Replace [Obsolete] with [Experimental] attributes (#1564)

* Replaced Obsolete with Experimental attributes throughout solution, added documentation and updated unit tests

Signed-off-by: Whit Waldo <[email protected]>

Author: WhitWaldo

daprdocs/content/en/dotnet-sdk-docs/dotnet-development/dotnet-development-experimental-attributes.md

@@ -0,0 +1,138 @@
+---
+type: docs
+title: "Dapr .NET SDK Development with Dapr CLI"
+linkTitle: "Experimental Attributes"
+weight: 61000
+description: Learn about local development with the Dapr CLI
+---
+
+## Experimental Attributes
+
+### Introduction to Experimental Attributes
+
+With the release of .NET 8, C# 12 introduced the `[Experimental]` attribute, which provides a standardized way to mark 
+APIs that are still in development or experimental. This attribute is defined in the `System.Diagnostics.CodeAnalysis` 
+namespace and requires a diagnostic ID parameter used to generate compiler warnings when the experimental API 
+is used.
+
+In the Dapr .NET SDK, we now use the `[Experimental]` attribute instead of `[Obsolete]` to mark building blocks and 
+components that have not yet passed the stable lifecycle certification. This approach provides a clearer distinction 
+between:
+
+1. **Experimental APIs** - Features that are available but still evolving and have not yet been certified as stable 
+according to the [Dapr Component Certification Lifecycle](https://docs.dapr.io/operations/components/certification-lifecycle/).
+
+2. **Obsolete APIs** - Features that are truly deprecated and will be removed in a future release.
+
+### Usage in the Dapr .NET SDK
+
+In the Dapr .NET SDK, we apply the `[Experimental]` attribute at the class level for building blocks that are still in 
+the Alpha or Beta stages of the [Component Certification Lifecycle](https://docs.dapr.io/operations/components/certification-lifecycle/). 
+The attribute includes:
+
+- A diagnostic ID that identifies the experimental building block
+- A URL that points to the relevant documentation for that block
+
+For example:
+
+```csharp
+using System.Diagnostics.CodeAnalysis;
+namespace Dapr.Cryptography.Encryption 
+{ 
+    [Experimental("DAPR_CRYPTOGRAPHY", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/cryptography/cryptography-overview/")] 
+    public class DaprEncryptionClient 
+    { 
+        // Implementation 
+    } 
+}
+```
+
+The diagnostic IDs follow a naming convention of `DAPR_[BUILDING_BLOCK_NAME]`, such as:
+
+- `DAPR_CONVERSATION` - For the Conversation building block
+- `DAPR_CRYPTOGRAPHY` - For the Cryptography building block
+- `DAPR_JOBS` - For the Jobs building block
+- `DAPR_DISTRIBUTEDLOCK` - For the Distributed Lock building block
+
+### Suppressing Experimental Warnings
+
+When you use APIs marked with the `[Experimental]` attribute, the compiler will generate errors. 
+To build your solution without marking your own code as experimental, you will need to suppress these errors. Here are 
+several approaches to do this:
+
+#### Option 1: Using #pragma directive
+
+You can use the `#pragma warning` directive to suppress the warning for specific sections of code:
+
+```csharp
+// Disable experimental warning 
+#pragma warning disable DAPR_CRYPTOGRAPHY 
+// Your code using the experimental API 
+var client = new DaprEncryptionClient(); 
+// Re-enable the warning 
+#pragma warning restore DAPR_CRYPTOGRAPHY
+```
+
+This approach is useful when you want to suppress warnings only for specific sections of your code.
+
+#### Option 2: Project-level suppression
+
+To suppress warnings for an entire project, add the following to your `.csproj` file.
+file.
+
+```xml
+<PropertyGroup>
+    <NoWarn>$(NoWarn);DAPR_CRYPTOGRAPHY</NoWarn>
+</PropertyGroup>
+```
+
+You can include multiple diagnostic IDs separated by semicolons:
+
+```xml
+<PropertyGroup>
+    <NoWarn>$(NoWarn);DAPR_CONVERSATION;DAPR_JOBS;DAPR_DISTRIBUTEDLOCK;DAPR_CRYPTOGRAPHY</NoWarn>
+</PropertyGroup>
+```
+
+This approach is particularly useful for test projects that need to use experimental APIs.
+
+#### Option 3: Directory-level suppression
+
+For suppressing warnings across multiple projects in a directory, add a `Directory.Build.props` file:
+
+```xml
+<PropertyGroup>
+    <NoWarn>$(NoWarn);DAPR_CONVERSATION;DAPR_JOBS;DAPR_DISTRIBUTEDLOCK;DAPR_CRYPTOGRAPHY</NoWarn>
+</PropertyGroup>
+```
+
+This file should be placed in the root directory of your test projects. You can learn more about using 
+`Directory.Build.props` files in the 
+[MSBuild documentation](https://learn.microsoft.com/en-us/visualstudio/msbuild/customize-by-directory).
+
+### Lifecycle of Experimental APIs
+
+As building blocks move through the certification lifecycle and reach the "Stable" stage, the `[Experimental]` attribute will be removed. No migration or code changes will be required from users when this happens, except for the removal of any warning suppressions if they were added.
+
+Conversely, the `[Obsolete]` attribute will now be reserved exclusively for APIs that are truly deprecated and scheduled for removal. When you see a method or class marked with `[Obsolete]`, you should plan to migrate away from it according to the migration guidance provided in the attribute message.
+
+### Best Practices
+
+1. **In application code:**
+    - Be cautious when using experimental APIs, as they may change in future releases
+    - Consider isolating usage of experimental APIs to make future updates easier
+    - Document your use of experimental APIs for team awareness
+
+2. **In test code:**
+    - Use project-level suppression to avoid cluttering test code with warning suppressions
+    - Regularly review which experimental APIs you're using and check if they've been stabilized
+
+3. **When contributing to the SDK:**
+    - Use `[Experimental]` for new building blocks that haven't completed certification
+    - Use `[Obsolete]` only for truly deprecated APIs
+    - Provide clear documentation links in the `UrlFormat` parameter
+
+### Additional Resources
+
+- [Dapr Component Certification Lifecycle](https://docs.dapr.io/operations/components/certification-lifecycle/)
+- [C# Experimental Attribute Documentation](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-12.0/experimental-attribute)

examples/Client/DistributedLock/Controllers/BindingController.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Text.Json;
 using System.Threading.Tasks;
@@ -11,24 +12,15 @@
 namespace DistributedLock.Controllers;
 
 [ApiController]
-public class BindingController : ControllerBase
+[Experimental("DAPR_DISTRIBUTEDLOCK", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/distributed-lock/distributed-lock-api-overview/")]
+public class BindingController(DaprClient client, ILogger<BindingController> logger) : ControllerBase
 {
-    private DaprClient client;
-    private ILogger<BindingController> logger;
-    private string appId;
-
-    public BindingController(DaprClient client, ILogger<BindingController> logger)
-    {
-        this.client = client;
-        this.logger = logger;
-        this.appId = Environment.GetEnvironmentVariable("APP_ID");
-    }
-
+    private string appId = Environment.GetEnvironmentVariable("APP_ID");
+    
     [HttpPost("cronbinding")]
-    [Obsolete]
     public async Task<IActionResult> HandleBindingEvent()
     {
-        logger.LogInformation($"Received binding event on {appId}, scanning for work.");
+        logger.LogInformation("Received binding event on {appId}, scanning for work.", appId);
 
         var request = new BindingRequest("localstorage", "list");
         var result = client.InvokeBindingAsync(request);
@@ -47,44 +39,40 @@ public async Task<IActionResult> HandleBindingEvent()
         return Ok();
     }
 
-
-    [Obsolete]
     private async Task AttemptToProcessFile(string fileName)
     {
         // Locks are Disposable and will automatically unlock at the end of a 'using' statement.
-        logger.LogInformation($"Attempting to lock: {fileName}");
-        await using (var fileLock = await client.Lock("redislock", fileName, appId, 60))
+        logger.LogInformation("Attempting to lock: {fileName}", fileName);
+        await using var fileLock = await client.Lock("redislock", fileName, appId, 60);
+        if (fileLock.Success)
         {
-            if (fileLock.Success)
-            {
-                logger.LogInformation($"Successfully locked file: {fileName}");
+            logger.LogInformation("Successfully locked file: {fileName}", fileName);
 
-                // Get the file after we've locked it, we're safe here because of the lock.
-                var fileState = await GetFile(fileName);
+            // Get the file after we've locked it, we're safe here because of the lock.
+            var fileState = await GetFile(fileName);
 
-                if (fileState == null)
-                {
-                    logger.LogWarning($"File {fileName} has already been processed!");
-                    return;
-                }
+            if (fileState == null)
+            {
+                logger.LogWarning("File {fileName} has already been processed!", fileName);
+                return;
+            }
 
-                // "Analyze" the file before committing it to our remote storage.
-                fileState.Analysis = fileState.Number > 50 ? "High" : "Low";
+            // "Analyze" the file before committing it to our remote storage.
+            fileState.Analysis = fileState.Number > 50 ? "High" : "Low";
 
-                // Save it to remote storage.
-                await client.SaveStateAsync("redisstore", fileName, fileState);
+            // Save it to remote storage.
+            await client.SaveStateAsync("redisstore", fileName, fileState);
 
-                // Remove it from local storage.
-                var bindingDeleteRequest = new BindingRequest("localstorage", "delete");
-                bindingDeleteRequest.Metadata["fileName"] = fileName;
-                await client.InvokeBindingAsync(bindingDeleteRequest);
+            // Remove it from local storage.
+            var bindingDeleteRequest = new BindingRequest("localstorage", "delete");
+            bindingDeleteRequest.Metadata["fileName"] = fileName;
+            await client.InvokeBindingAsync(bindingDeleteRequest);
 
-                logger.LogInformation($"Done processing {fileName}");
-            }
-            else
-            {
-                logger.LogWarning($"Failed to lock {fileName}.");
-            }
+            logger.LogInformation("Done processing {fileName}", fileName);
+        }
+        else
+        {
+            logger.LogWarning("Failed to lock {fileName}.", fileName);
         }
     }
 
@@ -103,4 +91,4 @@ private async Task<StateData> GetFile(string fileName)
             return null;
         }            
     }
-}
+}

examples/Directory.Build.props

@@ -7,5 +7,6 @@
     <OutputPath>$(RepoRoot)bin\$(Configuration)\examples\$(MSBuildProjectName)\</OutputPath>
 
     <IsPackable>false</IsPackable>
+    <NoWarn>$(NoWarn);DAPR_CONVERSATION;DAPR_JOBS;DAPR_DISTRIBUTEDLOCK;DAPR_CRYPTOGRAPHY</NoWarn>
   </PropertyGroup>
 </Project>

src/Dapr.AI/Conversation/DaprConversationClient.cs

@@ -11,6 +11,7 @@
 // limitations under the License.
 // ------------------------------------------------------------------------
 
+using System.Diagnostics.CodeAnalysis;
 using Autogenerated = Dapr.Client.Autogen.Grpc.v1.Dapr;
 
 namespace Dapr.AI.Conversation;
@@ -30,6 +31,7 @@ namespace Dapr.AI.Conversation;
 /// exhaustion and other problems.
 /// </para>
 /// </summary>
+[Experimental("DAPR_CONVERSATION", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
 public abstract class DaprConversationClient : DaprAIClient
 {
     /// <summary>

src/Dapr.AI/Conversation/DaprConversationClientBuilder.cs

@@ -11,6 +11,7 @@
 // limitations under the License.
 // ------------------------------------------------------------------------
 
+using System.Diagnostics.CodeAnalysis;
 using Dapr.Common;
 using Microsoft.Extensions.Configuration;
 using Autogenerated = Dapr.Client.Autogen.Grpc.v1.Dapr;
@@ -21,6 +22,7 @@ namespace Dapr.AI.Conversation;
 /// Used to create a new instance of a <see cref="DaprConversationClient"/>.
 /// </summary>
 /// <param name="configuration">An optional <see cref="IConfiguration"/> to configure the client with.</param>
+[Experimental("DAPR_CONVERSATION", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
 public sealed class DaprConversationClientBuilder(IConfiguration? configuration = null) : DaprGenericClientBuilder<DaprConversationClient>(configuration)
 {
     /// <summary>
@@ -30,6 +32,7 @@ public sealed class DaprConversationClientBuilder(IConfiguration? configuration
     /// <summary>
     /// Builds the client instance from the properties of the builder.
     /// </summary>
+    [Experimental("DAPR_CONVERSATION", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
     public override DaprConversationClient Build()
     {
         var daprClientDependencies = BuildDaprClientDependencies(typeof(DaprConversationClient).Assembly);

src/Dapr.AI/Conversation/DaprConversationGrpcClient.cs

@@ -11,6 +11,7 @@
 //  limitations under the License.
 //  ------------------------------------------------------------------------
 
+using System.Diagnostics.CodeAnalysis;
 using Dapr.Common;
 using Dapr.Common.Extensions;
 using Autogenerated = Dapr.Client.Autogen.Grpc.v1;
@@ -23,6 +24,7 @@ namespace Dapr.AI.Conversation;
 /// <param name="client">The Dapr client.</param>
 /// <param name="httpClient">The HTTP client used by the client for calling the Dapr runtime.</param>
 /// <param name="daprApiToken">An optional token required to send requests to the Dapr sidecar.</param>
+[Experimental("DAPR_CONVERSATION", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
 internal sealed class DaprConversationGrpcClient(Autogenerated.Dapr.DaprClient client, HttpClient httpClient, string? daprApiToken = null) : DaprConversationClient(client, httpClient, daprApiToken: daprApiToken)
 { 
     /// <summary>

src/Dapr.AI/Conversation/Extensions/DaprAiConversationBuilderExtensions.cs

@@ -11,6 +11,7 @@
 // limitations under the License.
 // ------------------------------------------------------------------------
 
+using System.Diagnostics.CodeAnalysis;
 using Dapr.Common.Extensions;
 using Microsoft.Extensions.DependencyInjection;
 
@@ -24,6 +25,7 @@ public static class DaprAiConversationBuilderExtensions
     /// <summary>
     /// Registers the necessary functionality for the Dapr AI Conversation functionality.
     /// </summary>
+    [Experimental("DAPR_CONVERSATION", UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
     public static IDaprAiConversationBuilder AddDaprConversationClient(
         this IServiceCollection services,
         Action<IServiceProvider, DaprConversationClientBuilder>? configure = null,