PeerRequestContext getPeerRequestContext(final String groupId, final PeerPair pair) {
        ConcurrentMap<PeerPair, PeerRequestContext> groupContexts = this.peerRequestContexts.get(groupId);

        if (groupContexts == null) {
            return null;
        }
        return groupContexts.get(pair);
    }
A peer pair
@author boyan(boyan@antfin.com)
jraft-core/src/main/java/com/alipay/sofa/jraft/rpc/impl/core/AppendEntriesRequestProcessor.java