Enum FrontendClient

pub enum FrontendClient {
    Distributed {
        meta_client: Arc<MetaClient>,
        chnl_mgr: ChannelManager,
        auth: Option<FlowAuthHeader>,
    },
    Standalone {
        database_client: Arc<Mutex<Option<Weak<dyn GrpcQueryHandlerWithBoxedError>>>>,
    },
}

A simple frontend client able to execute sql using grpc protocol

This is for computation-heavy query which need to offload computation to frontend, lifting the load from flownode

Variants

Distributed

Fields

meta_client: Arc<MetaClient>

chnl_mgr: ChannelManager

auth: Option<FlowAuthHeader>

Standalone

Fields

database_client: Arc<Mutex<Option<Weak<dyn GrpcQueryHandlerWithBoxedError>>>>

for the sake of simplicity still use grpc even in standalone mode notice the client here should all be lazy, so that can wait after frontend is booted then make conn

Implementations

impl FrontendClient

pub fn from_empty_grpc_handler() -> (Self, Arc<Mutex<Option<Weak<dyn GrpcQueryHandlerWithBoxedError>>>>)

Create a new empty frontend client, with a HandlerMutable to set the grpc handler later

pub fn from_meta_client( meta_client: Arc<MetaClient>, auth: Option<FlowAuthHeader>, ) -> Self

pub fn from_grpc_handler( grpc_handler: Weak<dyn GrpcQueryHandlerWithBoxedError>, ) -> Self

impl FrontendClient

pub(crate) async fn scan_for_frontend( &self, ) -> Result<Vec<(NodeInfoKey, NodeInfo)>, Error>

scan for available frontend from metadata

async fn get_random_active_frontend( &self, catalog: &str, schema: &str, ) -> Result<DatabaseWithPeer, Error>

Get the frontend with recent enough(less than 1 minute from now) last_activity_ts and is able to process query

pub async fn create( &self, create: CreateTableExpr, catalog: &str, schema: &str, ) -> Result<u32, Error>

pub(crate) async fn handle( &self, req: Request, catalog: &str, schema: &str, peer_desc: &mut Option<PeerDesc>, ) -> Result<u32, Error>

Handle a request to frontend

Trait Implementations

impl Clone for FrontendClient

fn clone(&self) -> FrontendClient

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FrontendClient

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.