Add randomness to pallet-collator-assignment (#267)

* Add randomness to pallet-collator-assignment

* Mock randomness inherent in tests

* Do not shuffle collators if seed is 0

* Merge the functions to add and fill new container chains into one

* Rotate collators according to config param

* Use per-block randomness instead of per-epoch randomness

* Dont check collator2002-01 dbpath

Because a different collator may be assigned to container 2002

* Add zombie_tanssi_rotation test suite

* Unit test collator assignment rotation

* Fix integration test by killing storage value

* Rename para-rotation suite to avoid moonwall bug

* Increase zombienet test timeout

* Mix subject with relay randomness, and fix bug all seeds starting with 1

There was a bug because we tried to read an Option<Hash> as a Hash, and
this results in the first byte of the [u8; 32] being always 1, which is
the marker for "Some"

* Fix collators rotating 1 block too early

* Add event CollatorAssignment::NewPendingAssignment

* Fix tests after 1.1.0 upgrade

* Make full_rotation_period configurable, defined in pallet_configuration

* Use fast_or_prod macro to set full_rotation_period = 5 for tests

* Store randomness from previous relay block in pallet storage

Because since #288 collator rotation is handled in on_initialize, and we
can only read the relay randomness after the set_validation_data
inherent, which happens after on_initialize.

The solution is to read the randomness on the on_finalize hook of the
previous block, store it in pallet_collator_assignment, and delete it
when reading it.

* Change para-rotation test to rotate every 5 sessions instead of every 1

Rotating every session does not leave enough time for collators to
detect their assignment, and some tests result in timeout

* Rewrite migration using get_raw and put_raw

* Rotation period of 0 disables rotation

.github/workflows/release.yml

@@ -440,6 +440,61 @@ jobs:
                   name: logs
                   path: logs
 
+    zombienet-tests-rotation:
+        runs-on: self-hosted
+        needs: ["set-tags", "build"]
+        steps:
+            - name: Checkout
+              uses: actions/checkout@v3
+              with:
+                  ref: ${{ needs.set-tags.outputs.git_ref }}
+
+            - name: Pnpm
+              uses: pnpm/action-setup@v2
+              with:
+                  version: 8
+
+            - name: Setup Node
+              uses: actions/setup-node@v3
+              with:
+                  node-version: 20.x
+                  cache: "pnpm"
+
+            - name: "Download binaries"
+              uses: actions/[email protected]
+              with:
+                  name: binaries
+                  path: target/release
+
+            - name: "Run zombie test"
+              run: |
+                  chmod uog+x target/release/tanssi-node
+                  chmod uog+x target/release/container-chain-template-simple-node
+                  chmod uog+x target/release/container-chain-template-frontier-node
+
+                  cd test
+                  pnpm install
+
+                  ## Run tests
+
+                  pnpm moonwall test zombie_tanssi_rotation
+
+            - name: "Gather zombie logs"
+              if: failure()
+              run: |
+                  ls -ltr /tmp
+                  latest_zombie_dir=$(find /tmp -type d -iname "*zombie*" -printf '%T@ %p\n' | sort -n | tail -1 | cut -f2- -d" ")
+                  logs_dir="logs"
+                  mkdir -p "$logs_dir"
+                  find "$latest_zombie_dir" -type f -name "*.log" -exec cp {} "$logs_dir" \;
+
+            - name: "Upload zombie logs"
+              if: failure()
+              uses: actions/[email protected]
+              with:
+                  name: logs-rotation
+                  path: logs
+
     zombienet-tests-warp-sync:
         runs-on: ubuntu-latest
         needs: ["set-tags", "build"]

Cargo.toml

@@ -186,6 +186,7 @@ cumulus-client-pov-recovery = { git = "https://github.com/moondance-labs/polkado
 cumulus-client-service = { git = "https://github.com/moondance-labs/polkadot-sdk", branch = "tanssi-polkadot-v1.1.0", default-features = false }
 cumulus-primitives-parachain-inherent = { git = "https://github.com/moondance-labs/polkadot-sdk", branch = "tanssi-polkadot-v1.1.0", default-features = false }
 cumulus-relay-chain-interface = { git = "https://github.com/moondance-labs/polkadot-sdk", branch = "tanssi-polkadot-v1.1.0", default-features = false }
+cumulus-test-relay-sproof-builder = { git = "https://github.com/moondance-labs/polkadot-sdk", branch = "tanssi-polkadot-v1.1.0", default-features = false }
 xcm-emulator = { git = "https://github.com/moondance-labs/polkadot-sdk", branch = "tanssi-polkadot-v1.1.0", default-features = false }
 
 # Frontier (wasm)
@@ -220,6 +221,7 @@ hex-literal = { version = "0.3.4" }
 log = { version = "0.4.17", default-features = false }
 serde = { version = "1.0.152", default-features = false }
 smallvec = "1.10.0"
+rand_chacha = { version = "0.3.1", default-features = false }
 
 # General (client)
 async-io = "1.3"

node/src/chain_spec.rs

@@ -17,8 +17,8 @@
 use {
     cumulus_primitives_core::ParaId,
     dancebox_runtime::{
-        AccountId, MaintenanceModeConfig, MigrationsConfig, PolkadotXcmConfig, RegistrarConfig,
-        Signature, SudoConfig,
+        prod_or_fast, AccountId, MaintenanceModeConfig, MigrationsConfig, PolkadotXcmConfig,
+        RegistrarConfig, Signature, SudoConfig,
     },
     nimbus_primitives::NimbusId,
     pallet_configuration::HostConfiguration,
@@ -195,6 +195,7 @@ pub fn development_config(
                         min_orchestrator_collators: 1u32,
                         max_orchestrator_collators: 1u32,
                         collators_per_container: 2u32,
+                        full_rotation_period: prod_or_fast!(24u32, 5u32),
                     },
                     ..Default::default()
                 },
@@ -259,6 +260,7 @@ pub fn local_dancebox_config(
                         min_orchestrator_collators: 2u32,
                         max_orchestrator_collators: 5u32,
                         collators_per_container: 2u32,
+                        full_rotation_period: prod_or_fast!(24u32, 5u32),
                     },
                     ..Default::default()
                 },

pallets/authority-assignment/src/mock.rs

@@ -140,6 +140,7 @@ pub fn run_to_block(n: u64) {
     let old_block_number = System::block_number();
 
     for x in (old_block_number + 1)..=n {
+        System::reset_events();
         System::set_block_number(x);
 
         if x % SESSION_LEN == 1 {

pallets/collator-assignment/Cargo.toml

@@ -21,7 +21,8 @@ sp-std = { workspace = true }
 tp-collator-assignment = { workspace = true }
 tp-traits = { workspace = true }
 frame-benchmarking = { workspace = true }
-rand = { workspace = true, optional = true }
+rand = { workspace = true }
+rand_chacha = { workspace = true }
 
 [dev-dependencies]
 sp-io = { workspace = true }
@@ -44,7 +45,6 @@ runtime-benchmarks = [
 	"frame-benchmarking/runtime-benchmarks",
 	"frame-support/runtime-benchmarks",
 	"frame-system/runtime-benchmarks",
-	"rand",
 	"tp-traits/runtime-benchmarks",
 ]
 try-runtime = [ "frame-support/try-runtime" ]

pallets/collator-assignment/src/benchmarking.rs

@@ -47,6 +47,14 @@ fn invulnerables<T: Config + frame_system::Config>(count: u32, seed: u32) -> Vec
     invulnerables
 }
 
+fn assert_last_event<T: Config>(generic_event: <T as Config>::RuntimeEvent) {
+    let events = frame_system::Pallet::<T>::events();
+    let system_event: <T as frame_system::Config>::RuntimeEvent = generic_event.into();
+    // compare to the last event record
+    let EventRecord { event, .. } = &events[events.len() - 1];
+    assert_eq!(event, &system_event);
+}
+
 #[benchmarks]
 mod benchmarks {
     use super::*;
@@ -75,6 +83,9 @@ mod benchmarks {
             container_chains: BTreeMap::from_iter(old_container_chains),
         };
         <CollatorContainerChain<T>>::put(&old_assigned);
+        // Do not use [0; 32] because that seed will not shuffle the list of collators
+        let random_seed = [1; 32];
+        <Randomness<T>>::put(random_seed);
 
         #[block]
         {
@@ -89,6 +100,16 @@ mod benchmarks {
             0
         );
 
+        // Worst case is `full_rotation: false` because it needs to check the previous assignment
+        assert_last_event::<T>(
+            Event::NewPendingAssignment {
+                random_seed,
+                full_rotation: false,
+                target_session: T::SessionIndex::from(1u32),
+            }
+            .into(),
+        );
+
         Ok(())
     }