Reading from remote clusters via RPC proxy

Starting from version YTsaurus 25.2, it became possible to perform requests to remote clusters through the RPC Proxy.

Configuration

This functionality is configured through the dynamic config.

For RPC proxies, the configuration of this functionality is located at /api/multiproxy in the dynamic config of RPC proxies. In the case of an RPC Proxy embedded into a Job Proxy, the configuration is located at /exec_node/job_controller/job_proxy/job_proxy_api_service/multiproxy in the dynamic config of the nodes.

The configuration consists of two parts:

1. Description of presets with allowed methods.
2. Mapping from a cluster name to a preset name.

Example configuration for reading from the cluster remote_cluster using the SDK:

{
  "presets" = {
    "allow_sdk_read" = {
      "enabled_methods" = "read";
      "method_overrides" = {
        "StartTransaction" = "explicitly_enabled";
        "AbortTransaction" = "explicitly_enabled";
        "AttachTransaction" = "explicitly_enabled";
        "PingTransaction" = "explicitly_enabled";
        "LockNode" = "explicitly_enabled";
      }
    }
  };
  "cluster_presets" = {
    "remote_cluster" = "allow_sdk_read";
  }
}

The remote_cluster must be present in the cluster list in //sys/clusters.