Support collection of model-type bindings for out-of-proc workers (#8948)

* Collection support changes

Author: surgupta-msft

src/WebJobs.Script.Grpc/MessageExtensions/GrpcMessageConversionExtensions.cs

@@ -56,6 +56,7 @@ public static ValueTask<TypedData> ToRpc(this object value, ILogger logger, Grpc
                     string str => new TypedData() { String = str },
                     double dbl => new TypedData() { Double = dbl },
                     ParameterBindingData bindingData => bindingData.ToModelBindingData(),
+                    ParameterBindingData[] bindingDataArray => bindingDataArray.ToModelBindingDataArray(),
                     byte[][] arrBytes when IsTypedDataCollectionSupported(capabilities) => arrBytes.ToRpcByteArray(),
                     string[] arrStr when IsTypedDataCollectionSupported(capabilities) => arrStr.ToRpcStringArray(
                                                             ShouldIncludeEmptyEntriesInMessagePayload(capabilities)),
@@ -84,6 +85,21 @@ internal static TypedData ToModelBindingData(this ParameterBindingData data)
             return typedData;
         }
 
+        internal static TypedData ToModelBindingDataArray(this ParameterBindingData[] dataArray)
+        {
+            var collectionModelBindingData = new CollectionModelBindingData();
+
+            foreach (ParameterBindingData element in dataArray)
+            {
+                if (element != null)
+                {
+                    collectionModelBindingData.ModelBindingData.Add(element.ToModelBindingData().ModelBindingData);
+                }
+            }
+
+            return new TypedData() { CollectionModelBindingData = collectionModelBindingData };
+        }
+
         internal static async Task<TypedData> ToRpcHttp(this HttpRequest request, ILogger logger, GrpcCapabilities capabilities)
         {
             var http = new RpcHttp()

src/WebJobs.Script/Binding/ExtensionBinding.cs

@@ -111,6 +111,10 @@ public override async Task BindAsync(BindingContext context)
             {
                 await BindStringAsync(context);
             }
+            else if (_binding.DefaultType == typeof(ParameterBindingData[]))
+            {
+                await BindCollectionAsync<ParameterBindingData>(context);
+            }
             else if (_binding.DefaultType == typeof(ParameterBindingData))
             {
                 await BindParameterBindingDataAsync(context);

src/WebJobs.Script/Binding/FunctionBinding.cs

@@ -7,6 +7,7 @@
 using System.Collections.ObjectModel;
 using System.Dynamic;
 using System.IO;
+using System.Linq;
 using System.Reflection.Emit;
 using System.Text;
 using System.Threading.Tasks;
@@ -221,6 +222,12 @@ internal static async Task BindStringAsync(BindingContext context)
             context.Value = str;
         }
 
+        internal static async Task BindCollectionAsync<T>(BindingContext context)
+        {
+            T[] bindingList = await context.Binder.BindAsync<T[]>(context.Attributes);
+            context.Value = bindingList;
+        }
+
         internal static async Task BindParameterBindingDataAsync(BindingContext context)
         {
             var parameterBindingData = await context.Binder.BindAsync<ParameterBindingData>(context.Attributes);

test/WebJobs.Script.Tests/Workers/Rpc/GrpcMessageConversionExtensionsTests.cs

@@ -711,5 +711,54 @@ public void ToModelBindingData_Creates_Valid_BindingData()
 
             Assert.Equal(typedData.ModelBindingData, returned_typedata.ModelBindingData);
         }
+
+        [Fact]
+        public void ToModelBindingDataArray_Creates_Valid_BindingData()
+        {
+            var logger = MockNullLoggerFactory.CreateLogger();
+            var capabilities = new GrpcCapabilities(logger);
+
+            var binaryData = new BinaryData("hello world");
+            var parameterBindingData = new ParameterBindingData("1.0", "CosmosDB", binaryData, "application/json");
+            var parameterBindingDataArray = new ParameterBindingData[] { parameterBindingData, parameterBindingData };
+
+            TypedData returned_typedData = parameterBindingDataArray.ToModelBindingDataArray();
+
+            var modelBindingData = new ModelBindingData
+            {
+                Version = parameterBindingData.Version,
+                ContentType = parameterBindingData.ContentType,
+                Source = parameterBindingData.Source,
+                Content = ByteString.CopyFrom(parameterBindingData.Content)
+            };
+
+            var collectionModelBindingData = new CollectionModelBindingData();
+            collectionModelBindingData.ModelBindingData.Add(modelBindingData);
+            collectionModelBindingData.ModelBindingData.Add(modelBindingData);
+
+            TypedData typedData = new TypedData();
+            typedData.CollectionModelBindingData = collectionModelBindingData;
+
+            Assert.Equal(2, returned_typedData.CollectionModelBindingData.ModelBindingData.Count);
+            Assert.Equal(typedData.CollectionModelBindingData.ModelBindingData.First(), returned_typedData.CollectionModelBindingData.ModelBindingData.First());
+        }
+
+        [Fact]
+        public void ToModelBindingData_EmptyAndNullArray_Creates_Valid_BindingData()
+        {
+            var parameterBindingDataEmptyArray = new ParameterBindingData[] { };
+            var parameterBindingDataNullArray = new ParameterBindingData[] { null };
+
+            TypedData returned_emptyTypedData = parameterBindingDataEmptyArray.ToModelBindingDataArray();
+            TypedData returned_nullTypedData = parameterBindingDataNullArray.ToModelBindingDataArray();
+
+            var collectionModelBindingData = new CollectionModelBindingData();
+
+            TypedData typedData = new TypedData();
+            typedData.CollectionModelBindingData = collectionModelBindingData;
+
+            Assert.Equal(0, returned_emptyTypedData.CollectionModelBindingData.ModelBindingData.Count);
+            Assert.Equal(0, returned_nullTypedData.CollectionModelBindingData.ModelBindingData.Count);
+        }
     }
 }