async switchClientIfRequired()

in common/lib/plugins/read_write_splitting_plugin.ts [210:249]
38 lines of code
14 McCabe index (conditional complexity)

  async switchClientIfRequired(readOnly: boolean) {
    const currentClient = this.pluginService.getCurrentClient();
    if (!(await currentClient.isValid())) {
      logAndThrowError(Messages.get("ReadWriteSplittingPlugin.setReadOnlyOnClosedClient", currentClient.targetClient?.id ?? "undefined client"));
    }
    try {
      await this.pluginService.refreshHostList();
    } catch {
      // pass
    }

    const hosts: HostInfo[] = this.pluginService.getHosts();
    if (hosts == null || hosts.length === 0) {
      logAndThrowError(Messages.get("ReadWriteSplittingPlugin.emptyHostList"));
    }
    const currentHost = this.pluginService.getCurrentHostInfo();
    if (currentHost == null) {
      logAndThrowError(Messages.get("ReadWriteSplittingPlugin.unavailableHostInfo"));
    } else if (readOnly) {
      if (!this.pluginService.isInTransaction() && currentHost.role != HostRole.READER) {
        try {
          await this.switchToReaderTargetClient(hosts);
        } catch (error: any) {
          if (!(await currentClient.isValid())) {
            logAndThrowError(Messages.get("ReadWriteSplittingPlugin.errorSwitchingToReader", error.message));
          }
          logger.warn(Messages.get("ReadWriteSplittingPlugin.fallbackToWriter", currentHost.url));
        }
      }
    } else if (currentHost.role != HostRole.WRITER) {
      if (this.pluginService.isInTransaction()) {
        logAndThrowError(Messages.get("ReadWriteSplittingPlugin.setReadOnlyFalseInTransaction"));
      }
      try {
        await this.switchToWriterTargetClient(hosts);
      } catch (error: any) {
        logAndThrowError(Messages.get("ReadWriteSplittingPlugin.errorSwitchingToWriter", error.message));
      }
    }
  }