feat: read-write splitting plugin

common/lib/connection_plugin_chain_builder.ts

@@ -26,6 +26,7 @@ import { ExecuteTimePluginFactory } from "./plugins/execute_time_plugin";
 import { ConnectTimePluginFactory } from "./plugins/connect_time_plugin";
 import { AwsSecretsManagerPluginFactory } from "./authentication/aws_secrets_manager_plugin";
 import { ConnectionProvider } from "./connection_provider";
+import { ReadWriteSplittingPluginFactory } from "./plugins/read_write_splitting";
 import { StaleDnsPluginFactory } from "./plugins/stale_dns/stale_dns_plugin";
 
 export class PluginFactoryInfo {}
@@ -42,6 +43,8 @@ export class ConnectionPluginChainBuilder {
     ["connectTime", ConnectTimePluginFactory],
     ["secretsManager", AwsSecretsManagerPluginFactory],
     ["failover", FailoverPluginFactory],
+    ["readWriteSplitting", ReadWriteSplittingPluginFactory],
+    ["failover", FailoverPluginFactory],
     ["staleDns", StaleDnsPluginFactory]
   ]);
 

common/lib/driver_connection_provider.ts

@@ -106,7 +106,7 @@ export class DriverConnectionProvider implements ConnectionProvider {
   getHostInfoByStrategy(hosts: HostInfo[], role: HostRole, strategy: string, props?: Map<string, any>): HostInfo {
     const acceptedStrategy = DriverConnectionProvider.acceptedStrategies.get(strategy);
     if (!acceptedStrategy) {
-      throw new AwsWrapperError(Messages.get("ConnectionProvider.unsupportedHostInfoSelectorStrategy", strategy, "DriverConnectionProvider"));
+      throw new AwsWrapperError(Messages.get("ConnectionProvider.unsupportedHostSelectorStrategy", strategy, "DriverConnectionProvider")); // TODO
     }
     return acceptedStrategy.getHost(hosts, role, props);
   }

common/lib/host_info.ts

@@ -26,7 +26,7 @@ export class HostInfo {
   private readonly _host: string;
   private readonly _port: number;
   private _availability: HostAvailability;
-  private readonly _role: HostRole;
+  private _role: HostRole;
   protected aliases: Set<string> = new Set<string>();
   private _allAliases: Set<string> = new Set<string>();
   private readonly _weight: number; // Greater or equal 0. Lesser the weight, the healthier node.
@@ -129,6 +129,10 @@ export class HostInfo {
     return this._role;
   }
 
+  set role(value: HostRole) {
+    this._role = value;
+  }
+
   get allAliases(): Set<string> {
     return this._allAliases;
   }

common/lib/plugin_manager.ts

@@ -27,6 +27,8 @@ import { HostChangeOptions } from "./host_change_options";
 import { OldConnectionSuggestionAction } from "./old_connection_suggestion_action";
 import { HostRole } from "./host_role";
 import { ConnectionProvider } from "./connection_provider";
+import { ConnectionProviderManager } from "./connection_provider_manager";
+import { chain } from "lodash";
 
 type PluginFunc<T> = (plugin: ConnectionPlugin, targetFunc: () => Promise<T>) => Promise<T>;
 
@@ -73,6 +75,7 @@ export class PluginManager {
   private readonly _plugins: ConnectionPlugin[] = [];
   private pluginServiceManagerContainer: PluginServiceManagerContainer;
   private props: Map<string, any>;
+  private readonly _defaultConnProvider: ConnectionProvider;
 
   constructor(
     pluginServiceManagerContainer: PluginServiceManagerContainer,
@@ -83,6 +86,7 @@ export class PluginManager {
     this.pluginServiceManagerContainer = pluginServiceManagerContainer;
     this.pluginServiceManagerContainer.pluginManager = this;
     this.props = props;
+    this._defaultConnProvider = defaultConnProvider;
     if (this.pluginServiceManagerContainer.pluginService != null) {
       this._plugins = new ConnectionPluginChainBuilder().getPlugins(
         this.pluginServiceManagerContainer.pluginService,
@@ -253,4 +257,8 @@ export class PluginManager {
 
     throw new AwsWrapperError("The driver does not support the requested host selection strategy: " + strategy);
   }
+
+  getDefaultConnProvider(): ConnectionProvider {
+    return this._defaultConnProvider;
+  }
 }

common/lib/plugin_service.ts

@@ -135,6 +135,10 @@ export class PluginService implements ErrorHandler, HostListProviderService {
     return false;
   }
 
+  acceptsStrategy(role: HostRole, strategy: string): boolean {
+    return this.pluginServiceManagerContainer.pluginManager?.acceptsStrategy(role, strategy) ?? false;
+  }
+
   async forceRefreshHostList(): Promise<void>;
   async forceRefreshHostList(targetClient?: any): Promise<void>;
   async forceRefreshHostList(targetClient?: any): Promise<void> {
@@ -248,6 +252,15 @@ export class PluginService implements ErrorHandler, HostListProviderService {
     throw new AwsWrapperError("AwsClient is missing create target client function."); // This should not be reached
   }
 
+  getHostInfoByStrategy(role: HostRole, strategy: string): HostInfo | undefined {
+    const pluginManager = this.pluginServiceManagerContainer.pluginManager;
+    return pluginManager?.getHostInfoByStrategy(role, strategy);
+  }
+
+  async getHostRole(client: AwsClient): Promise<HostRole> {
+    return (await this._hostListProvider?.getHostRole(client, this.dialect)) ?? HostRole.UNKNOWN;
+  }
+
   connect<T>(hostInfo: HostInfo, props: Map<string, any>, connectFunc: () => Promise<T>) {
     if (connectFunc) {
       return this.pluginServiceManagerContainer.pluginManager?.connect(hostInfo, props, false, connectFunc);