Distribution feature for the storage pallet.

node/src/chain_spec/mod.rs

@@ -33,10 +33,10 @@ use sp_runtime::Perbill;
 use node_runtime::{
     membership, wasm_binary_unwrap, AuthorityDiscoveryConfig, BabeConfig, Balance, BalancesConfig,
     ContentDirectoryConfig, ContentDirectoryWorkingGroupConfig, ContentWorkingGroupConfig,
-    CouncilConfig, CouncilElectionConfig, ElectionParameters, ForumConfig, GrandpaConfig,
-    ImOnlineConfig, MembersConfig, Moment, ProposalsCodexConfig, SessionConfig, SessionKeys,
-    Signature, StakerStatus, StakingConfig, StorageWorkingGroupConfig, SudoConfig, SystemConfig,
-    VersionedStoreConfig, VersionedStorePermissionsConfig, DAYS,
+    CouncilConfig, CouncilElectionConfig, DistributionWorkingGroupConfig, ElectionParameters,
+    ForumConfig, GrandpaConfig, ImOnlineConfig, MembersConfig, Moment, ProposalsCodexConfig,
+    SessionConfig, SessionKeys, Signature, StakerStatus, StakingConfig, StorageWorkingGroupConfig,
+    SudoConfig, SystemConfig, VersionedStoreConfig, VersionedStorePermissionsConfig, DAYS,
 };
 
 // Exported to be used by chain-spec-builder
@@ -319,6 +319,13 @@ pub fn testnet_genesis(
             worker_application_human_readable_text_constraint: default_text_constraint,
             worker_exit_rationale_text_constraint: default_text_constraint,
         }),
+        working_group_Instance4: Some(DistributionWorkingGroupConfig {
+            phantom: Default::default(),
+            working_group_mint_capacity: 0,
+            opening_human_readable_text_constraint: default_text_constraint,
+            worker_application_human_readable_text_constraint: default_text_constraint,
+            worker_exit_rationale_text_constraint: default_text_constraint,
+        }),
         content_directory: Some({
             ContentDirectoryConfig {
                 class_by_id: vec![],

runtime-modules/common/src/working_group.rs

@@ -20,4 +20,7 @@ pub enum WorkingGroup {
 
     /// Storage working group: working_group::Instance3.
     Content = 3isize,
+
+    /// Distribution working group: working_group::Instance4.
+    Distribution = 4isize,
 }

runtime-modules/storage/src/distribution_bucket_picker.rs

@@ -0,0 +1,94 @@
+#![warn(missing_docs)]
+
+use frame_support::traits::Randomness;
+use sp_arithmetic::traits::Zero;
+use sp_runtime::SaturatedConversion;
+use sp_std::cell::RefCell;
+use sp_std::collections::btree_set::BTreeSet;
+use sp_std::marker::PhantomData;
+use sp_std::rc::Rc;
+use sp_std::vec::Vec;
+
+use crate::{DynamicBagType, Module, Trait};
+
+// Generates distribution bucket IDs to assign to a new dynamic bag.
+pub(crate) struct DistributionBucketPicker<T> {
+    trait_marker: PhantomData<T>,
+}
+
+impl<T: Trait> DistributionBucketPicker<T> {
+    // Get random distribution buckets from distribution bucket families using the dynamic bag
+    // creation policy.
+    pub(crate) fn pick_distribution_buckets(
+        bag_type: DynamicBagType,
+    ) -> BTreeSet<T::DistributionBucketId> {
+        let creation_policy = Module::<T>::get_dynamic_bag_creation_policy(bag_type);
+
+        if creation_policy.no_distribution_buckets_required() {
+            return BTreeSet::new();
+        }
+
+        // Randomness for all bucket family.
+        // let random_seed = RefCell::new(Module::<T>::get_initial_random_seed());
+        let random_seed = Rc::new(RefCell::new(Module::<T>::get_initial_random_seed()));
+
+        creation_policy
+            .families
+            .iter()
+            .filter_map(|(family_id, bucket_num)| {
+                Module::<T>::ensure_distribution_bucket_family_exists(family_id)
+                    .ok()
+                    .map(|fam| (fam, bucket_num))
+            })
+            .map(|(family, bucket_num)| {
+                let filtered_ids = family
+                    .distribution_buckets
+                    .iter()
+                    .filter_map(|(id, bucket)| bucket.accepting_new_bags.then(|| *id))
+                    .collect::<Vec<_>>();
+
+                (filtered_ids, bucket_num)
+            })
+            .map(|(bucket_ids, bucket_num)| {
+                Self::get_random_distribution_buckets(bucket_ids, *bucket_num, random_seed.clone())
+            })
+            .flatten()
+            .collect::<BTreeSet<_>>()
+    }
+
+    // Get random bucket IDs from the ID collection.
+    pub fn get_random_distribution_buckets(
+        ids: Vec<T::DistributionBucketId>,
+        bucket_number: u32,
+        seed: Rc<RefCell<T::Hash>>, //     seed: RefCell<T::Hash>
+    ) -> BTreeSet<T::DistributionBucketId> {
+        let mut working_ids = ids;
+        let mut result_ids = BTreeSet::default();
+
+        for _ in 0..bucket_number {
+            if working_ids.is_empty() {
+                break;
+            }
+
+            let current_seed = Self::advance_random_seed(seed.clone());
+
+            let upper_bound = working_ids.len() as u64 - 1;
+            let index =
+                Module::<T>::random_index(current_seed.as_ref(), upper_bound).saturated_into();
+            result_ids.insert(working_ids.remove(index));
+        }
+
+        result_ids
+    }
+
+    // Changes the internal seed value of the container and returns new random seed.
+    fn advance_random_seed(seed: Rc<RefCell<T::Hash>>) -> T::Hash {
+        // Cannot create randomness in the initial block (Substrate error).
+        if <frame_system::Module<T>>::block_number() == Zero::zero() {
+            return Module::<T>::get_initial_random_seed();
+        }
+
+        let current_seed = *seed.borrow();
+        seed.replace(T::Randomness::random(current_seed.as_ref()))
+    }
+}