QueryDefinition: Adds API to get query parameters

Microsoft.Azure.Cosmos/src/Query/v3Query/QueryDefinition.cs

@@ -5,6 +5,7 @@
 namespace Microsoft.Azure.Cosmos
 {
     using System;
+    using System.Collections;
     using System.Collections.Generic;
     using Microsoft.Azure.Cosmos.Query.Core;
     using Newtonsoft.Json;
@@ -17,6 +18,8 @@ public class QueryDefinition
         [JsonProperty(PropertyName = "parameters", NullValueHandling = NullValueHandling.Ignore, Order = 1)]
         private List<SqlParameter> parameters { get; set; }
 
+        private ParametersListAdapter parametersAdapter;
+
         /// <summary>
         /// Create a <see cref="QueryDefinition"/>
         /// </summary>
@@ -105,15 +108,60 @@ public QueryDefinition WithParameter(string name, object value)
             return this;
         }
 
+        /// <summary>
+        /// Returns the names and values of parameters in this <see cref="QueryDefinition"/>.
+        /// </summary>
+        /// <returns>
+        /// A list of name/value tuples representing the parameters of this <see cref="QueryDefinition"/>.
+        /// </returns>
+        public IReadOnlyList<(string Name, object Value)> GetQueryParameters()
+        {
+            return this.parametersAdapter ??= new ParametersListAdapter(this);
+        }
+
         internal SqlQuerySpec ToSqlQuerySpec()
         {
-            return new SqlQuerySpec(this.QueryText, new SqlParameterCollection(this.parameters ?? new List<SqlParameter>()));
+            return new SqlQuerySpec(this.QueryText, new SqlParameterCollection(this.parameters ?? (IReadOnlyList<SqlParameter>)Array.Empty<SqlParameter>()));
         }
 
         /// <summary>
         /// Gets the sql parameters for the class
         /// </summary>
         [JsonIgnore]
-        internal IReadOnlyList<SqlParameter> Parameters => this.parameters ?? new List<SqlParameter>();
+        internal IReadOnlyList<SqlParameter> Parameters => this.parameters ?? (IReadOnlyList<SqlParameter>)Array.Empty<SqlParameter>();
+
+        private class ParametersListAdapter : IReadOnlyList<(string Name, object Value)>
+        {
+            private readonly QueryDefinition queryDefinition;
+
+            public ParametersListAdapter(QueryDefinition queryDefinition)
+            {
+                this.queryDefinition = queryDefinition;
+            }
+
+            public (string Name, object Value) this[int index]
+            {
+                get
+                {
+                    SqlParameter param = this.queryDefinition.Parameters[index];
+                    return (param.Name, param.Value);
+                }
+            }
+
+            public int Count => this.queryDefinition.Parameters.Count;
+
+            public IEnumerator<(string Name, object Value)> GetEnumerator()
+            {
+                foreach (SqlParameter param in this.queryDefinition.Parameters)
+                {
+                    yield return (param.Name, param.Value);
+                }
+            }
+
+            IEnumerator IEnumerable.GetEnumerator()
+            {
+                return this.GetEnumerator();
+            }
+        }
     }
 }

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/Contracts/DotNetSDKAPI.json

@@ -4426,6 +4426,11 @@
           "Attributes": [],
           "MethodInfo": "Microsoft.Azure.Cosmos.QueryDefinition WithParameter(System.String, System.Object);IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
         },
+        "System.Collections.Generic.IReadOnlyList`1[System.ValueTuple`2[System.String,System.Object]] GetQueryParameters()": {
+          "Type": "Method",
+          "Attributes": [],
+          "MethodInfo": "System.Collections.Generic.IReadOnlyList`1[System.ValueTuple`2[System.String,System.Object]] GetQueryParameters();IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
+        },
         "System.String get_QueryText()[System.Runtime.CompilerServices.CompilerGeneratedAttribute()]": {
           "Type": "Method",
           "Attributes": [

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/QueryDefinitionUnitTests.cs

@@ -5,6 +5,7 @@
 namespace Microsoft.Azure.Cosmos.Tests
 {
     using System;
+    using System.Collections.Generic;
     using System.Linq;
     using Microsoft.Azure.Cosmos.Query.Core;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
@@ -65,5 +66,93 @@ public void ThrowOnNullConnectionString()
             QueryDefinition sqlQueryDefinition = new QueryDefinition("select * from s where s.Account = 1234");
             sqlQueryDefinition.WithParameter(null, null);
         }
+
+        [TestMethod]
+        public void GetQueryParametersReturnsListOfTuples()
+        {
+            string query = "select * from s where s.Account = @account and s.Balance > @balance";
+            QueryDefinition queryDefinition = new QueryDefinition(query)
+                .WithParameter("@account", "12345")
+                .WithParameter("@balance", 42);
+
+            IReadOnlyList<(string Name, object Value)> parameters = queryDefinition.GetQueryParameters();
+
+            Assert.AreEqual(2, parameters.Count);
+            Assert.AreEqual("@account", parameters[0].Name);
+            Assert.AreEqual("12345", parameters[0].Value);
+            Assert.AreEqual("@balance", parameters[1].Name);
+            Assert.AreEqual(42, parameters[1].Value);
+        }
+
+        [TestMethod]
+        public void GetQueryParametersAlwaysReturnsTheSameInstance()
+        {
+            string query = "select * from s where s.Account = @account and s.Balance > @balance";
+            QueryDefinition queryDefinition = new QueryDefinition(query)
+                .WithParameter("@account", "12345")
+                .WithParameter("@balance", 42);
+
+            IReadOnlyList<(string Name, object Value)> parameters1 = queryDefinition.GetQueryParameters();
+            IReadOnlyList<(string Name, object Value)> parameters2 = queryDefinition.GetQueryParameters();
+
+            Assert.AreSame(parameters1, parameters2);
+        }
+
+        [TestMethod]
+        public void GetQueryParametersReflectsParametersAddedLater()
+        {
+            string query = "select * from s where s.Account = @account and s.Balance > @balance";
+            QueryDefinition queryDefinition = new QueryDefinition(query)
+                .WithParameter("@account", "12345");
+
+            IReadOnlyList<(string Name, object Value)> parameters = queryDefinition.GetQueryParameters();
+
+            queryDefinition.WithParameter("@balance", 42);
+
+            Assert.AreEqual(2, parameters.Count);
+            Assert.AreEqual("@account", parameters[0].Name);
+            Assert.AreEqual("12345", parameters[0].Value);
+            Assert.AreEqual("@balance", parameters[1].Name);
+            Assert.AreEqual(42, parameters[1].Value);
+        }
+
+        [TestMethod]
+        public void GetQueryParametersReflectsParametersChangedLater()
+        {
+            string query = "select * from s where s.Account = @account and s.Balance > @balance";
+            QueryDefinition queryDefinition = new QueryDefinition(query)
+                .WithParameter("@account", "12345")
+                .WithParameter("@balance", 42);
+
+            IReadOnlyList<(string Name, object Value)> parameters = queryDefinition.GetQueryParameters();
+
+            queryDefinition.WithParameter("@balance", 123);
+
+            Assert.AreEqual(2, parameters.Count);
+            Assert.AreEqual("@account", parameters[0].Name);
+            Assert.AreEqual("12345", parameters[0].Value);
+            Assert.AreEqual("@balance", parameters[1].Name);
+            Assert.AreEqual(123, parameters[1].Value);
+        }
+
+        [TestMethod]
+        public void GetQueryParametersGetEnumeratorEnumeratesParameters()
+        {
+            string query = "select * from s where s.Account = @account and s.Balance > @balance";
+            QueryDefinition queryDefinition = new QueryDefinition(query)
+                .WithParameter("@account", "12345")
+                .WithParameter("@balance", 42);
+
+            IReadOnlyList<(string Name, object Value)> parameters = queryDefinition.GetQueryParameters();
+            IEnumerator<(string Name, object Value)> enumerator = parameters.GetEnumerator();
+
+            Assert.IsTrue(enumerator.MoveNext());
+            Assert.AreEqual("@account", enumerator.Current.Name);
+            Assert.AreEqual("12345", enumerator.Current.Value);
+            Assert.IsTrue(enumerator.MoveNext());
+            Assert.AreEqual("@balance", enumerator.Current.Name);
+            Assert.AreEqual(42, enumerator.Current.Value);
+            Assert.IsFalse(enumerator.MoveNext());
+        }
     }
 }

changelog.md

@@ -3,6 +3,9 @@ Preview features are treated as a separate branch and will not be included in th
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+- [#2191](https://github.com/Azure/azure-cosmos-dotnet-v3/issues/2191) & [#796](https://github.com/Azure/azure-cosmos-dotnet-v3/issues/796) Query: Expose query parameters
+
 ### <a name="3.16.0"/> [3.16.0](https://www.nuget.org/packages/Microsoft.Azure.Cosmos/3.16.0) - 2021-01-12
 
 #### Added