func (n *node) process(e raftpb.Entry, pending chan struct{}) {
if e.Type != raftpb.EntryNormal {
return
}
pending <- struct{}{} // This will block until we can write to it.
var proposal task.Proposal
x.Check(proposal.Unmarshal(e.Data))
var err error
if proposal.Mutations != nil {
err = n.processMutation(e, proposal.Mutations)
} else if proposal.Membership != nil {
err = n.processMembership(e, proposal.Membership)
}
n.props.Done(proposal.Id, err)
<-pending // Release one.
}
func (n *node) ProposeAndWait(ctx context.Context, proposal *task.Proposal) error {
if n.raft == nil {
return x.Errorf("RAFT isn't initialized yet")
}
proposal.Id = rand.Uint32()
slice := slicePool.Get().([]byte)
if len(slice) < proposal.Size() {
slice = make([]byte, proposal.Size())
}
defer slicePool.Put(slice)
upto, err := proposal.MarshalTo(slice)
if err != nil {
return err
}
proposalData := slice[:upto]
che := make(chan error, 1)
n.props.Store(proposal.Id, che)
if err = n.raft.Propose(ctx, proposalData); err != nil {
return x.Wrapf(err, "While proposing")
}
// Wait for the proposal to be committed.
if proposal.Mutations != nil {
x.Trace(ctx, "Waiting for the proposal: mutations.")
} else {
x.Trace(ctx, "Waiting for the proposal: membership update.")
}
select {
case err = <-che:
x.TraceError(ctx, err)
return err
case <-ctx.Done():
return ctx.Err()
}
}