fix(sdk): disable provider polling and correctly check done for past …

…events (UMAprotocol#3833)

Signed-off-by: David <[email protected]>

packages/sdk/src/oracle/services/statemachines/fetchPastEvents.ts

@@ -35,7 +35,7 @@ export function Handlers(store: Store): GenericHandlers<Params, Memory> {
       // we want to move start block closer to endblock to reduce the range until it stops erroring. These range functions
       // will do that for us.
       const rangeState = memory.state || rangeStart({ startBlock, endBlock });
-      const { currentStart, currentEnd, done } = rangeState;
+      const { currentStart, currentEnd } = rangeState;
 
       try {
         // this just queries events between start and end
@@ -54,11 +54,11 @@ export function Handlers(store: Store): GenericHandlers<Params, Memory> {
         // the provider threw an error so we will reduce our range by moving startblock closer to endblock next iteration
         memory.state = rangeFailureDescending(rangeState);
       }
-      // the range functions will tell us when we have successfully queried the entire range of blocks.
-      if (done) return "done";
       memory.iterations++;
+      // the range functions will tell us when we have successfully queried the entire range of blocks.
+      if (memory?.state?.done) return "done";
       // sleep to let other contexts run, but just resume right after.
-      return ctx.sleep(10);
+      return ctx.sleep(100);
     },
   };
 }

packages/sdk/src/oracle/store/write.ts

@@ -114,8 +114,15 @@ export class Services {
   constructor(private state: Partial<state.ChainServices>) {}
   provider(rpcUrls: string[]): void {
     if (this.state?.provider) return;
-    const providers = rpcUrls.map((url) => ethers.getDefaultProvider(url));
+    const providers = rpcUrls.map((url) => {
+      const provider = ethers.getDefaultProvider(url);
+      // turn off all polling, we will poll manually
+      provider.polling = false;
+      return provider;
+    });
     this.state.provider = new ethers.providers.FallbackProvider(providers, 1);
+    // turn off all polling, we will poll manually
+    this.state.provider.polling = false;
   }
   erc20s(address: string): void {
     if (!this.state?.provider) return;