操作指南：从存储中管理配置
学习如何获取应用程序配置并订阅更改
本示例使用Redis配置存储组件来演示如何检索配置项。
注意
如果您还没有试过，请尝试配置快速入门，快速了解如何使用配置API。在存储中创建配置项
在支持的配置存储中创建一个配置项。这可以是一个简单的键值项，使用您选择的任何键。本示例使用Redis配置存储组件。
使用Docker运行Redis
docker run --name my-redis -p 6379:6379 -d redis:6 保存一个配置项
使用Redis CLI，连接到Redis实例：
redis-cli -p 6379 保存一个配置项：
MSET orderId1 "101||1" orderId2 "102||1" 配置Dapr配置存储
将以下组件文件保存到您机器上的默认组件文件夹。您可以将其用作Dapr组件YAML：
- 对于Kubernetes使用
kubectl。 - 使用Dapr CLI运行时。
注意
由于Redis配置组件与Redisstatestore.yaml组件具有相同的元数据，如果您已经有Redis statestore.yaml，可以直接复制或修改Redis状态存储组件类型。apiVersion: dapr.io/v1alpha1 kind: Component metadata: name: configstore spec: type: configuration.redis metadata: - name: redisHost value: localhost:6379 - name: redisPassword value: <PASSWORD> 检索配置项
获取配置项
以下示例展示了如何使用Dapr配置API获取已保存的配置项。
//依赖项 using System; using System.Collections.Generic; using System.Threading.Tasks; using Dapr.Client; //代码 namespace ConfigurationApi { public class Program { private static readonly string CONFIG_STORE_NAME = "configstore"; 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}"); } } } //依赖项 import io.dapr.client.DaprClientBuilder; import io.dapr.client.DaprClient; 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; //代码 private static final String CONFIG_STORE_NAME = "configstore"; public static void main(String[] args) throws Exception { try (DaprClient client = (new DaprClientBuilder()).build()) { 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()); } } } #依赖项 from dapr.clients import DaprClient #代码 with DaprClient() as d: CONFIG_STORE_NAME = 'configstore' keys = ['orderId1', 'orderId2'] #Dapr启动时间 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}") package main import ( "context" "fmt" dapr "github.com/dapr/go-sdk/client" ) func main() { ctx := context.Background() client, err := dapr.NewClient() if err != nil { panic(err) } items, err := client.GetConfigurationItems(ctx, "configstore", ["orderId1","orderId2"]) if err != nil { panic(err) } for key, item := range items { fmt.Printf("get config: key = %s value = %s version = %s",key,(*item).Value, (*item).Version) } } import { CommunicationProtocolEnum, DaprClient } from "@dapr/dapr"; // JS SDK尚不支持通过HTTP协议的配置API const protocol = CommunicationProtocolEnum.GRPC; const host = process.env.DAPR_HOST ?? "localhost"; const port = process.env.DAPR_GRPC_PORT ?? 3500; const DAPR_CONFIGURATION_STORE = "configstore"; const CONFIGURATION_ITEMS = ["orderId1", "orderId2"]; async function main() { const client = new DaprClient(host, port, protocol); // 从配置存储中获取配置项 try { const config = await client.configuration.get(DAPR_CONFIGURATION_STORE, CONFIGURATION_ITEMS); Object.keys(config.items).forEach((key) => { console.log("Configuration for " + key + ":", JSON.stringify(config.items[key])); }); } catch (error) { console.log("Could not get config item, err:" + error); process.exit(1); } } main().catch((e) => console.error(e)); 启动一个Dapr sidecar：
dapr run --app-id orderprocessing --dapr-http-port 3601 在另一个终端中，获取之前保存的配置项：
curl http://localhost:3601/v1.0/configuration/configstore?key=orderId1 启动一个Dapr sidecar：
dapr run --app-id orderprocessing --dapr-http-port 3601 在另一个终端中，获取之前保存的配置项：
Invoke-RestMethod -Uri 'http://localhost:3601/v1.0/configuration/configstore?key=orderId1' 订阅配置项更新
以下是利用SDK订阅使用configstore存储组件的键[orderId1, orderId2]的代码示例。
using System; using System.Collections.Generic; using System.Threading.Tasks; using Dapr.Client; const string DAPR_CONFIGURATION_STORE = "configstore"; var CONFIGURATION_KEYS = new List<string> { "orderId1", "orderId2" }; var client = new DaprClientBuilder().Build(); // 订阅配置更改 SubscribeConfigurationResponse subscribe = await client.SubscribeConfiguration(DAPR_CONFIGURATION_STORE, CONFIGURATION_ITEMS); // 打印配置更改 await foreach (var items in subscribe.Source) { // 应用程序订阅配置更改时的首次调用仅返回订阅ID if (items.Keys.Count == 0) { Console.WriteLine("App subscribed to config changes with subscription id: " + subscribe.Id); subscriptionId = subscribe.Id; continue; } var cfg = System.Text.Json.JsonSerializer.Serialize(items); Console.WriteLine("Configuration update " + cfg); } 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing -- dotnet run using System; using Microsoft.AspNetCore.Hosting; using Microsoft.Extensions.Hosting; using Dapr.Client; using Dapr.Extensions.Configuration; using System.Collections.Generic; using System.Threading; namespace ConfigurationApi { public class Program { public static void Main(string[] args) { Console.WriteLine("Starting application."); CreateHostBuilder(args).Build().Run(); Console.WriteLine("Closing application."); } /// <summary> /// 创建WebHost Builder。 /// </summary> /// <param name="args">参数。</param> /// <returns>返回IHostbuilder。</returns> public static IHostBuilder CreateHostBuilder(string[] args) { var client = new DaprClientBuilder().Build(); return Host.CreateDefaultBuilder(args) .ConfigureAppConfiguration(config => { // 获取初始值并继续监视其更改。 config.AddDaprConfigurationStore("configstore", new List<string>() { "orderId1","orderId2" }, client, TimeSpan.FromSeconds(20)); config.AddStreamingDaprConfigurationStore("configstore", new List<string>() { "orderId1","orderId2" }, client, TimeSpan.FromSeconds(20)); }) .ConfigureWebHostDefaults(webBuilder => { webBuilder.UseStartup<Startup>(); }); } } } 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing -- dotnet run import io.dapr.client.DaprClientBuilder; import io.dapr.client.DaprClient; 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; //代码 private static final String CONFIG_STORE_NAME = "configstore"; private static String subscriptionId = null; public static void main(String[] args) throws Exception { try (DaprClient client = (new DaprClientBuilder()).build()) { // 订阅配置更改 List<String> keys = new ArrayList<>(); keys.add("orderId1"); keys.add("orderId2"); Flux<SubscribeConfigurationResponse> subscription = client.subscribeConfiguration(DAPR_CONFIGURATON_STORE,keys); // 读取配置更改20秒 subscription.subscribe((response) -> { // 首次响应包含订阅ID if (response.getItems() == null || response.getItems().isEmpty()) { subscriptionId = response.getSubscriptionId(); System.out.println("App subscribed to config changes with subscription id: " + subscriptionId); } else { response.getItems().forEach((k, v) -> { System.out.println("Configuration update for " + k + ": {'value':'" + v.getValue() + "'}"); }); } }); Thread.sleep(20000); } } 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing -- -- mvn spring-boot:run #依赖项 from dapr.clients import DaprClient #代码 def handler(id: str, resp: ConfigurationResponse): for key in resp.items: print(f"Subscribed item received key={key} value={resp.items[key].value} " f"version={resp.items[key].version} " f"metadata={resp.items[key].metadata}", flush=True) def executeConfiguration(): with DaprClient() as d: storeName = 'configurationstore' keys = ['orderId1', 'orderId2'] id = d.subscribe_configuration(store_name=storeName, keys=keys, handler=handler, config_metadata={}) print("Subscription ID is", id, flush=True) sleep(20) executeConfiguration() 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing -- python3 OrderProcessingService.py package main import ( "context" "fmt" "time" dapr "github.com/dapr/go-sdk/client" ) func main() { ctx := context.Background() client, err := dapr.NewClient() if err != nil { panic(err) } subscribeID, err := client.SubscribeConfigurationItems(ctx, "configstore", []string{"orderId1", "orderId2"}, func(id string, items map[string]*dapr.ConfigurationItem) { for k, v := range items { fmt.Printf("get updated config key = %s, value = %s version = %s \n", k, v.Value, v.Version) } }) if err != nil { panic(err) } time.Sleep(20*time.Second) } 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing -- go run main.go import { CommunicationProtocolEnum, DaprClient } from "@dapr/dapr"; // JS SDK尚不支持通过HTTP协议的配置API const protocol = CommunicationProtocolEnum.GRPC; const host = process.env.DAPR_HOST ?? "localhost"; const port = process.env.DAPR_GRPC_PORT ?? 3500; const DAPR_CONFIGURATION_STORE = "configstore"; const CONFIGURATION_ITEMS = ["orderId1", "orderId2"]; async function main() { const client = new DaprClient(host, port, protocol); // 订阅配置更新 try { const stream = await client.configuration.subscribeWithKeys( DAPR_CONFIGURATION_STORE, CONFIGURATION_ITEMS, (config) => { console.log("Configuration update", JSON.stringify(config.items)); } ); // 取消订阅配置更新并在20秒后退出应用程序 setTimeout(() => { stream.stop(); console.log("App unsubscribed to config changes"); process.exit(0); }, 20000); } catch (error) { console.log("Error subscribing to config updates, err:" + error); process.exit(1); } } main().catch((e) => console.error(e)); 导航到包含上述代码的目录，然后运行以下命令以启动Dapr sidecar和订阅者应用程序：
dapr run --app-id orderprocessing --app-protocol grpc --dapr-grpc-port 3500 -- node index.js 取消订阅配置项更新
在您订阅监视配置项后，您将收到所有订阅键的更新。要停止接收更新，您需要显式调用取消订阅API。
以下是展示如何使用取消订阅API取消订阅配置更新的代码示例。
using System; using System.Collections.Generic; using System.Threading.Tasks; using Dapr.Client; const string DAPR_CONFIGURATION_STORE = "configstore"; var client = new DaprClientBuilder().Build(); // 取消订阅配置更新并退出应用程序 async Task unsubscribe(string subscriptionId) { try { await client.UnsubscribeConfiguration(DAPR_CONFIGURATION_STORE, subscriptionId); Console.WriteLine("App unsubscribed from config changes"); Environment.Exit(0); } catch (Exception ex) { Console.WriteLine("Error unsubscribing from config updates: " + ex.Message); } } import io.dapr.client.DaprClientBuilder; import io.dapr.client.DaprClient; 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; //代码 private static final String CONFIG_STORE_NAME = "configstore"; private static String subscriptionId = null; public static void main(String[] args) throws Exception { try (DaprClient client = (new DaprClientBuilder()).build()) { // 取消订阅配置更改 UnsubscribeConfigurationResponse unsubscribe = client .unsubscribeConfiguration(subscriptionId, DAPR_CONFIGURATON_STORE).block(); if (unsubscribe.getIsUnsubscribed()) { System.out.println("App unsubscribed to config changes"); } else { System.out.println("Error unsubscribing to config updates, err:" + unsubscribe.getMessage()); } } catch (Exception e) { System.out.println("Error unsubscribing to config updates," + e.getMessage()); System.exit(1); } } import asyncio import time import logging from dapr.clients import DaprClient subscriptionID = "" with DaprClient() as d: isSuccess = d.unsubscribe_configuration(store_name='configstore', id=subscriptionID) print(f"Unsubscribed successfully? {isSuccess}", flush=True) package main import ( "context" "encoding/json" "fmt" "log" "os" "time" dapr "github.com/dapr/go-sdk/client" ) var DAPR_CONFIGURATION_STORE = "configstore" var subscriptionID = "" func main() { client, err := dapr.NewClient() if err != nil { log.Panic(err) } ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) defer cancel() if err := client.UnsubscribeConfigurationItems(ctx, DAPR_CONFIGURATION_STORE , subscriptionID); err != nil { panic(err) } } import { CommunicationProtocolEnum, DaprClient } from "@dapr/dapr"; // JS SDK尚不支持通过HTTP协议的配置API const protocol = CommunicationProtocolEnum.GRPC; const host = process.env.DAPR_HOST ?? "localhost"; const port = process.env.DAPR_GRPC_PORT ?? 3500; const DAPR_CONFIGURATION_STORE = "configstore"; const CONFIGURATION_ITEMS = ["orderId1", "orderId2"]; async function main() { const client = new DaprClient(host, port, protocol); try { const stream = await client.configuration.subscribeWithKeys( DAPR_CONFIGURATION_STORE, CONFIGURATION_ITEMS, (config) => { console.log("Configuration update", JSON.stringify(config.items)); } ); setTimeout(() => { // 取消订阅配置更新 stream.stop(); console.log("App unsubscribed to config changes"); process.exit(0); }, 20000); } catch (error) { console.log("Error subscribing to config updates, err:" + error); process.exit(1); } } main().catch((e) => console.error(e)); curl 'http://localhost:<DAPR_HTTP_PORT>/v1.0/configuration/configstore/<subscription-id>/unsubscribe' Invoke-RestMethod -Uri 'http://localhost:<DAPR_HTTP_PORT>/v1.0/configuration/configstore/<subscription-id>/unsubscribe' 下一步
- 阅读配置API概述