splits out gossip Protocol out of cluster_info.rs (#3488)

Reorganizing this code in preparation of upcoming changes to 
gossip Protocol (de)serialization.

Author: behzadnouri

gossip/src/cluster_info.rs

@@ -1,6 +1,5 @@
 use {
     crate::{
-        cluster_info::MAX_ACCOUNTS_HASHES,
         contact_info::ContactInfo,
         deprecated,
         duplicate_shred::{DuplicateShred, DuplicateShredIndex, MAX_DUPLICATE_SHREDS},
@@ -24,6 +23,10 @@ use {
 
 pub(crate) const MAX_WALLCLOCK: u64 = 1_000_000_000_000_000;
 pub(crate) const MAX_SLOT: u64 = 1_000_000_000_000_000;
+/// Maximum number of hashes in AccountsHashes a node publishes
+/// such that the serialized size of the push/pull message stays below
+/// PACKET_DATA_SIZE.
+const MAX_ACCOUNTS_HASHES: usize = 16;
 
 pub(crate) type VoteIndex = u8;
 // TODO: Remove this in favor of vote_state::MAX_LOCKOUT_HISTORY once

gossip/src/crds_data.rs

@@ -6,7 +6,6 @@
 
 use {
     crate::{
-        cluster_info::Ping,
         cluster_info_metrics::GossipStats,
         contact_info::ContactInfo,
         crds::{Crds, GossipRoute},
@@ -17,6 +16,7 @@ use {
         crds_value::CrdsValue,
         duplicate_shred::{self, DuplicateShredIndex, MAX_DUPLICATE_SHREDS},
         ping_pong::PingCache,
+        protocol::Ping,
     },
     itertools::Itertools,
     rand::{CryptoRng, Rng},

gossip/src/crds_gossip.rs

@@ -13,14 +13,14 @@
 
 use {
     crate::{
-        cluster_info::Ping,
         cluster_info_metrics::GossipStats,
         contact_info::ContactInfo,
         crds::{Crds, GossipRoute, VersionedCrdsValue},
         crds_gossip,
         crds_gossip_error::CrdsGossipError,
         crds_value::CrdsValue,
         ping_pong::PingCache,
+        protocol::Ping,
     },
     itertools::Itertools,
     rand::{
@@ -655,9 +655,9 @@ pub(crate) mod tests {
     use {
         super::*,
         crate::{
-            cluster_info::Protocol,
             crds_data::{CrdsData, Vote},
             legacy_contact_info::LegacyContactInfo,
+            protocol::Protocol,
         },
         itertools::Itertools,
         rand::{seq::SliceRandom, SeedableRng},

gossip/src/crds_gossip_pull.rs

@@ -13,11 +13,12 @@
 
 use {
     crate::{
-        cluster_info::{Ping, CRDS_UNIQUE_PUBKEY_CAPACITY},
+        cluster_info::CRDS_UNIQUE_PUBKEY_CAPACITY,
         crds::{Crds, CrdsError, Cursor, GossipRoute},
         crds_gossip,
         crds_value::CrdsValue,
         ping_pong::PingCache,
+        protocol::Ping,
         push_active_set::PushActiveSet,
         received_cache::ReceivedCache,
     },

gossip/src/crds_gossip_push.rs

@@ -227,8 +227,8 @@ mod tests {
     use {
         super::*,
         crate::{
-            cluster_info::DUPLICATE_SHRED_MAX_PAYLOAD_SIZE,
             duplicate_shred::{from_shred, tests::new_rand_shred},
+            protocol::DUPLICATE_SHRED_MAX_PAYLOAD_SIZE,
         },
         crossbeam_channel::unbounded,
         itertools::Itertools,

gossip/src/duplicate_shred_handler.rs

@@ -1,7 +1,7 @@
 use {
     crate::{
-        cluster_info::MAX_CRDS_OBJECT_SIZE,
         crds_data::{self, MAX_SLOT, MAX_WALLCLOCK},
+        protocol::MAX_CRDS_OBJECT_SIZE,
     },
     bincode::serialized_size,
     bv::BitVec,

gossip/src/epoch_slots.rs

@@ -23,6 +23,7 @@ pub mod gossip_service;
 #[macro_use]
 mod legacy_contact_info;
 pub mod ping_pong;
+mod protocol;
 mod push_active_set;
 mod received_cache;
 pub mod restart_crds_values;