WIP filling in core aggregator match arms and various other tweaks

backend/Cargo.lock

@@ -1193,10 +1193,12 @@ dependencies = [
  "hex",
  "http",
  "log",
+ "once_cell",
  "primitive-types",
  "serde",
  "serde_json",
  "simple_logger",
+ "smallvec",
  "soketto",
  "structopt",
  "thiserror",

backend/common/src/internal_messages.rs

@@ -1,7 +1,7 @@
 use std::net::IpAddr;
 
 use crate::node::Payload;
-use crate::types::{NodeDetails};
+use crate::types::{NodeDetails, BlockHash};
 use crate::assign_id::Id;
 use serde::{Deserialize, Serialize};
 
@@ -10,7 +10,7 @@ use serde::{Deserialize, Serialize};
 pub type LocalId = Id;
 
 /// A global ID assigned to messages from each different pair of ConnId+LocalId.
-pub type GlobalId = Id;
+pub type GlobalId = usize;
 
 /// Message sent from the shard to the backend core
 #[derive(Deserialize, Serialize, Debug, Clone)]
@@ -20,6 +20,7 @@ pub enum FromShardAggregator {
     	ip: Option<IpAddr>,
     	node: NodeDetails,
     	local_id: LocalId,
+        genesis_hash: BlockHash
     },
     /// Send a message payload to update details for a node
     UpdateNode {

backend/shard/src/aggregator.rs

@@ -1,4 +1,4 @@
-use common::{internal_messages::{self, LocalId}, node, assign_id::AssignId};
+use common::{internal_messages::{self, LocalId}, node, assign_id::AssignId, types::BlockHash};
 use std::sync::Arc;
 use std::sync::atomic::AtomicU64;
 use futures::{channel::mpsc, future};
@@ -42,6 +42,7 @@ pub enum FromWebsocket {
         message_id: node::NodeMessageId,
         ip: Option<std::net::IpAddr>,
         node: common::types::NodeDetails,
+        genesis_hash: BlockHash
     },
     /// Update/pass through details about a node.
     Update {
@@ -150,7 +151,7 @@ impl Aggregator {
                     // connections where we mute one set of messages it sends and not others.
                     close_connections.push(close_connection);
                 },
-                ToAggregator::FromWebsocket(conn_id, FromWebsocket::Add { message_id, ip, node }) => {
+                ToAggregator::FromWebsocket(conn_id, FromWebsocket::Add { message_id, ip, node, genesis_hash }) => {
                     // Don't bother doing anything else if we're disconnected, since we'll force the
                     // ndoe to reconnect anyway when the backend does:
                     if !connected_to_telemetry_core { continue }
@@ -162,6 +163,7 @@ impl Aggregator {
                     let _ = tx_to_telemetry_core.send(FromShardAggregator::AddNode {
                         ip,
                         node,
+                        genesis_hash,
                         local_id
                     }).await;
                 },

backend/shard/src/main.rs

@@ -157,6 +157,7 @@ async fn handle_websocket_connection<S>(mut websocket: ws::WebSocket, mut tx_to_
                         message_id,
                         ip: addr.map(|a| a.ip()),
                         node: info.node,
+                        genesis_hash: info.genesis_hash,
                     }).await;
                 }
                 // Anything that's not an "Add" is an Update. The aggregator will ignore

backend/telemetry/Cargo.toml

@@ -12,10 +12,12 @@ futures = "0.3.15"
 hex = "0.4.3"
 http = "0.2.4"
 log = "0.4.14"
+once_cell = "1.8.0"
 primitive-types = { version = "0.9.0", features = ["serde"] }
 serde = { version = "1.0.126", features = ["derive"] }
 serde_json = "1.0.64"
 simple_logger = "1.11.0"
+smallvec = "1.6.1"
 soketto = "0.6.0"
 structopt = "0.3.21"
 thiserror = "1.0.25"

backend/telemetry/src/aggregator.rs

@@ -1,4 +1,9 @@
-use common::{internal_messages::{GlobalId, LocalId}, node, assign_id::AssignId};
+use common::{
+    internal_messages::{GlobalId, LocalId},
+    node,
+    assign_id::AssignId,
+    util::now
+};
 use std::{str::FromStr, sync::Arc};
 use std::sync::atomic::AtomicU64;
 use futures::channel::{ mpsc, oneshot };
@@ -7,6 +12,7 @@ use tokio::net::TcpStream;
 use tokio_util::compat::{ TokioAsyncReadCompatExt };
 use std::collections::{ HashMap, HashSet };
 use crate::state::State;
+use crate::feed_message::{ self, FeedMessageSerializer };
 
 /// A unique Id is assigned per websocket connection (or more accurately,
 /// per feed socket and per shard socket). This can be combined with the
@@ -33,6 +39,7 @@ pub enum FromShardWebsocket {
         local_id: LocalId,
         ip: Option<std::net::IpAddr>,
         node: common::types::NodeDetails,
+        genesis_hash: common::types::BlockHash
     },
     /// Update/pass through details about a node.
     Update {
@@ -68,13 +75,9 @@ pub enum FromFeedWebsocket {
         chain: Box<str>
     },
     /// The feed wants finality info for the chain, too.
-    SendFinality {
+    SendFinality,
-        chain: Box<str>
-    },
     /// The feed doesn't want any more finality info for the chain.
-    NoMoreFinality {
+    NoMoreFinality,
-        chain: Box<str>
-    },
     /// An explicit ping message.
     Ping {
         chain: Box<str>
@@ -92,8 +95,8 @@ impl FromStr for FromFeedWebsocket {
         match cmd {
             "ping" => Ok(FromFeedWebsocket::Ping { chain }),
             "subscribe" => Ok(FromFeedWebsocket::Subscribe { chain }),
-            "send-finality" => Ok(FromFeedWebsocket::SendFinality { chain }),
+            "send-finality" => Ok(FromFeedWebsocket::SendFinality),
-            "no-more-finality" => Ok(FromFeedWebsocket::NoMoreFinality { chain }),
+            "no-more-finality" => Ok(FromFeedWebsocket::NoMoreFinality),
             _ => return Err(anyhow::anyhow!("Command {} not recognised", cmd))
         }
     }
@@ -102,7 +105,7 @@ impl FromStr for FromFeedWebsocket {
 /// The aggregator can these messages back to a feed connection.
 #[derive(Debug)]
 pub enum ToFeedWebsocket {
-
+    Bytes(Vec<u8>)
 }
 
 #[derive(Clone)]
@@ -142,7 +145,7 @@ impl Aggregator {
     // any more, this task will gracefully end.
     async fn handle_messages(mut rx_from_external: mpsc::Receiver<ToAggregator>, denylist: Vec<String>) {
 
-        let mut node_state = State::new();
+        let mut node_state = State::new(denylist);
 
         // Maintain mappings from the shard connection ID and local ID of messages to a global ID
         // that uniquely identifies nodes in our node state.
@@ -152,46 +155,124 @@ impl Aggregator {
         let mut feed_channels = HashMap::new();
         let mut shard_channels = HashMap::new();
 
-        // What chains have aour feeds subscribed to (one at a time at the mo):
+        // What chains have our feeds subscribed to (one at a time at the mo)?
+        // Both of these need to be kept in sync (should move to own struct eventually).
         let mut feed_conn_id_to_chain: HashMap<ConnId, Box<str>> = HashMap::new();
         let mut chain_to_feed_conn_ids: HashMap<Box<str>, HashSet<ConnId>> = HashMap::new();
+
+        // Which feeds want finality info too?
         let mut feed_conn_id_finality: HashSet<ConnId> = HashSet::new();
 
         // Now, loop and receive messages to handle.
         while let Some(msg) = rx_from_external.next().await {
             match msg {
-                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Initialize { channel }) => {
+                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Initialize { mut channel }) => {
-                    feed_channels.insert(feed_conn_id, channel);
+                    feed_channels.insert(feed_conn_id, channel.clone());
 
-                    // TODO: `feed::AddedChain` message to tell feed about current chains.
+                    // Tell the new feed subscription some basic things to get it going:
-                },
+                    let mut feed_serializer = FeedMessageSerializer::new();
-                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Ping { chain }) => {
+                    feed_serializer.push(feed_message::Version(31));
-                    // TODO: Return with feed::Pong(chain) feed message.
+                    for chain in node_state.iter_chains() {
-                },
+                        feed_serializer.push(feed_message::AddedChain(
-                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Subscribe { chain }) => {
+                            chain.label(),
-                    // Unsubscribe from previous chain if subscribed to one:
+                            chain.node_count()
-                    if let Some(feed_ids) = chain_to_feed_conn_ids.get_mut(&chain) {
+                        ));
-                        feed_ids.remove(&feed_conn_id);
                     }
 
-                    // Subscribe to the new chain:
+                    // Send this to the channel that subscribed:
-                    feed_conn_id_to_chain.insert(feed_conn_id, chain.clone());
+                    if let Some(bytes) = feed_serializer.into_finalized() {
-                    chain_to_feed_conn_ids.entry(chain).or_default().insert(feed_conn_id);
+                        let _ = channel.send(ToFeedWebsocket::Bytes(bytes)).await;
+                    }
+                },
+                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Ping { chain }) => {
+                    let feed_channel = match feed_channels.get_mut(&feed_conn_id) {
+                        Some(chan) => chan,
+                        None => continue
+                    };
 
+                    // Pong!
+                    let mut feed_serializer = FeedMessageSerializer::new();
+                    feed_serializer.push(feed_message::Pong(&chain));
+                    if let Some(bytes) = feed_serializer.into_finalized() {
+                        let _ = feed_channel.send(ToFeedWebsocket::Bytes(bytes)).await;
+                    }
                 },
-                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::SendFinality { chain: _ }) => {
+                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::Subscribe { chain }) => {
-                    feed_conn_id_finality.insert(feed_conn_id);
+                    let feed_channel = match feed_channels.get_mut(&feed_conn_id) {
-                    // TODO: Do we care about the chain here?
+                        Some(chan) => chan,
-                },
+                        None => continue
-                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::NoMoreFinality { chain: _ }) => {
+                    };
+
+                    // Unsubscribe from previous chain if subscribed to one:
+                    let old_chain_label = feed_conn_id_to_chain.remove(&feed_conn_id);
+                    if let Some(old_chain_label) = &old_chain_label {
+                        if let Some(map) = chain_to_feed_conn_ids.get_mut(old_chain_label) {
+                            map.remove(&feed_conn_id);
+                        }
+                    }
+
+                    // Untoggle request for finality feeds:
+                    feed_conn_id_finality.remove(&feed_conn_id);
+
+                    // Get the chain we're subscribing to, ignoring the rest if it doesn't exist.
+                    let chain = match node_state.get_chain_by_label(&chain) {
+                        Some(chain) => chain,
+                        None => continue
+                    };
+
+                    // Send messages to the feed about the new chain:
+                    let mut feed_serializer = FeedMessageSerializer::new();
+                    if let Some(old_chain_label) = old_chain_label {
+                        feed_serializer.push(feed_message::UnsubscribedFrom(&old_chain_label));
+                    }
+                    feed_serializer.push(feed_message::SubscribedTo(chain.label()));
+                    feed_serializer.push(feed_message::TimeSync(now()));
+                    feed_serializer.push(feed_message::BestBlock (
+                        chain.best_block().height,
+                        chain.timestamp(),
+                        chain.average_block_time()
+                    ));
+                    feed_serializer.push(feed_message::BestFinalized (
+                        chain.finalized_block().height,
+                        chain.finalized_block().hash
+                    ));
+                    for (idx, (gid, node)) in node_state.get_nodes_in_chain(chain).enumerate() {
+                        // Send subscription confirmation and chain head before doing all the nodes,
+                        // and continue sending batches of 32 nodes a time over the wire subsequently
+                        if idx % 32 == 0 {
+                            if let Some(bytes) = feed_serializer.finalize() {
+                                let _ = feed_channel.send(ToFeedWebsocket::Bytes(bytes)).await;
+                            }
+                        }
+                        feed_serializer.push(feed_message::AddedNode(gid, node));
+                        feed_serializer.push(feed_message::FinalizedBlock(
+                            gid,
+                            node.finalized().height,
+                            node.finalized().hash,
+                        ));
+                        if node.stale() {
+                            feed_serializer.push(feed_message::StaleNode(gid));
+                        }
+                    }
+                    if let Some(bytes) = feed_serializer.into_finalized() {
+                        let _ = feed_channel.send(ToFeedWebsocket::Bytes(bytes)).await;
+                    }
+
+                    // Actually make a note of the new chain subsciption:
+                    feed_conn_id_to_chain.insert(feed_conn_id, chain.label().into());
+                    chain_to_feed_conn_ids.entry(chain.label().into()).or_default().insert(feed_conn_id);
+                },
+                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::SendFinality) => {
+                    feed_conn_id_finality.insert(feed_conn_id);
+                },
+                ToAggregator::FromFeedWebsocket(feed_conn_id, FromFeedWebsocket::NoMoreFinality) => {
                     feed_conn_id_finality.remove(&feed_conn_id);
-                    // TODO: Do we care about the chain here?
                 },
                 ToAggregator::FromShardWebsocket(shard_conn_id, FromShardWebsocket::Initialize { channel }) => {
                     shard_channels.insert(shard_conn_id, channel);
                 },
-                ToAggregator::FromShardWebsocket(shard_conn_id, FromShardWebsocket::Add { local_id, ip, node }) => {
+                ToAggregator::FromShardWebsocket(shard_conn_id, FromShardWebsocket::Add { local_id, ip, node, genesis_hash }) => {
-                    let global_node_id = to_global_node_id.assign_id((shard_conn_id, local_id));
+                    // Get globalId from add_node and store that against shard/local_id.
 
                     // TODO: node_state.add_node. Every feed should know about node count changes.
                 },
@@ -201,11 +282,47 @@ impl Aggregator {
                     }
                 },
                 ToAggregator::FromShardWebsocket(shard_conn_id, FromShardWebsocket::Update { local_id, payload }) => {
+                    // TODO: Fill this all in...
                     let global_node_id = match to_global_node_id.get_id(&(shard_conn_id, local_id)) {
                         Some(id) => id,
                         None => continue
                     };
 
+                    if let Some(block) = payload.best_block() {
+
+                    }
+
+                    match payload {
+                        node::Payload::SystemInterval(system_interval) => {
+
+                        },
+                        node::Payload::AfgAuthoritySet(_) => {
+
+                        },
+                        node::Payload::AfgFinalized(_) => {
+
+                        },
+                        node::Payload::AfgReceivedPrecommit(_) => {
+
+                        },
+                        node::Payload::AfgReceivedPrevote(_) => {
+
+                        },
+                        // This message should have been handled before the payload made it this far:
+                        node::Payload::SystemConnected(_) => {
+                            unreachable!("SystemConnected message seen in Telemetry Core, but should have been handled in shard");
+                        },
+                        // The following messages aren't handled at the moment. List them explicitly so
+                        // that we have to make an explicit choice for any new messages:
+                        node::Payload::BlockImport(_) |
+                        node::Payload::NotifyFinalized(_) |
+                        node::Payload::AfgReceivedCommit(_) |
+                        node::Payload::TxPoolImport |
+                        node::Payload::AfgFinalizedBlocksUpTo |
+                        node::Payload::AuraPreSealedBlock |
+                        node::Payload::PreparedBlockForProposing => {},
+                    }
+
                     // TODO: node_state.update_node, then handle returned diffs
                 },
             }

backend/telemetry/src/feed_message.rs

@@ -1,15 +1,14 @@
-//! This module provides the messages that will be
+//! This module provides a way of encoding the various messages that we'll
-//! sent to subscribing feeds.
+//! send to subscribed feeds (browsers).
 
-use serde::ser::{SerializeTuple, Serializer};
 use serde::Serialize;
 use std::mem;
 
-use super::node::Node;
+use crate::state::Node;
 use serde_json::to_writer;
 use common::types::{
     Address, BlockDetails, BlockHash, BlockNumber, NodeHardware, NodeIO, NodeId, NodeStats,
-    Timestamp, NodeDetails,
+    Timestamp
 };
 
 pub trait FeedMessage {
@@ -65,6 +64,8 @@ impl FeedMessageSerializer {
         let _ = to_writer(&mut self.buffer, value);
     }
 
+    /// Return the bytes we've serialized so far and prepare a new buffer. If you're
+    /// finished serializing data, prefer [`FeedMessageSerializer::into_finalized`]
     pub fn finalize(&mut self) -> Option<Vec<u8>> {
         if self.buffer.is_empty() {
             return None;
@@ -76,6 +77,16 @@ impl FeedMessageSerializer {
 
         Some(bytes)
     }
+
+    /// Return the bytes that we've serialized so far, consuming the serializer.
+    pub fn into_finalized(mut self) -> Option<Vec<u8>> {
+        if self.buffer.is_empty() {
+            return None;
+        }
+
+        self.buffer.push(b']');
+        Some(self.buffer)
+    }
 }
 
 macro_rules! actions {

backend/telemetry/src/main.rs

@@ -1,5 +1,6 @@
 mod aggregator;
 mod state;
+mod feed_message;
 
 use std::net::SocketAddr;
 use std::str::FromStr;
@@ -193,8 +194,8 @@ async fn handle_shard_websocket_connection<S>(mut websocket: ws::WebSocket, mut
 
                 // Convert and send to the aggregator:
                 let aggregator_msg = match msg {
-                    internal_messages::FromShardAggregator::AddNode { ip, node, local_id } => {
+                    internal_messages::FromShardAggregator::AddNode { ip, node, local_id, genesis_hash } => {
-                        FromShardWebsocket::Add { ip, node, local_id }
+                        FromShardWebsocket::Add { ip, node, genesis_hash, local_id }
                     },
                     internal_messages::FromShardAggregator::UpdateNode { payload, local_id } => {
                         FromShardWebsocket::Update { local_id, payload }
@@ -241,7 +242,13 @@ async fn handle_feed_websocket_connection<S>(mut websocket: ws::WebSocket, mut t
                     None => break
                 };
 
-                println!("TODO: encode message and send down feed websocket: {:?}", msg);
+                // Send messages to the client (currently the only message is
+                // pre-serialized bytes that we send as binary):
+                match msg {
+                    ToFeedWebsocket::Bytes(bytes) => {
+                        let _ = websocket.send(ws::Message::binary(bytes)).await;
+                    }
+                }
             }
             // FRONTEND -> AGGREGATOR
             msg = websocket.next() => {

backend/telemetry/src/state/chain.rs

@@ -1,3 +1,59 @@
-pub struct Chain {
+use std::sync::Arc;
+use std::collections::{ HashSet, HashMap };
+use common::types::{ BlockHash };
+use common::internal_messages::{ GlobalId };
+use super::node::Node;
+use common::types::{Block, NodeDetails, NodeId, NodeLocation, Timestamp};
+use common::util::{now, DenseMap, NumStats};
+use common::node::Payload;
+use std::iter::IntoIterator;
 
+pub type ChainId = usize;
+pub type Label = Arc<str>;
+
+pub struct Chain {
+    /// Label of this chain, along with count of nodes that use this label
+    label: (Label, usize),
+    /// Chain genesis hash
+    genesis_hash: BlockHash,
+    /// Set of nodes that are in this chain
+    nodes: HashSet<GlobalId>,
+    /// Best block
+    best: Block,
+    /// Finalized block
+    finalized: Block,
+    /// Block times history, stored so we can calculate averages
+    block_times: NumStats<u64>,
+    /// Calculated average block time
+    average_block_time: Option<u64>,
+    /// When the best block first arrived
+    timestamp: Option<Timestamp>,
+    /// Some nodes might manifest a different label, note them here
+    labels: HashMap<Label, usize>,
+    /// How many nodes are allowed in this chain
+    max_nodes: usize
+}
+
+impl Chain {
+    pub fn label(&self) -> &str {
+        &self.label.0
+    }
+    pub fn node_count(&self) -> usize {
+        self.nodes.len()
+    }
+    pub fn node_ids(&self) -> impl Iterator<Item=GlobalId> + '_ {
+        self.nodes.iter().copied()
+    }
+    pub fn best_block(&self) -> &Block {
+        &self.best
+    }
+    pub fn timestamp(&self) -> Timestamp {
+        self.timestamp.unwrap_or(0)
+    }
+    pub fn average_block_time(&self) -> Option<u64> {
+        self.average_block_time
+    }
+    pub fn finalized_block(&self) -> &Block {
+        &self.finalized
+    }
 }

backend/telemetry/src/state/mod.rs

@@ -1,7 +1,9 @@
 mod node;
 mod chain;
-mod feed_message;
+// mod feed_message;
+// mod diff;
 
 mod state;
 
 pub use state::State;
+pub use node::Node;

backend/telemetry/src/state/state.rs

@@ -1,14 +1,129 @@
-use super::chain::Chain;
+use std::sync::Arc;
-use std::collections::HashMap;
+use std::collections::{ HashSet, HashMap };
+use common::types::{ BlockHash };
+use common::internal_messages::{ GlobalId };
+use super::node::Node;
+use once_cell::sync::Lazy;
+use common::types::{Block, NodeDetails, NodeId, NodeLocation, Timestamp};
+use common::util::{now, DenseMap, NumStats};
+use common::node::Payload;
+use std::iter::IntoIterator;
 
+use super::chain::Chain;
+
+pub type ChainId = usize;
+pub type Label = Arc<str>;
+
+/// Our state constains node and chain information
 pub struct State {
-    chains: HashMap<Box<str>, Chain>
+    chains: DenseMap<Chain>,
+    nodes: HashMap<GlobalId, Node>,
+    chains_by_genesis_hash: HashMap<BlockHash, ChainId>,
+    chains_by_label: HashMap<Label, ChainId>,
+    /// Denylist for networks we do not want to allow connecting.
+    denylist: HashSet<String>,
+}
+
+/// Labels of chains we consider "first party". These chains allow any
+/// number of nodes to connect.
+static FIRST_PARTY_NETWORKS: Lazy<HashSet<&'static str>> = Lazy::new(|| {
+    let mut set = HashSet::new();
+    set.insert("Polkadot");
+    set.insert("Kusama");
+    set.insert("Westend");
+    set.insert("Rococo");
+    set
+});
+
+/// Max number of nodes allowed to connect to the telemetry server.
+const THIRD_PARTY_NETWORKS_MAX_NODES: usize = 500;
+
+/// Adding a node to a chain leads to this result:
+pub enum AddNodeResult {
+    /// The chain is on the "deny list", so we can't add the node
+    ChainOnDenyList,
+    /// The chain is over quota (too many nodes connected), so can't add the node
+    ChainOverQuota,
+    /// The node was added to the chain
+    NodeAddedToChain(NodeAddedToChain)
+}
+
+pub struct NodeAddedToChain {
+    /// The label for the chain (which may have changed as a result of adding the node):
+    chain_label: Arc<str>,
+    /// Has the chain label been updated?
+    has_chain_label_changed: bool,
+    // How many nodes now exist in the chain?
+    chain_node_count: usize
+}
+
+pub struct RemoveNodeResult {
+    /// How many nodes remain on the chain (0 if the chain was removed):
+    chain_node_count: usize
 }
 
 impl State {
-    pub fn new() -> State {
+    pub fn new<T: IntoIterator<Item=String>>(denylist: T) -> State {
         State {
-            chains: HashMap::new()
+            chains: DenseMap::new(),
+            nodes: HashMap::new(),
+            chains_by_genesis_hash: HashMap::new(),
+            chains_by_label: HashMap::new(),
+            denylist: denylist.into_iter().collect()
         }
     }
+
+    pub fn iter_chains(&self) -> impl Iterator<Item=&Chain> {
+        self.chains
+            .iter()
+            .map(|(_,chain)| chain)
+    }
+
+    pub fn get_chain_by_label(&self, label: &str) -> Option<&Chain> {
+        self.chains_by_label
+            .get(label)
+            .and_then(|chain_id| self.chains.get(*chain_id))
+    }
+
+    pub fn get_nodes_in_chain<'s>(&'s self, chain: &'s Chain) -> impl Iterator<Item=(GlobalId,&Node)> {
+        chain.node_ids()
+            .filter_map(move |id| self.nodes.get(&id).map(|node| (id, node)))
+    }
+
+    // /// Add a new node to our state.
+    // pub fn add_node(&mut self, id: GlobalId, genesis_hash: BlockHash, node: &NodeDetails) -> AddNodeResult {
+    //     if self.denylist.contains(&*node.chain) {
+    //         return AddNodeResult::ChainOnDenyList;
+    //     }
+    //     let chain_id = self.chains.get_or_create(genesis_hash, &node.chain);
+
+    //     return Ok(())
+    // }
+
+    // /// Remove a node from our state.
+    // pub fn remove_node(&mut self, id: GlobalId) -> RemoveNodeResult {
+
+    // }
+
+    // /// Update a node with new data. This needs breaking down into parts so
+    // /// that we can emit a useful result in each case to inform the aggregator
+    // /// what messages it needs to emit.
+    // pub fn update_node(&mut self, id: GlobalId, payload: Payload) {
+
+    // }
+
+    // fn get_or_create_chain(genesis_hash: BlockHash, chain: &str) -> ChainId {
+
+    // }
+}
+
+/// First party networks (Polkadot, Kusama etc) are allowed any number of nodes.
+/// Third party networks are allowed `THIRD_PARTY_NETWORKS_MAX_NODES` nodes and
+/// no more.
+fn max_nodes(label: &str) -> usize {
+    if FIRST_PARTY_NETWORKS.contains(label) {
+        usize::MAX
+    } else {
+        THIRD_PARTY_NETWORKS_MAX_NODES
+    }
 }