Struct cdc::CdcObserver

pub struct CdcObserver {
    sched: Scheduler<Task>,
    observe_regions: Arc<RwLock<HashMap<u64, ObserveID>>>,
    cmd_batches: RefCell<Vec<CmdBatch>>,
    last_batch_observing: RefCell<bool>,
}

An Observer for CDC.

It observes raftstore internal events, such as:

1. Raft role change events,
2. Apply command events.

Fields

sched: Scheduler<Task>

observe_regions: Arc<RwLock<HashMap<u64, ObserveID>>>

cmd_batches: RefCell<Vec<CmdBatch>>

last_batch_observing: RefCell<bool>

Implementations

impl CdcObserver

pub fn new(sched: Scheduler<Task>) -> CdcObserver

Create a new CdcObserver.

Events are strong ordered, so sched must be implemented as a FIFO queue.

pub fn register_to(&self, coprocessor_host: &mut CoprocessorHost<RocksEngine>)

pub fn subscribe_region(
    &self,
    region_id: u64,
    observe_id: ObserveID
) -> Option<ObserveID>

Subscribe an region, the observer will sink events of the region into its scheduler.

Return pervious ObserveID if there is one.

pub fn unsubscribe_region(
    &self,
    region_id: u64,
    observe_id: ObserveID
) -> Option<ObserveID>

Stops observe the region.

Return ObserverID if unsubscribe successfully.

pub fn is_subscribed(&self, region_id: u64) -> Option<ObserveID>

Check whether the region is subscribed or not.

Trait Implementations

impl Clone for CdcObserver

fn clone(&self) -> CdcObserver

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<E: KvEngine> CmdObserver<E> for CdcObserver

fn on_prepare_for_apply(
    &self,
    cdc: &ObserveHandle,
    rts: &ObserveHandle,
    region_id: u64
)

Hook to call after preparing for applying write requests.

fn on_apply_cmd(
    &self,
    cdc_id: ObserveID,
    rts_id: ObserveID,
    region_id: u64,
    cmd: &Cmd
)

Hook to call after applying a write request.

fn on_flush_apply(&self, engine: E)

Hook to call after flushing writes to db.

impl Coprocessor for CdcObserver

pub fn start(&self)

pub fn stop(&self)

impl RegionChangeObserver for CdcObserver

fn on_region_changed(
    &self,
    ctx: &mut ObserverContext<'_>,
    event: RegionChangeEvent,
    _: StateRole
)

Hook to call when a region changed on this TiKV

impl RoleObserver for CdcObserver

fn on_role_change(&self, ctx: &mut ObserverContext<'_>, role: StateRole)

Hook to call when role of a peer changes.