bimap to store global ID mappings: we'll assign them in node state

backend/Cargo.lock

@@ -44,6 +44,12 @@ version = "0.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "904dfeac50f3cdaba28fc6f57fdcddb75f49ed61346676a78c4ffe55877802fd"
 
+[[package]]
+name = "bimap"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50ae17cabbc8a38a1e3e4c1a6a664e9a09672dc14d0896fa8d865d3a5a446b07"
+
 [[package]]
 name = "bincode"
 version = "1.3.3"
@@ -157,6 +163,7 @@ dependencies = [
 name = "common"
 version = "0.1.0"
 dependencies = [
+ "bimap",
  "bincode",
  "bytes",
  "fnv",
@@ -1187,6 +1194,7 @@ name = "telemetry"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "bimap",
  "bincode",
  "common",
  "futures",

backend/common/Cargo.toml

@@ -5,6 +5,7 @@ authors = ["Parity Technologies Ltd. <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
+bimap = "0.6.1"
 bytes = "1.0.1"
 fnv = "1.0.7"
 hex = "0.4.3"

backend/common/src/assign_id.rs

@@ -1,5 +1,6 @@
-use std::{collections::HashMap, hash::Hash};
+use std::hash::Hash;
 use serde::{Serialize,Deserialize};
+use bimap::BiMap;
 
 #[derive(Clone,Copy,Debug,Hash,PartialEq,Eq,Serialize,Deserialize)]
 pub struct Id(usize);
@@ -9,6 +10,11 @@ impl std::convert::From<Id> for usize {
         id.0
     }
 }
+impl std::convert::From<usize> for Id {
+    fn from(n: usize) -> Id {
+        Id(n)
+    }
+}
 
 /// A struct that allows you to assign ID to an arbitrary set of
 /// details (so long as they are Eq+Hash+Clone), and then access
@@ -17,60 +23,45 @@ impl std::convert::From<Id> for usize {
 #[derive(Debug)]
 pub struct AssignId<Details> {
     current_id: Id,
-    from_details: HashMap<Details, Id>,
-    from_id: HashMap<Id, Details>
+    mapping: BiMap<Id, Details>
 }
 
-impl <Details> AssignId<Details> where Details: Eq + Hash + Clone {
+impl <Details> AssignId<Details> where Details: Eq + Hash {
     pub fn new() -> Self {
         Self {
             current_id: Id(0),
-            from_details: HashMap::new(),
-            from_id: HashMap::new()
+            mapping: BiMap::new()
         }
     }
 
     pub fn assign_id(&mut self, details: Details) -> Id {
         let this_id = self.current_id;
         self.current_id.0 += 1;
-
-        self.from_details.insert(details.clone(), this_id);
-        self.from_id.insert(this_id, details);
-
+        self.mapping.insert(this_id, details);
         this_id
     }
 
     pub fn get_details(&mut self, id: Id) -> Option<&Details> {
-        self.from_id.get(&id)
+        self.mapping.get_by_left(&id)
     }
 
     pub fn get_id(&mut self, details: &Details) -> Option<Id> {
-        self.from_details.get(details).map(|id| *id)
+        self.mapping.get_by_right(details).map(|id| *id)
     }
 
     pub fn remove_by_id(&mut self, id: Id) -> Option<Details> {
-        if let Some(details) = self.from_id.remove(&id) {
-            self.from_details.remove(&details);
-            Some(details)
-        } else {
-            None
-        }
+        self.mapping.remove_by_left(&id).map(|(_,details)| details)
     }
 
     pub fn remove_by_details(&mut self, details: &Details) -> Option<Id> {
-        if let Some(id) = self.from_details.remove(&details) {
-            self.from_id.remove(&id);
-            Some(id)
-        } else {
-            None
-        }
+        self.mapping.remove_by_right(&details).map(|(id,_)| id)
     }
 
     pub fn clear(&mut self) {
-        *self = AssignId::new()
+        *self = AssignId::new();
     }
 
     pub fn iter(&self) -> impl Iterator<Item = (Id, &Details)> {
-        self.from_id.iter().map(|(id, details)| (*id, details))
+        self.mapping.iter().map(|(id, details)| (*id, details))
     }
 }

backend/telemetry/Cargo.toml

@@ -6,6 +6,7 @@ edition = "2018"
 
 [dependencies]
 anyhow = "1.0.41"
+bimap = "0.6.1"
 bincode = "1.3.3"
 common = { path = "../common" }
 futures = "0.3.15"

backend/telemetry/src/aggregator.rs

@@ -1,9 +1,9 @@
 use common::{
     internal_messages::{GlobalId, LocalId},
     node,
-    assign_id::AssignId,
     util::now
 };
+use bimap::BiMap;
 use std::{str::FromStr, sync::Arc};
 use std::sync::atomic::AtomicU64;
 use futures::channel::{ mpsc, oneshot };
@@ -155,7 +155,7 @@ impl Aggregator {
 
         // Maintain mappings from the shard connection ID and local ID of messages to a global ID
         // that uniquely identifies nodes in our node state.
-        let mut to_global_node_id = AssignId::new();
+        let mut global_ids: BiMap<GlobalId, (u64, LocalId)> = BiMap::new();
 
         // Keep track of channels to communicate with feeds and shards:
         let mut feed_channels = HashMap::new();
@@ -294,13 +294,13 @@ impl Aggregator {
                     // TODO: node_state.add_node. Every feed should know about node count changes.
                 },
                 ToAggregator::FromShardWebsocket(shard_conn_id, FromShardWebsocket::Remove { local_id }) => {
-                    if let Some(id) = to_global_node_id.remove_by_details(&(shard_conn_id, local_id)) {
+                    if let Some(id) = global_ids.remove_by_right(&(shard_conn_id, local_id)) {
                         // TODO: node_state.remove_node, Every feed should know about node count changes.
                     }
                 },
                 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)) {
+                    let global_node_id = match global_ids.get_by_right(&(shard_conn_id, local_id)) {
                         Some(id) => id,
                         None => continue
                     };