Added migration code for updating vesting contract address

common/cosmwasm-smart-contracts/mixnet-contract/src/msg.rs

@@ -413,4 +413,6 @@ pub enum QueryMsg {
 
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, JsonSchema)]
 #[serde(rename_all = "snake_case")]
-pub struct MigrateMsg {}
+pub struct MigrateMsg {
+    pub vesting_contract_address: String,
+}

contracts/mixnet/src/contract.rs

@@ -467,10 +467,20 @@ pub fn query(
 
 #[entry_point]
 pub fn migrate(
-    _deps: DepsMut<'_>,
+    deps: DepsMut<'_>,
     _env: Env,
-    _msg: MigrateMsg,
+    msg: MigrateMsg,
 ) -> Result<Response, MixnetContractError> {
+    // due to circular dependency on contract addresses (i.e. mixnet contract requiring vesting contract address
+    // and vesting contract requiring the mixnet contract address), if we ever want to deploy any new fresh
+    // environment, one of the contracts will HAVE TO go through a migration
+    if !msg.vesting_contract_address.is_empty() {
+        let mut current_state = mixnet_params_storage::CONTRACT_STATE.load(deps.storage)?;
+        current_state.vesting_contract_address =
+            deps.api.addr_validate(&msg.vesting_contract_address)?;
+        mixnet_params_storage::CONTRACT_STATE.save(deps.storage, &current_state)?;
+    }
+
     Ok(Default::default())
 }