azcore fix: POST responses can be any type (#3721)

Fixes #3716. In the autorest client, POST responses were unmarshaled
into `any`, which allows for primitive types as well as objects. In the
new azcore client, they were unmarshaled into `map[string]any`,
requiring the response to be an object.

examples/cs-getcustomdomainverificationid/Program.cs

@@ -0,0 +1,12 @@
+using System.Collections.Generic;
+using Pulumi.AzureNative.App;
+
+return await Pulumi.Deployment.RunAsync(() =>
+{
+    var azureDomainVerificationId = GetCustomDomainVerificationId.Invoke().Apply(x => x.Value);
+
+    return new Dictionary<string, object?>
+    {
+        ["domainVerificationId"] = azureDomainVerificationId
+    };
+});

examples/cs-getcustomdomainverificationid/Pulumi.yaml

@@ -0,0 +1,7 @@
+name: cs-getcustomdomainverificationid
+description: An Azure Native C# Pulumi program calling the App.GetCustomDomainVerificationId invoke
+runtime: dotnet
+config:
+  pulumi:tags:
+    value:
+      pulumi:template: azure-csharp

examples/cs-getcustomdomainverificationid/azn-3716-azcore.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Pulumi" Version="3.*" />
+    <PackageReference Include="Pulumi.AzureNative" Version="2.*" />
+  </ItemGroup>
+
+</Project>

examples/examples_dotnet_test.go

@@ -51,6 +51,15 @@ func TestPortalDashboardDotnet(t *testing.T) {
 	integration.ProgramTest(t, &test)
 }
 
+func TestGetCustomDomainVerificationId(t *testing.T) {
+	test := getCsharpBaseOptions(t).
+		With(integration.ProgramTestOptions{
+			Dir: filepath.Join(getCwd(t), "cs-getcustomdomainverificationid"),
+		})
+
+	integration.ProgramTest(t, &test)
+}
+
 func TestPulumiExamples(t *testing.T) {
 	for _, example := range pexamples.GetTestsByTags(pexamples.AzureNativeProvider, pexamples.CS) {
 		t.Run(example.Dir, func(t *testing.T) {

provider/pkg/azure/client_azcore.go

@@ -353,8 +353,12 @@ func (c *azCoreClient) Post(ctx context.Context, id string, bodyProps map[string
 		return nil, runtime.NewResponseError(resp)
 	}
 
-	var responseBody map[string]interface{}
-	err = runtime.UnmarshalAsJSON(resp, &responseBody)
+	return readResponse(resp)
+}
+
+func readResponse(resp *http.Response) (any, error) {
+	var responseBody any
+	err := runtime.UnmarshalAsJSON(resp, &responseBody)
 	return responseBody, handleAzCoreResponseError(err, resp)
 }
 

provider/pkg/azure/client_azcore_test.go

@@ -677,3 +677,23 @@ func (errorReadCloser) Read(p []byte) (n int, err error) {
 func (errorReadCloser) Close() error {
 	return nil
 }
+
+func TestPostResponsesCanBeAnything(t *testing.T) {
+	t.Run("string", func(t *testing.T) {
+		resp := &http.Response{
+			Body: io.NopCloser(strings.NewReader(`"hello"`)),
+		}
+		val, err := readResponse(resp)
+		require.NoError(t, err)
+		assert.Equal(t, "hello", val)
+	})
+
+	t.Run("object", func(t *testing.T) {
+		resp := &http.Response{
+			Body: io.NopCloser(strings.NewReader(`{"k": 1}`)),
+		}
+		val, err := readResponse(resp)
+		require.NoError(t, err)
+		assert.Equal(t, map[string]any{"k": 1.0}, val)
+	})
+}