feat: add a generic API request interface

EasyPost.Tests/ClientTest.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Net;
 using System.Net.Http;
 using System.Threading;
@@ -7,8 +8,8 @@
 using EasyPost.Exceptions.API;
 using EasyPost.Tests._Utilities;
 using EasyPost.Tests._Utilities.Attributes;
+using Newtonsoft.Json.Linq;
 using Xunit;
-using CustomAssertions = EasyPost.Tests._Utilities.Assertions.Assert;
 
 namespace EasyPost.Tests
 {
@@ -301,5 +302,24 @@ public async Task TestCancellationToken()
             // this will not record a cassette because the request should be cancelled before it is sent
             await Assert.ThrowsAsync<TimeoutError>(async () => await Client.Address.Create(new Parameters.Address.Create(), token));
         }
+
+        [Fact]
+        [Testing.Function]
+        public async Task TestClientMakeApiCall()
+        {
+            UseVCR("make_api_call");
+
+            Dictionary<string, object> parameters = new()
+            {
+                { "page_size", 1 },
+            };
+
+            Dictionary<string, object> response = await Client.MakeApiCallAsync(Http.Method.Get, "/addresses", parameters);
+
+            JArray addresses = response["addresses"] as JArray;
+            Assert.Single(addresses);
+            JObject firstAddress = addresses[0] as JObject;
+            Assert.Equal("Address", firstAddress["object"].ToString());
+        }
     }
 }

EasyPost/_base/EasyPostClient.cs

@@ -181,6 +181,22 @@ public async Task<bool> RequestAsync(Method method, string endpoint, ApiVersion
             return errorRaised;
         }
 
+        /// <summary>
+        ///     Make an API call to the EasyPost API.
+        ///     This public, generic interface is useful for making arbitrary API calls to the EasyPost API that
+        ///     are not yet supported by the client library's services. When possible, the service for your use case
+        ///     should be used instead as it provides a more convenient and higher-level interface depending on the endpoint.
+        /// </summary>
+        /// <param name="method">HTTP <see cref="Method"/> to use for the request.</param>
+        /// <param name="endpoint">EasyPost API endpoint to use for the request.</param>
+        /// <param name="parameters">Parameters to use for the request.</param>
+        /// <param name="cancellationToken"><see cref="CancellationToken"/> to use for the HTTP request.</param>
+        /// <returns>A <see cref="Dictionary{TKey, TValue}"/> representing the response data.</returns>
+        public async Task<Dictionary<string, object>> MakeApiCallAsync(Method method, string endpoint, Dictionary<string, object> parameters, CancellationToken cancellationToken = default)
+        {
+            return await RequestAsync<Dictionary<string, object>>(method, endpoint, ApiVersion.Current, cancellationToken, parameters);
+        }
+
         /// <summary>
         ///     Compare this <see cref="EasyPostClient"/> to another object for equality.
         /// </summary>