updates examples

Author: KirillKurdyukov

examples/EntityFrameworkCore.Ydb.Samples/AddEntity.Sample/Program.cs

@@ -1,6 +1,4 @@
-// See https://aka.ms/new-console-template for more information
-
-using Section_1.HR;
+using Section_1.HR;
 
 InsertDepartments();
 SelectDepartments();

examples/Ydb.Sdk.AdoNet.Dapper.QuickStart/Program.cs

@@ -1,5 +1,3 @@
-// See https://aka.ms/new-console-template for more information
-
 using Dapper;
 using Ydb.Sdk.Ado;
 

examples/Ydb.Sdk.AdoNet.Yandex.Cloud.Serverless.Container/Program.cs

@@ -1,6 +1,4 @@
-// See https://aka.ms/new-console-template for more information
-
-using System.Diagnostics;
+using System.Diagnostics;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 using Ydb.Sdk.Ado;

examples/Ydb.Sdk.AdoNet.Yandex.Cloud.Serverless.Container/README.md

@@ -0,0 +1,44 @@
+# YDB Sdk ADO.NET for Serverless Containers in Yandex Cloud
+
+Sample application uses the YDB SDK for ADO.NET and can be deployed
+to [Yandex Cloud Serverless Containers](https://yandex.cloud/en/docs/serverless-containers/).
+
+## Getting started
+
+1. **Setup
+   ** [Yandex Container Registry](https://yandex.cloud/en/docs/container-registry/operations/registry/registry-create).
+2. **Build and Push Docker Image**
+   ```bash 
+   docker build . -t cr.yandex/<container-registry-id>/ado-net-app:latest
+   docker push cr.yandex/<container-registry-id>/ado-net-app:latest
+   ```
+   Replace <container-registry-id> with your actual Container Registry ID.
+3. **Grant Required Permissions**. To enable your Serverless Container to access both YDB and your container image in
+   the Container Registry, grant the following roles to your Service Account:
+
+    - `ydb.editor` — access to YDB,
+    - `container-registry.images.puller` — permission to pull images from Container Registry.
+
+4. **Create a new revision**. After pushing your image, create a new version of the Serverless Container as described in
+   the [official guide](https://yandex.cloud/en/docs/serverless-containers/quickstart/container#create-revision).
+   Specify your image and the necessary environment variables and secrets.
+5. **Running the Yandex Serverless Container**.
+   After the new revision has been rolled out, you can use your container (e.g., for a health check) by executing the following command:
+   ```bash
+   curl --header "Authorization: Bearer $(yc iam create-token)" https://<serverless-container-host>/
+   ```
+   Replace <serverless-container-host> with your actual serverless container host.
+
+## ⚠️ Important Note: YdbDataSource and Connection Handling
+
+When using the YDB SDK in a serverless container, it is always necessary to create a new YdbDataSource for each request
+or function invocation.
+
+This is because the network connectivity between a serverless container and external resources, such as YDB, can be
+interrupted or reset during execution. If you cache or reuse existing connections, you may experience failures due to
+stale or invalid connections.
+
+Best practice:
+
+_Create a fresh data source (or Driver for Topic API) for every request or function invocation in order to ensure
+reliability in the serverless environment._

examples/Ydb.Sdk.QueryService.QuickStart/Program.cs

@@ -20,8 +20,6 @@ internal class CmdOptions
     public bool FallbackAnonymous { get; set; } = false;
 }
 
-// See https://aka.ms/new-console-template for more information
-
 internal static class Program
 {
     private static ServiceProvider GetServiceProvider() =>