data-transport-layer: add new metrics (#2391)

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

.changeset/new-jokes-walk.md

+---
+'@eth-optimism/data-transport-layer': patch
+---
+
+Add new metrics to the data-transport-layer

packages/data-transport-layer/src/services/l2-ingestion/service.ts

@@ -6,7 +6,7 @@ import { BigNumber } from 'ethers'
 import { LevelUp } from 'levelup'
 import axios from 'axios'
 import bfj from 'bfj'
-import { Gauge } from 'prom-client'
+import { Gauge, Histogram } from 'prom-client'
 
 /* Imports: Internal */
 import { handleSequencerBlock } from './handlers/transaction'
@@ -16,6 +16,7 @@ import { L1DataTransportServiceOptions } from '../main/service'
 
 interface L2IngestionMetrics {
   highestSyncedL2Block: Gauge<string>
+  fetchBlocksRequestTime: Histogram<string>
 }
 
 const registerMetrics = ({
@@ -27,6 +28,12 @@ const registerMetrics = ({
     help: 'Highest Synced L2 Block Number',
     registers: [registry],
   }),
+  fetchBlocksRequestTime: new client.Histogram({
+    name: 'data_transport_layer_fetch_blocks_time',
+    help: 'Amount of time fetching remote L2 blocks takes',
+    buckets: [0.1, 5, 15, 50, 100, 500],
+    registers: [registry],
+  }),
 })
 
 export interface L2IngestionServiceOptions
@@ -240,6 +247,8 @@ export class L2IngestionService extends BaseService<L2IngestionServiceOptions> {
           )
         }
 
+        const end = this.l2IngestionMetrics.fetchBlocksRequestTime.startTimer()
+
         const resp = await axios.post(
           this.state.l2RpcProvider.connection.url,
           req,
@@ -249,6 +258,8 @@ export class L2IngestionService extends BaseService<L2IngestionServiceOptions> {
           yieldRate: 4096, // this yields abit more often than the default of 16384
         })
 
+        end()
+
         result = respJson.result
         if (result === null) {
           retry++

packages/data-transport-layer/src/services/main/service.ts

@@ -89,6 +89,10 @@ export class L1DataTransportService extends BaseService<L1DataTransportServiceOp
       }
     })
 
+    this.state.metrics.client.collectDefaultMetrics({
+      prefix: 'data_transport_layer_'
+    })
+
     this.state.failureCounter = new this.state.metrics.client.Counter({
       name: 'data_transport_layer_main_service_failures',
       help: 'Counts the number of times that the main service fails',