Merge pull request #2120 from amulyavarote/feature/configAPI_docs

Documentation of configuration API for python sdk

daprdocs/content/en/developing-applications/building-blocks/configuration/howto-manage-configuration.md

@@ -11,6 +11,12 @@ This HowTo uses the Redis configuration store component as an example on how to
 
 *This API is currently in `Alpha` state and only available on gRPC. An HTTP1.1 supported version with this URL syntax `/v1.0/configuration` will be available before the API is certified into `Stable` state.*
 
+## Example:
+
+The below code examples loosely describe an application that processes orders. In the examples, there is an order processing service which has a Dapr sidecar. The order processing service uses Dapr to retrieve the configuration from a Redis configuration store.
+
+<img src="/images/building-block-configuration-example.png" width=1000 alt="Diagram showing get configuration of example service">
+
 ## Step 1: Create a configuration item in store
 
 First, create a configuration item in a supported configuration store. This can be a simple key-value item, with any key of your choice. For this example, we'll use the Redis configuration store component.
@@ -31,7 +37,7 @@ redis-cli -p 6379
 Save a configuration item:
 
 ```
-set myconfig "wookie"
+MSET orderId1 "101||1" orderId2 "102||1"
 ```
 
 ### Configure a Dapr configuration store
@@ -42,7 +48,7 @@ Save the following component file, for example to the [default components folder
 apiVersion: dapr.io/v1alpha1
 kind: Component
 metadata:
-  name: redisconfigstore
+  name: configstore
 spec:
   type: configuration.redis
   metadata:
@@ -52,37 +58,100 @@ spec:
     value: <PASSWORD>
 ```
 
-### Get configuration items using gRPC API
+### Get configuration items using Dapr SDKs
 
-Using your [favorite language](https://grpc.io/docs/languages/), create a Dapr gRPC client from the [Dapr proto](https://github.com/dapr/dapr/blob/master/dapr/proto/runtime/v1/dapr.proto). The following examples show Java, C#, Python and Javascript clients.
-
-{{< tabs Java Dotnet Python Javascript >}}
+{{< tabs Dotnet Java Python>}}
 
 {{% codetab %}}
-```java
+```csharp
+//dependencies
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Dapr.Client;
 
-Dapr.ServiceBlockingStub stub = Dapr.newBlockingStub(channel);
-stub.GetConfigurationAlpha1(new GetConfigurationRequest{ StoreName = "redisconfigstore", Keys = new String[]{"myconfig"} });
+//code
+namespace ConfigurationApi
+{
+    public class Program
+    {
+        private static readonly string CONFIG_STORE_NAME = "configstore";
+
+        [Obsolete]
+        public static async Task Main(string[] args)
+        {
+            using var client = new DaprClientBuilder().Build();
+            var configuration = await client.GetConfiguration(CONFIG_STORE_NAME, new List<string>() { "orderId1", "orderId2" });
+            Console.WriteLine($"Got key=\n{configuration[0].Key} -> {configuration[0].Value}\n{configuration[1].Key} -> {configuration[1].Value}");
+        }
+    }
+}
+```
+
+Navigate to the directory containing the above code and run the following command to launch the application along with a Dapr sidecar:
+
+```bash
+dapr run --app-id orderprocessing --components-path ./components -- dotnet run
 ```
 {{% /codetab %}}
 
 {{% codetab %}}
-```csharp
+```java
+//dependencies
+import io.dapr.client.DaprClientBuilder;
+import io.dapr.client.DaprPreviewClient;
+import io.dapr.client.domain.ConfigurationItem;
+import io.dapr.client.domain.GetConfigurationRequest;
+import io.dapr.client.domain.SubscribeConfigurationRequest;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
-var call = client.GetConfigurationAlpha1(new GetConfigurationRequest { StoreName = "redisconfigstore", Keys = new String[]{"myconfig"} });
+//code
+private static final String CONFIG_STORE_NAME = "configstore";
+
+public static void main(String[] args) throws Exception {
+    try (DaprPreviewClient client = (new DaprClientBuilder()).buildPreviewClient()) {
+      List<String> keys = new ArrayList<>();
+      keys.add("orderId1");
+      keys.add("orderId2");
+      GetConfigurationRequest req = new GetConfigurationRequest(CONFIG_STORE_NAME, keys);
+      try {
+        Mono<List<ConfigurationItem>> items = client.getConfiguration(req);
+        items.block().forEach(ConfigurationClient::print);
+      } catch (Exception ex) {
+        System.out.println(ex.getMessage());
+      }
+    }
+}
+```
+
+Navigate to the directory containing the above code and run the following command to launch the application along with a Dapr sidecar:
+
+```bash
+dapr run --app-id orderprocessing --components-path ./components mvn spring-boot:run
 ```
 {{% /codetab %}}
 
 {{% codetab %}}
 ```python
-response = stub.GetConfigurationAlpha1(request={ StoreName: 'redisconfigstore', Keys = ['myconfig'] })
+#dependencies
+from dapr.clients import DaprClient
+#code
+with DaprClient() as d:
+        CONFIG_STORE_NAME = 'configstore'
+        keys = ['orderId1', 'orderId2']
+        #Startup time for dapr
+        d.wait(20)
+        configuration = d.get_configuration(store_name=CONFIG_STORE_NAME, keys=[keys], config_metadata={})
+        print(f"Got key={configuration.items[0].key} value={configuration.items[0].value} version={configuration.items[0].version}")
 ```
-{{% /codetab %}}
 
-{{% codetab %}}
-```javascript
-client.GetConfigurationAlpha1({ StoreName: 'redisconfigstore', Keys = ['myconfig'] })
+Navigate to the directory containing the above code and run the following command to launch the application along with a Dapr sidecar:
+
+```bash
+dapr run --app-id orderprocessing --components-path ./components python3 OrderProcessingService.py
 ```
+
 {{% /codetab %}}
 
 {{< /tabs >}}
@@ -127,4 +196,4 @@ message UnSubscribeConfigurationRequest {
 Using this unsubscribe method, you can stop watching configuration update events. Dapr locates the subscription stream based on the `store_name` and any optional keys supplied and closes it.
 
 ## Next steps
-* Read [configuration API overview]({{< ref configuration-api-overview.md >}})
+* Read [configuration API overview]({{< ref configuration-api-overview.md >}})