dfinity · aterga · Feb 17, 2025 · Jan 23, 2025 · Jan 24, 2025 · Jan 24, 2025
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -346,6 +346,7 @@ members = [
     "rs/sns/swap",
     "rs/sns/swap/proto_library",
     "rs/sns/test_utils",
+    "rs/sns/testing",
     "rs/starter",
     "rs/state_manager",
     "rs/state_machine_tests",

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 
 ### Added
+- The function `PocketIc::try_get_controllers` which gets the controllers of a canister but doesn't panic if the target canister
+  doesn't exist.
 - The function `PocketIcBuilder::with_bitcoind_addrs` to specify multiple addresses and ports at which `bitcoind` processes are listening.
 - The function `PocketIc::query_call_with_effective_principal` for making generic query calls (including management canister query calls).
 - The function `PocketIc::ingress_status` to fetch the status of an update call submitted through an ingress message.

@@ -70,7 +70,7 @@ use candid::{
     Principal,
 };
 use ic_transport_types::SubnetMetrics;
-use reqwest::Url;
+use reqwest::{StatusCode, Url};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use slog::Level;
@@ -649,6 +649,16 @@ impl PocketIc {
         runtime.block_on(async { self.pocket_ic.get_controllers(canister_id).await })
     }
 
+    /// Get the controllers of a canister.
+    #[instrument(ret, skip(self), fields(instance_id=self.pocket_ic.instance_id, canister_id = %canister_id.to_string()))]
+    pub fn try_get_controllers(
+        &self,
+        canister_id: CanisterId,
+    ) -> Result<Vec<Principal>, (StatusCode, String)> {
+        let runtime = self.runtime.clone();
+        runtime.block_on(async { self.pocket_ic.try_get_controllers(canister_id).await })
+    }
+
     /// Get the current cycles balance of a canister.
     #[instrument(ret, skip(self), fields(instance_id=self.pocket_ic.instance_id, canister_id = %canister_id.to_string()))]
     pub fn cycle_balance(&self, canister_id: CanisterId) -> u128 {

@@ -519,16 +519,25 @@ impl PocketIc {
     /// Panics if the canister does not exist.
     #[instrument(ret, skip(self), fields(instance_id=self.instance_id, canister_id = %canister_id.to_string()))]
     pub async fn get_controllers(&self, canister_id: CanisterId) -> Vec<Principal> {
+        self.try_get_controllers(canister_id).await.unwrap()
+    }
+
+    /// Get the controllers of a canister.
+    #[instrument(ret, skip(self), fields(instance_id=self.instance_id, canister_id = %canister_id.to_string()))]
+    pub async fn try_get_controllers(
+        &self,
+        canister_id: CanisterId,
+    ) -> Result<Vec<Principal>, (StatusCode, String)> {
         let endpoint = "read/get_controllers";
-        let result: Vec<RawPrincipalId> = self
-            .post(
+        let result: Result<Vec<RawPrincipalId>, (StatusCode, String)> = self
+            .try_post(
                 endpoint,
                 RawCanisterId {
                     canister_id: canister_id.as_slice().to_vec(),
                 },
             )
             .await;
-        result.into_iter().map(|p| p.into()).collect()
+        result.map(|v| v.into_iter().map(|p| p.into()).collect())
     }
 
     /// Get the current cycles balance of a canister.

@@ -1739,6 +1739,19 @@ fn get_controllers_of_nonexisting_canister() {
     let _ = pic.get_controllers(canister_id);
 }
 
+#[test]
+fn try_get_controllers_of_nonexisting_canister() {
+    let pic = PocketIc::new();
+
+    let canister_id = pic.create_canister();
+    pic.add_cycles(canister_id, 100_000_000_000_000);
+    pic.stop_canister(canister_id, None).unwrap();
+    pic.delete_canister(canister_id, None).unwrap();
+
+    let res = pic.try_get_controllers(canister_id);
+    assert!(res.is_err())
+}
+
 #[test]
 fn test_canister_snapshots() {
     let pic = PocketIc::new();

@@ -6,7 +6,7 @@ use serde_bytes::ByteBuf;
 
 pub mod logs;
 
-#[derive(Debug, CandidType, Deserialize)]
+#[derive(Clone, Debug, CandidType, Deserialize)]
 pub struct InitArg {
     pub ledger_id: Principal,
 }

@@ -148,7 +148,11 @@ impl CallCanisters for PocketIcAgent<'_> {
     ) -> Result<CanisterInfo, Self::Error> {
         let canister_id = canister_id.into();
 
-        let controllers = self.pocket_ic.get_controllers(canister_id).await;
+        let controllers = self
+            .pocket_ic
+            .try_get_controllers(canister_id)
+            .await
+            .unwrap_or(vec![]);
 
         let Some(controller) = controllers.into_iter().last() else {
             return Err(Self::Error::BlackHole);