feat: asset canister exposes state info

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 # UNRELEASED
 
+## Dependencies
+
+### Frontend canister
+
+#### feat: `get_state_info` returns last asset change timestamp and state hash
+
+- Module hash: 15a6366a4823baf994f314a55ddbdda333dff11cbcc5114caebfe444e5eae3b6
+- https://github.com/dfinity/sdk/pull/4434
+
 # 0.30.1
 
 ### feat: asset sync now prints the target asset canister state hash in `--verbose` mode

src/canisters/frontend/ic-certified-assets/assets.did

@@ -123,6 +123,11 @@ type ConfigureArguments = record {
   max_bytes: opt opt nat64;
 };
 
+type StateInfo = record {
+  last_state_update_timestamp: nat64;
+  state_hash: opt text;
+};
+
 type Permission = variant {
   Commit;
   ManagePermissions;
@@ -224,6 +229,9 @@ service: (asset_canister_args: opt AssetCanisterArgs) -> {
   // Compute a hash over the canister content.  Call until it returns Some(hash).
   compute_state_hash: () -> (opt text);
 
+  // Get information about the current state of the canister
+  get_state_info: () -> (StateInfo) query;
+
   // Delete a batch that has been created, or proposed for commit, but not yet committed
   delete_batch: (DeleteBatchArguments) -> ();
 

src/canisters/frontend/ic-certified-assets/src/lib.rs

@@ -236,6 +236,10 @@ pub fn compute_state_hash() -> Option<String> {
     with_state_mut(|s| s.compute_state_hash(&system_context))
 }
 
+pub fn get_state_info() -> StateInfo {
+    with_state(|s| s.get_state_info())
+}
+
 pub fn commit_proposed_batch(arg: CommitProposedBatchArguments) {
     let system_context = SystemContext::new();
 
@@ -656,6 +660,12 @@ macro_rules! export_canister_methods {
             $crate::compute_state_hash()
         }
 
+        #[$crate::ic_certified_assets_query]
+        #[$crate::ic_certified_assets_candid_method(query)]
+        fn get_state_info() -> types::StateInfo {
+            $crate::get_state_info()
+        }
+
         #[$crate::ic_certified_assets_update(guard = "__ic_certified_assets_can_commit")]
         #[$crate::ic_certified_assets_candid_method(update)]
         fn commit_proposed_batch(arg: types::CommitProposedBatchArguments) {

src/canisters/frontend/ic-certified-assets/src/state_machine/mod.rs

@@ -911,6 +911,19 @@ impl State {
         }
     }
 
+    pub fn get_state_info(&self) -> StateInfo {
+        let state_hash =
+            if let Some(EvidenceComputation::Computed(evidence)) = &self.state_hash_computation {
+                Some(hex::encode(evidence.as_slice()))
+            } else {
+                None
+            };
+        StateInfo {
+            last_state_update_timestamp: self.last_state_update_timestamp_ns,
+            state_hash,
+        }
+    }
+
     pub fn delete_batch(&mut self, arg: DeleteBatchArguments) -> Result<(), String> {
         if self.batches.remove(&arg.batch_id).is_none() {
             return Err("batch not found".to_string());

src/canisters/frontend/ic-certified-assets/src/types.rs

@@ -24,6 +24,12 @@ pub struct ConfigurationResponse {
     pub max_bytes: Option<u64>,
 }
 
+#[derive(Clone, Debug, CandidType, Deserialize)]
+pub struct StateInfo {
+    pub last_state_update_timestamp: u64,
+    pub state_hash: Option<String>,
+}
+
 #[derive(Clone, Debug, CandidType, Deserialize)]
 pub struct CreateAssetArguments {
     pub key: AssetKey,

src/distributed/assetstorage.did

@@ -123,6 +123,11 @@ type ConfigureArguments = record {
   max_bytes: opt opt nat64;
 };
 
+type StateInfo = record {
+  last_state_update_timestamp: nat64;
+  state_hash: opt text;
+};
+
 type Permission = variant {
   Commit;
   ManagePermissions;
@@ -224,6 +229,9 @@ service: (asset_canister_args: opt AssetCanisterArgs) -> {
   // Compute a hash over the canister content.  Call until it returns Some(hash).
   compute_state_hash: () -> (opt text);
 
+  // Get information about the current state of the canister
+  get_state_info: () -> (StateInfo) query;
+
   // Delete a batch that has been created, or proposed for commit, but not yet committed
   delete_batch: (DeleteBatchArguments) -> ();