fix(ccip-gateway): Prevent unnecessary calls to the fallback RPC providers (#298)

Author: alainncls

.github/workflows/linea-ccip-gateway-build-publish.yml

@@ -105,7 +105,6 @@ jobs:
             L1_PROVIDER_URL=${{ secrets.L1_PROVIDER_URL_MAINNET }}
             L1_PROVIDER_URL_FALLBACK=${{ secrets.L1_PROVIDER_URL_FALLBACK_MAINNET }}
             L2_PROVIDER_URL=${{ secrets.L2_PROVIDER_URL_MAINNET }}
-            L2_PROVIDER_URL_FALLBACK=${{ secrets.L2_PROVIDER_URL_FALLBACK_MAINNET }}
             L1_ROLLUP_ADDRESS=${{ vars.L1_MAINNET_ROLLUP_ADDRESS }}
             L1_CHAIN_ID=${{ vars.L1_MAINNET_CHAIN_ID }}
             L2_CHAIN_ID=${{ vars.L2_MAINNET_CHAIN_ID }}

packages/linea-ccip-gateway/src/server.ts

@@ -42,6 +42,7 @@ function createFallbackProvider(
       }),
       polling: false,
       stallTimeout: PRIMARY_PROVIDER_TIMEOUT,
+      priority: 1,
       weight: 2,
     },
   ];
@@ -53,6 +54,7 @@ function createFallbackProvider(
       }),
       polling: false,
       stallTimeout: FALLBACK_PROVIDER_TIMEOUT,
+      priority: 2,
       weight: 1,
     });
   }