Clear memory after handling each new block (#66)

lib/cosmos-node-subscription.js

@@ -39,6 +39,8 @@ class CosmosNodeSubscription {
         publishUserTransactionAdded(this.network.id, address, tx)
       })
     })
+
+    this.cosmosAPI.clearMemory()
   }
 }
 

lib/helpers/PerBlockCacheDataSource.js

@@ -12,6 +12,15 @@ class PerBlockCacheDataSource extends RESTDataSource {
   cacheKeyFor(request) {
     return `${request.url}_${this.blockHeight}`
   }
+
+  clearMemory() {    
+    // The memoizedResults map used for caching requests is never
+    // cleared automatically. The RESTDataSource assumes it will be
+    // created a new for each request.
+    // We maintain instances for parsing new block events on a network,
+    // so we have a need to call this manually.
+    this.memoizedResults.clear()
+  }
 }
 
 module.exports = {