Adding null check to fix the issue with input/output binding for the sdk type scenario (#9139)

* Bug fix by adding null check when no expression

Author: surgupta-msft

src/WebJobs.Script/Description/Workers/WorkerFunctionDescriptorProvider.cs

@@ -129,11 +129,16 @@ internal bool BindingAttributeContainsExpression(IEnumerable<FunctionBinding> bi
                 {
                     return attribute.GetType()
                                     .GetProperties(BindingFlags.Instance | BindingFlags.Public)
-                                    .Any(prop => prop.PropertyType == typeof(string) && _expressionRegex.IsMatch((string)prop.GetValue(attribute)));
+                                    .Any(prop => prop.PropertyType == typeof(string) && IsMatch((string)prop.GetValue(attribute)));
                 }
             }
 
             return false;
         }
+
+        private bool IsMatch(string value)
+        {
+            return string.IsNullOrEmpty(value) ? false : _expressionRegex.IsMatch(value);
+        }
     }
 }

test/WebJobs.Script.Tests/Description/Worker/WorkerFunctionDescriptorProviderTests.cs

@@ -84,6 +84,39 @@ public void BindingAttributeContainsExpression__InputBinding_FindsRegexMatch_Ret
             Assert.True(result);
         }
 
+        [Fact]
+        public void BindingAttributeContainsExpression__InputBinding_EmptyConnection_FindsRegexMatch_ReturnsTrue()
+        {
+            var inputBindingJObject = JObject.Parse("{\"name\":\"myBlob\",\"direction\":\"In\",\"type\":\"blob\",\"blobPath\":\"input-container//{id}.txt\",\"connection\":\"\",\"properties\":{\"supportsDeferredBinding\":true}}");
+            FunctionBinding inputBinding = TestHelpers.CreateBindingFromHost(_host, inputBindingJObject);
+            IEnumerable<FunctionBinding> bindings = new List<FunctionBinding>() { inputBinding };
+
+            bool result = _provider.BindingAttributeContainsExpression(bindings);
+            Assert.True(result);
+        }
+
+        [Fact]
+        public void BindingAttributeContainsExpression__InputBinding_EmptyConnection_NoRegex_FindsRegexMatch_ReturnsFalse()
+        {
+            var inputBindingJObject = JObject.Parse("{\"name\":\"myBlob\",\"direction\":\"In\",\"type\":\"blob\",\"blobPath\":\"input-container//file.txt\",\"connection\":\"\",\"properties\":{\"supportsDeferredBinding\":true}}");
+            FunctionBinding inputBinding = TestHelpers.CreateBindingFromHost(_host, inputBindingJObject);
+            IEnumerable<FunctionBinding> bindings = new List<FunctionBinding>() { inputBinding };
+
+            bool result = _provider.BindingAttributeContainsExpression(bindings);
+            Assert.False(result);
+        }
+
+        [Fact]
+        public void BindingAttributeContainsExpression__InputBinding_EmptyFields_FindsRegexMatch_ReturnsFalse()
+        {
+            var inputBindingJObject = JObject.Parse("{\"name\":\"myBlob\",\"direction\":\"In\",\"type\":\"blob\",\"blobPath\":\"\",\"connection\":\"\",\"properties\":{\"supportsDeferredBinding\":true}}");
+            FunctionBinding inputBinding = TestHelpers.CreateBindingFromHost(_host, inputBindingJObject);
+            IEnumerable<FunctionBinding> bindings = new List<FunctionBinding>() { inputBinding };
+
+            bool result = _provider.BindingAttributeContainsExpression(bindings);
+            Assert.False(result);
+        }
+
         [Fact]
         public void BindingAttributeContainsExpression_OutputBinding_FindsRegexMatch_ReturnsTrue()
         {
@@ -95,6 +128,28 @@ public void BindingAttributeContainsExpression_OutputBinding_FindsRegexMatch_Ret
             Assert.True(result);
         }
 
+        [Fact]
+        public void BindingAttributeContainsExpression_OutputBinding_EmptyConnection_FindsRegexMatch_ReturnsTrue()
+        {
+            var outputBindingJObject = JObject.Parse("{\"name\":\"$return\",\"direction\":\"Out\",\"type\":\"blob\",\"blobPath\":\"output-container//{name}-output.txt\",\"connection\":\"\",\"properties\":{}}");
+            FunctionBinding outputBinding = TestHelpers.CreateBindingFromHost(_host, outputBindingJObject);
+            IEnumerable<FunctionBinding> bindings = new List<FunctionBinding>() { outputBinding };
+
+            bool result = _provider.BindingAttributeContainsExpression(bindings);
+            Assert.True(result);
+        }
+
+        [Fact]
+        public void BindingAttributeContainsExpression_OutputBinding_EmptyFields_FindsRegexMatch_ReturnsFalse()
+        {
+            var outputBindingJObject = JObject.Parse("{\"name\":\"$return\",\"direction\":\"Out\",\"type\":\"blob\",\"blobPath\":\"\",\"connection\":\"\",\"properties\":{}}");
+            FunctionBinding outputBinding = TestHelpers.CreateBindingFromHost(_host, outputBindingJObject);
+            IEnumerable<FunctionBinding> bindings = new List<FunctionBinding>() { outputBinding };
+
+            bool result = _provider.BindingAttributeContainsExpression(bindings);
+            Assert.False(result);
+        }
+
         [Fact]
         public void BindingAttributeContainsExpression_DoesNotFindRegexMatch_ReturnsFalse()
         {