    responseModel.CanonicalView.Properties.FirstOrDefault(
-                        p => p.WireInfo?.SerializedName == nextPagePropertyName)?.Name;
+                _nextPageProperty = responseModel.CanonicalView.Properties.FirstOrDefault(
+                    p => p.WireInfo?.SerializedName == nextPagePropertyName);
+                _nextPagePropertyName = _nextPageProperty?.Name;
             }
             else if (_nextPageLocation == InputResponseLocation.Header)
             {
@@ -202,15 +203,15 @@ private MethodBodyStatement[] BuildAsPagesMethodBody()
                 doWhileStatement.Add(ConvertItemsToListOfBinaryData(responseWithTypeVariable, out var itemsVariable));
 
                 // Extract next page
-                doWhileStatement.Add(nextPageVariable.Assign(_nextPagePropertyName is null ? Null : BuildGetNextPage(responseWithTypeVariable, responseVariable)).Terminate());
+                doWhileStatement.Add(nextPageVariable.Assign(BuildGetNextPage(responseWithTypeVariable, responseVariable)).Terminate());
 
                 // Create and yield the page
                 doWhileStatement.Add(YieldReturn(Static(new CSharpType(typeof(Page<>), [_itemModelType])).Invoke("FromValues", [itemsVariable, nextPageExpression, responseVariable])));
             }
             else
             {
                 // Extract next page
-                doWhileStatement.Add(nextPageVariable.Assign(_nextPagePropertyName is null ? Null : BuildGetNextPage(responseWithTypeVariable, responseVariable)).Terminate());
+                doWhileStatement.Add(nextPageVariable.Assign(BuildGetNextPage(responseWithTypeVariable, responseVariable)).Terminate());
 
                 // Create and yield the page
                 doWhileStatement.Add(YieldReturn(Static(new CSharpType(typeof(Page<>), [_itemModelType])).Invoke("FromValues", [responseWithTypeVariable.Property(_itemsPropertyName).CastTo(new CSharpType(typeof(IReadOnlyList<>), _itemModelType)), nextPageExpression, responseVariable])));
@@ -263,18 +264,37 @@ private ValueExpression BuildGetNextPage(VariableExpression responseWithTypeVari
                 return Null;
             }
 
-            switch (_nextPageLocation)
+            return _nextPageLocation switch
             {
-                case InputResponseLocation.Body:
-                    return responseWithTypeVariable.Property(_nextPagePropertyName);
-                case InputResponseLocation.Header:
-                    return new TernaryConditionalExpression(
-                        responseVariable.Property("Headers").Invoke("TryGetValue", Literal(_nextPagePropertyName), new DeclarationExpression(typeof(string), "value", out var nextLinkHeader, isOut: true)).As<bool>(),
-                        nextLinkHeader,
-                        Null);
-                default:
-                    // Invalid location is logged by the emitter.
-                    return Null;
+                InputResponseLocation.Body =>NeedsConversionToUri() ? New.Instance<Uri>(responseWithTypeVariable.Property(_nextPagePropertyName)) : responseWithTypeVariable.Property(_nextPagePropertyName),
+                InputResponseLocation.Header => new TernaryConditionalExpression(
+                    responseVariable.Property("Headers")
+                        .Invoke("TryGetValue", Literal(_nextPagePropertyName),
+                            new DeclarationExpression(typeof(string), "value", out var nextLinkHeader, isOut: true))
+                        .As<bool>(),
+                     NeedsConversionToUri() ? New.Instance<Uri>(nextLinkHeader) : nextLinkHeader,
+                    Null),
+                _ => Null
+            };
+
+            bool NeedsConversionToUri()
+            {
+                if (_paging.NextLink == null)
+                {
+                    return false;
+                }
+                if (_nextPageLocation == InputResponseLocation.Body &&
+                    _nextPageProperty?.Type.Equals(typeof(string)) == true)
+                {
+                    return true;
+                }
+
+                if (_nextPageLocation == InputResponseLocation.Header)
+                {
+                    return true;
+                }
+
+                return false;
             }
         }
 

eng/packages/http-client-csharp/generator/Azure.Generator/src/Visitors/SpecialHeadersVisitor.cs

@@ -20,24 +20,29 @@ namespace Azure.Generator.Visitors
     /// </summary>
     internal class SpecialHeadersVisitor : ScmLibraryVisitor
     {
+        private const string ClientRequestIdParameterName = "client-request-id";
+        private const string ReturnClientRequestIdParameterName = "return-client-request-id";
+        private const string XMsClientRequestIdParameterName = "x-ms-client-request-id";
         protected override ScmMethodProviderCollection? Visit(
             InputServiceMethod serviceMethod,
             ClientProvider client,
             ScmMethodProviderCollection? methods)
         {
             var clientRequestIdParameter =
-                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == "client-request-id");
+                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == ClientRequestIdParameterName);
             var returnClientRequestIdParameter =
-                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == "return-client-request-id");
+                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == ReturnClientRequestIdParameterName);
             var xMsClientRequestIdParameter =
-                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == "x-ms-client-request-id");
+                serviceMethod.Parameters.FirstOrDefault(p => p.NameInRequest == XMsClientRequestIdParameterName);
 
             if (clientRequestIdParameter != null || returnClientRequestIdParameter != null || xMsClientRequestIdParameter != null)
             {
                 serviceMethod.Update(parameters: serviceMethod.Parameters
-                    .Where(p => p != clientRequestIdParameter && p != returnClientRequestIdParameter && p != xMsClientRequestIdParameter)
+                    .Where(p => p.NameInRequest != ClientRequestIdParameterName && p.NameInRequest != ReturnClientRequestIdParameterName && p.NameInRequest != XMsClientRequestIdParameterName)
+                    .ToList());
+                serviceMethod.Operation.Update(parameters: serviceMethod.Operation.Parameters
+                    .Where(p => p.NameInRequest != ClientRequestIdParameterName && p.NameInRequest != ReturnClientRequestIdParameterName && p.NameInRequest != XMsClientRequestIdParameterName)
                     .ToList());
-                serviceMethod.Operation.Update(parameters: serviceMethod.Parameters);
 
                 // Create a new method collection with the updated service method
                 methods = new ScmMethodProviderCollection(serviceMethod, client);

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/NextLinkTests.cs

@@ -154,6 +154,34 @@ public void NextLinkInBodyMultipleClients()
             Assert.IsNotNull(felineClientCollectionResult);
         }
 
+        [Test]
+        public void NextLinkInBodyOfTWithStringProperty()
+        {
+            CreatePagingOperation(InputResponseLocation.Body, useStringProperty: true);
+
+            var collectionResultDefinition = AzureClientGenerator.Instance.OutputLibrary.TypeProviders.FirstOrDefault(
+                t => t is CollectionResultDefinition && t.Name == "CatClientGetCatsCollectionResultOfT");
+            Assert.IsNotNull(collectionResultDefinition);
+
+            var writer = new TypeProviderWriter(collectionResultDefinition!);
+            var file = writer.Write();
+            Assert.AreEqual(Helpers.GetExpectedFromFile(), file.Content);
+        }
+
+        [Test]
+        public void NextLinkInBodyWithStringProperty()
+        {
+            CreatePagingOperation(InputResponseLocation.Body, useStringProperty: true);
+
+            var collectionResultDefinition = AzureClientGenerator.Instance.OutputLibrary.TypeProviders.FirstOrDefault(
+                t => t is CollectionResultDefinition && t.Name == "CatClientGetCatsCollectionResult");
+            Assert.IsNotNull(collectionResultDefinition);
+
+            var writer = new TypeProviderWriter(collectionResultDefinition!);
+            var file = writer.Write();
+            Assert.AreEqual(Helpers.GetExpectedFromFile(), file.Content);
+        }
+
         [Test]
         public void UsesValidFieldIdentifierNames()
         {
@@ -190,7 +218,7 @@ public void UsesValidFieldIdentifierNames()
             Assert.IsTrue(fields.Any(f => f.Name == "_foo"));
         }
 
-        private static void CreatePagingOperation(InputResponseLocation responseLocation)
+        private static void CreatePagingOperation(InputResponseLocation responseLocation, bool useStringProperty = false)
         {
             var inputModel = InputFactory.Model("cat", properties:
             [
@@ -201,7 +229,10 @@ private static void CreatePagingOperation(InputResponseLocation responseLocation
                 [200],
                 InputFactory.Model(
                     "page",
-                    properties: [InputFactory.Property("cats", InputFactory.Array(inputModel)), InputFactory.Property("nextCat", InputPrimitiveType.Url)]));
+                    properties: [
+                        InputFactory.Property("cats", InputFactory.Array(inputModel)),
+                        InputFactory.Property("nextCat", useStringProperty ? InputPrimitiveType.String : InputPrimitiveType.Url)
+                    ]));
             var operation = InputFactory.Operation("getCats", responses: [response]);
             var inputServiceMethod = InputFactory.PagingServiceMethod("getCats", operation, pagingMetadata: pagingMetadata);
             var client = InputFactory.Client("catClient", methods: [inputServiceMethod]);

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/TestData/NextLinkTests/NextLinkInBodyOfTWithStringProperty.cs

@@ -0,0 +1,71 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.Collections.Generic;
+using Azure;
+using Azure.Core;
+using Azure.Core.Pipeline;
+using Samples.Models;
+
+namespace Samples
+{
+    internal partial class CatClientGetCatsCollectionResultOfT : global::Azure.Pageable<global::Samples.Models.Cat>
+    {
+        private readonly global::Samples.CatClient _client;
+        private readonly global::Azure.RequestContext _context;
+
+        /// <summary> Initializes a new instance of CatClientGetCatsCollectionResultOfT, which is used to iterate over the pages of a collection. </summary>
+        /// <param name="client"> The CatClient client used to send requests. </param>
+        /// <param name="context"> The request options, which can override default behaviors of the client pipeline on a per-call basis. </param>
+        public CatClientGetCatsCollectionResultOfT(global::Samples.CatClient client, global::Azure.RequestContext context) : base((context?.CancellationToken ?? default))
+        {
+            _client = client;
+            _context = context;
+        }
+
+        /// <summary> Gets the pages of CatClientGetCatsCollectionResultOfT as an enumerable collection. </summary>
+        /// <param name="continuationToken"> A continuation token indicating where to resume paging. </param>
+        /// <param name="pageSizeHint"> The number of items per page. </param>
+        /// <returns> The pages of CatClientGetCatsCollectionResultOfT as an enumerable collection. </returns>
+        public override global::System.Collections.Generic.IEnumerable<global::Azure.Page<global::Samples.Models.Cat>> AsPages(string continuationToken, int? pageSizeHint)
+        {
+            global::System.Uri nextPage = (continuationToken != null) ? new global::System.Uri(continuationToken) : null;
+            do
+            {
+                global::Azure.Response response = this.GetNextResponse(pageSizeHint, nextPage);
+                if ((response is null))
+                {
+                    yield break;
+                }
+                global::Samples.Models.Page responseWithType = ((global::Samples.Models.Page)response);
+                nextPage = new global::System.Uri(responseWithType.NextCat);
+                yield return global::Azure.Page<global::Samples.Models.Cat>.FromValues(((global::System.Collections.Generic.IReadOnlyList<global::Samples.Models.Cat>)responseWithType.Cats), nextPage?.AbsoluteUri, response);
+            }
+            while ((nextPage != null));
+        }
+
+        /// <summary> Get next page. </summary>
+        /// <param name="pageSizeHint"> The number of items per page. </param>
+        /// <param name="nextLink"> The next link to use for the next page of results. </param>
+        private global::Azure.Response GetNextResponse(int? pageSizeHint, global::System.Uri nextLink)
+        {
+            global::Azure.Core.HttpMessage message = (nextLink != null) ? _client.CreateNextGetCatsRequest(nextLink, _context) : _client.CreateGetCatsRequest(_context);
+            using global::Azure.Core.Pipeline.DiagnosticScope scope = _client.ClientDiagnostics.CreateScope("CatClient.GetCats");
+            scope.Start();
+            try
+            {
+                return _client.Pipeline.ProcessMessage(message, _context);
+            }
+            catch (global::System.Exception e)
+            {
+                scope.Failed(e);
+                throw;
+            }
+        }
+    }
+}

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/TestData/NextLinkTests/NextLinkInBodyWithStringProperty.cs

@@ -0,0 +1,76 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.Collections.Generic;
+using Azure;
+using Azure.Core;
+using Azure.Core.Pipeline;
+using Samples.Models;
+
+namespace Samples
+{
+    internal partial class CatClientGetCatsCollectionResult : global::Azure.Pageable<global::System.BinaryData>
+    {
+        private readonly global::Samples.CatClient _client;
+        private readonly global::Azure.RequestContext _context;
+
+        /// <summary> Initializes a new instance of CatClientGetCatsCollectionResult, which is used to iterate over the pages of a collection. </summary>
+        /// <param name="client"> The CatClient client used to send requests. </param>
+        /// <param name="context"> The request options, which can override default behaviors of the client pipeline on a per-call basis. </param>
+        public CatClientGetCatsCollectionResult(global::Samples.CatClient client, global::Azure.RequestContext context) : base((context?.CancellationToken ?? default))
+        {
+            _client = client;
+            _context = context;
+        }
+
+        /// <summary> Gets the pages of CatClientGetCatsCollectionResult as an enumerable collection. </summary>
+        /// <param name="continuationToken"> A continuation token indicating where to resume paging. </param>
+        /// <param name="pageSizeHint"> The number of items per page. </param>
+        /// <returns> The pages of CatClientGetCatsCollectionResult as an enumerable collection. </returns>
+        public override global::System.Collections.Generic.IEnumerable<global::Azure.Page<global::System.BinaryData>> AsPages(string continuationToken, int? pageSizeHint)
+        {
+            global::System.Uri nextPage = (continuationToken != null) ? new global::System.Uri(continuationToken) : null;
+            do
+            {
+                global::Azure.Response response = this.GetNextResponse(pageSizeHint, nextPage);
+                if ((response is null))
+                {
+                    yield break;
+                }
+                global::Samples.Models.Page responseWithType = ((global::Samples.Models.Page)response);
+                global::System.Collections.Generic.List<global::System.BinaryData> items = new global::System.Collections.Generic.List<global::System.BinaryData>();
+                foreach (var item in responseWithType.Cats)
+                {
+                    items.Add(global::System.BinaryData.FromObjectAsJson(item));
+                }
+                nextPage = new global::System.Uri(responseWithType.NextCat);
+                yield return global::Azure.Page<global::System.BinaryData>.FromValues(items, nextPage?.AbsoluteUri, response);
+            }
+            while ((nextPage != null));
+        }
+
+        /// <summary> Get next page. </summary>
+        /// <param name="pageSizeHint"> The number of items per page. </param>
+        /// <param name="nextLink"> The next link to use for the next page of results. </param>
+        private global::Azure.Response GetNextResponse(int? pageSizeHint, global::System.Uri nextLink)
+        {
+            global::Azure.Core.HttpMessage message = (nextLink != null) ? _client.CreateNextGetCatsRequest(nextLink, _context) : _client.CreateGetCatsRequest(_context);
+            using global::Azure.Core.Pipeline.DiagnosticScope scope = _client.ClientDiagnostics.CreateScope("CatClient.GetCats");
+            scope.Start();
+            try
+            {
+                return _client.Pipeline.ProcessMessage(message, _context);
+            }
+            catch (global::System.Exception e)
+            {
+                scope.Failed(e);
+                throw;
+            }
+        }
+    }
+}

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/TestData/NextLinkTests/NextLinkInHeader.cs

@@ -48,7 +48,7 @@ public CatClientGetCatsCollectionResult(global::Samples.CatClient client, global
                 {
                     items.Add(global::System.BinaryData.FromObjectAsJson(item));
                 }
-                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? value : null;
+                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? new global::System.Uri(value) : null;
                 yield return global::Azure.Page<global::System.BinaryData>.FromValues(items, nextPage?.AbsoluteUri, response);
             }
             while ((nextPage != null));

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/TestData/NextLinkTests/NextLinkInHeaderAsync.cs

@@ -49,7 +49,7 @@ public CatClientGetCatsAsyncCollectionResult(global::Samples.CatClient client, g
                 {
                     items.Add(global::System.BinaryData.FromObjectAsJson(item));
                 }
-                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? value : null;
+                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? new global::System.Uri(value) : null;
                 yield return global::Azure.Page<global::System.BinaryData>.FromValues(items, nextPage?.AbsoluteUri, response);
             }
             while ((nextPage != null));

eng/packages/http-client-csharp/generator/Azure.Generator/test/Providers/CollectionResultDefinitions/TestData/NextLinkTests/NextLinkInHeaderOfT.cs

@@ -43,7 +43,7 @@ public CatClientGetCatsCollectionResultOfT(global::Samples.CatClient client, glo
                     yield break;
                 }
                 global::Samples.Models.Page responseWithType = ((global::Samples.Models.Page)response);
-                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? value : null;
+                nextPage = response.Headers.TryGetValue("nextCat", out string value) ? new global::System.Uri(value) : null;
                 yield return global::Azure.Page<global::Samples.Models.Cat>.FromValues(((global::System.Collections.Generic.IReadOnlyList<global::Samples.Models.Cat>)responseWithType.Cats), nextPage?.AbsoluteUri, response);
             }
             while ((nextPage != null));