fix(cluster): listing api is fixed; limit guard is added

bucket/ddc_bucket/cluster/messages.rs

@@ -434,11 +434,14 @@ impl DdcBucket {
         filter_manager_id: Option<AccountId>,
     ) -> (Vec<ClusterInfo>, u32) {
         let mut clusters = Vec::with_capacity(limit as usize);
-        for cluster_id in offset..offset + limit {
-            let cluster = match self.clusters.clusters.get(cluster_id) {
+        for idx in offset..offset + limit {
+            let cluster_id = match self.clusters.clusters_ids.get(idx as usize) {
                 None => break, // No more items, stop.
-                Some(cluster) => cluster,
+                Some(cluster_id) => *cluster_id,
             };
+
+            let cluster = self.clusters.clusters.get(cluster_id).unwrap();
+
             // Apply the filter if given.
             if let Some(manager_id) = filter_manager_id {
                 if manager_id != cluster.manager_id {
@@ -462,7 +465,10 @@ impl DdcBucket {
 
             clusters.push(cluster_info);
         }
-        (clusters, self.clusters.next_cluster_id)
+        (
+            clusters,
+            self.clusters.clusters_ids.len().try_into().unwrap(),
+        )
     }
 
     pub fn message_cluster_distribute_revenues(&mut self, cluster_id: ClusterId) -> Result<()> {

bucket/ddc_bucket/cluster/store.rs

@@ -2,29 +2,40 @@
 
 use super::entity::{Cluster, ClusterId, ClusterParams};
 use crate::ddc_bucket::{AccountId, Error::*, Resource, Result};
+use ink_prelude::vec::Vec;
 use ink_storage::traits::{SpreadAllocate, SpreadLayout};
 use ink_storage::Mapping;
 
 #[derive(SpreadAllocate, SpreadLayout, Default)]
 #[cfg_attr(feature = "std", derive(ink_storage::traits::StorageLayout, Debug))]
 pub struct ClusterStore {
-    pub next_cluster_id: u32,
+    pub next_cluster_id: ClusterId,
     pub clusters: Mapping<ClusterId, Cluster>,
+    pub clusters_ids: Vec<ClusterId>,
 }
 
+// https://use.ink/datastructures/storage-layout#packed-vs-non-packed-layout
+// There is a buffer with only limited capacity (around 16KB in the default configuration) available.
+pub const MAX_CLUSTERS_LEN_IN_VEC: usize = 3900;
+
 impl ClusterStore {
     pub fn create(
         &mut self,
         manager_id: AccountId,
         cluster_params: ClusterParams,
         resource_per_v_node: Resource,
     ) -> Result<ClusterId> {
+        if self.clusters_ids.len() + 1 > MAX_CLUSTERS_LEN_IN_VEC {
+            return Err(NodesSizeExceedsLimit);
+        }
+
         let cluster_id = self.next_cluster_id;
         self.next_cluster_id = self.next_cluster_id + 1;
 
         let cluster = Cluster::new(manager_id, cluster_params, resource_per_v_node)?;
 
         self.clusters.insert(&cluster_id, &cluster);
+        self.clusters_ids.push(cluster_id);
         Ok(cluster_id)
     }
 
@@ -43,5 +54,8 @@ impl ClusterStore {
 
     pub fn remove(&mut self, cluster_id: ClusterId) {
         self.clusters.remove(cluster_id);
+        if let Some(pos) = self.clusters_ids.iter().position(|x| *x == cluster_id) {
+            self.clusters_ids.remove(pos);
+        };
     }
 }