[Docs] Add README.md (how to run) for Chat Sample

samples/ChatSample/ChatSample/Dockerfile

@@ -2,24 +2,24 @@
 # Build stage
 ##################################################
 
-FROM mcr.microsoft.com/dotnet/core/sdk:8.0
+FROM mcr.microsoft.com/dotnet/sdk:8.0
 
 COPY ./ /home/signalr-src
 
 WORKDIR /home/signalr-src/samples/ChatSample/ChatSample 
 RUN dotnet build && \
-    dotnet publish -r ubuntu.16.04-x64 -c Release -o /home/build/
+    dotnet publish -r linux-x64 -c Release -o /home/build/
 
 ##################################################
 # Final stage
 ##################################################
 
-FROM mcr.microsoft.com/dotnet/core/runtime:8.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 COPY --from=0 /home/build/ /home/SignalR
 
 WORKDIR /home/SignalR
 
 EXPOSE 5050
 
-CMD ["./ChatSample"]
+CMD ["./ChatSample", "--urls", "http://0.0.0.0:5050"]

samples/ChatSample/ChatSample/README.md

@@ -0,0 +1,80 @@
+# Azure SignalR Service Chat Sample
+
+This sample demonstrates how to use Azure SignalR Service with ASP.NET Core SignalR.
+
+## Prerequisites
+
+- .NET 8.0 SDK or later
+- An Azure SignalR Service instance
+- Git (for submodule dependencies)
+- Docker (optional, for containerized deployment)
+
+## Setup
+
+1. Initialize the required submodules:
+
+```bash
+git submodule update --init --recursive
+```
+
+2. Configure your Azure SignalR Service connection string:
+
+   - Update `appsettings.json` by replacing the empty connection string:
+
+    ```json
+    {
+      "Azure": {
+        "SignalR": {
+          "ConnectionString": "<your-connection-string>"
+        }
+      }
+    }
+    ```
+
+   ⚠️ **Important**: Make sure to set your connection string before building the Docker image or running the application.
+
+## Running the Sample
+
+### Option 1: Running Locally
+
+1. Build and run the project:
+
+```bash
+dotnet build
+dotnet run
+```
+
+You can also specify a custom port:
+
+```bash
+dotnet run --urls="http://localhost:5050"
+```
+
+### Option 2: Running with Docker
+
+1. Build the Docker image:
+```bash
+docker build -t chat-app -f samples/ChatSample/ChatSample/Dockerfile .
+```
+
+2. Run the container:
+```bash
+docker run -d -p 5050:5050 chat-app
+```
+
+Additional Docker commands:
+```bash
+# View running containers
+docker ps
+
+# View container logs
+docker logs <container_id>
+
+# Stop the container
+docker stop <container_id>
+```
+
+## Accessing the Application
+
+To access the chat application, open your web browser and navigate to:
+- `http://localhost:5050` (or the custom port you specified)