Golang RangeDescriptor.RSpan方法代碼示例

//.........這裏部分代碼省略.........
			// If sending succeeded, break this loop.
			if pErr == nil {
				finished = true
				break
			}

			log.VTracef(1, ctx, "reply error %s: %s", ba, pErr)

			// Error handling: If the error indicates that our range
			// descriptor is out of date, evict it from the cache and try
			// again. Errors that apply only to a single replica were
			// handled in send().
			//
			// TODO(bdarnell): Don't retry endlessly. If we fail twice in a
			// row and the range descriptor hasn't changed, return the error
			// to our caller.
			switch tErr := pErr.GetDetail().(type) {
			case *roachpb.SendError:
				// We've tried all the replicas without success. Either
				// they're all down, or we're using an out-of-date range
				// descriptor. Invalidate the cache and try again with the new
				// metadata.
				if err := evictToken.Evict(ctx); err != nil {
					return nil, roachpb.NewError(err), false
				}
				continue
			case *roachpb.RangeKeyMismatchError:
				// Range descriptor might be out of date - evict it. This is
				// likely the result of a range split. If we have new range
				// descriptors, insert them instead as long as they are different
				// from the last descriptor to avoid endless loops.
				var replacements []roachpb.RangeDescriptor
				different := func(rd *roachpb.RangeDescriptor) bool {
					return !desc.RSpan().Equal(rd.RSpan())
				}
				if tErr.MismatchedRange != nil && different(tErr.MismatchedRange) {
					replacements = append(replacements, *tErr.MismatchedRange)
				}
				if tErr.SuggestedRange != nil && different(tErr.SuggestedRange) {
					if includesFrontOfCurSpan(tErr.SuggestedRange) {
						replacements = append(replacements, *tErr.SuggestedRange)

					}
				}
				// Same as Evict() if replacements is empty.
				if err := evictToken.EvictAndReplace(ctx, replacements...); err != nil {
					return nil, roachpb.NewError(err), false
				}
				// On addressing errors, don't backoff; retry immediately.
				r.Reset()
				if log.V(1) {
					log.Warning(ctx, tErr)
				}
				continue
			}
			break
		}

		// Immediately return if querying a range failed non-retryably.
		if pErr != nil {
			return nil, pErr, false
		} else if !finished {
			select {
			case <-ds.rpcRetryOptions.Closer:
				return nil, roachpb.NewError(&roachpb.NodeUnavailableError{}), false
			case <-ctx.Done():

//.........這裏部分代碼省略.........
			switch tErr := pErr.GetDetail().(type) {
			case *roachpb.SendError:
				// For an RPC error to occur, we must've been unable to contact
				// any replicas. In this case, likely all nodes are down (or
				// not getting back to us within a reasonable amount of time).
				// We may simply not be trying to talk to the up-to-date
				// replicas, so clearing the descriptor here should be a good
				// idea.
				if err := evictToken.Evict(); err != nil {
					return nil, roachpb.NewError(err), false
				}
				if tErr.CanRetry() {
					continue
				}
			case *roachpb.RangeNotFoundError:
				// Range descriptor might be out of date - evict it. This is
				// likely the result of a rebalance.
				if err := evictToken.Evict(); err != nil {
					return nil, roachpb.NewError(err), false
				}
				// On addressing errors, don't backoff; retry immediately.
				r.Reset()
				if log.V(1) {
					log.Warning(tErr)
				}
				continue
			case *roachpb.RangeKeyMismatchError:
				// Range descriptor might be out of date - evict it. This is
				// likely the result of a range split. If we have new range
				// descriptors, insert them instead as long as they are different
				// from the last descriptor to avoid endless loops.
				var replacements []roachpb.RangeDescriptor
				different := func(rd *roachpb.RangeDescriptor) bool {
					return !desc.RSpan().Equal(rd.RSpan())
				}
				if tErr.MismatchedRange != nil && different(tErr.MismatchedRange) {
					replacements = append(replacements, *tErr.MismatchedRange)
				}
				if tErr.SuggestedRange != nil && different(tErr.SuggestedRange) {
					if includesFrontOfCurSpan(tErr.SuggestedRange) {
						replacements = append(replacements, *tErr.SuggestedRange)

					}
				}
				// Same as Evict() if replacements is empty.
				if err := evictToken.EvictAndReplace(replacements...); err != nil {
					return nil, roachpb.NewError(err), false
				}
				// On addressing errors, don't backoff; retry immediately.
				r.Reset()
				if log.V(1) {
					log.Warning(tErr)
				}
				continue
			case *roachpb.NotLeaderError:
				newLeader := tErr.Leader
				if newLeader != nil {
					// Verify that leader is a known replica according to the
					// descriptor. If not, we've got a stale range descriptor;
					// evict cache.
					if i, _ := desc.FindReplica(newLeader.StoreID); i == -1 {
						if log.V(1) {
							log.Infof("error indicates unknown leader %s, expunging descriptor %s", newLeader, desc)
						}
						if err := evictToken.Evict(); err != nil {
							return nil, roachpb.NewError(err), false