[faucet] Add custom metrics

packages/faucet/package.json

@@ -20,6 +20,7 @@
     "cli": "ts-node scripts/cli.ts"
   },
   "dependencies": {
+    "@google-cloud/logging": "^5.3.1",
     "debug": "^4.1.1",
     "eth-lib": "^0.2.8",
     "firebase": "^6.2.2",
@@ -40,6 +41,5 @@
     "firebase-tools": "^7.3.0",
     "rimraf": "2.6.3",
     "yargs": "14.0.0"
-
   }
 }

packages/faucet/src/celo-adapter.ts

@@ -5,7 +5,6 @@ import getStableTokenInstance from './contracts/StableToken'
 import { Escrow } from './contracts/types/Escrow'
 import { GoldToken } from './contracts/types/GoldToken'
 import { StableToken } from './contracts/types/StableToken'
-import { injectDebugProvider } from './debug-provider'
 import { getAddress, sendTx } from './tx'
 
 export class CeloAdapter {
@@ -22,7 +21,8 @@ export class CeloAdapter {
     private readonly escrowAddress: string,
     private readonly goldTokenAddress: string
   ) {
-    injectDebugProvider(web3)
+    // Uncomment when in need for debug
+    // injectDebugProvider(web3)
 
     this.privateKey = this.web3.utils.isHexStrict(pk) ? pk : '0x' + pk
     this.defaultAddress = getAddress(this.web3, this.privateKey)
@@ -31,10 +31,6 @@ export class CeloAdapter {
     this.escrow = getEscrowInstance(this.web3, escrowAddress)
   }
 
-  getStableToken() {
-    return
-  }
-
   async transferGold(to: string, amount: string) {
     return sendTx(this.web3, this.goldToken.methods.transfer(to, amount), this.privateKey, {
       to: this.goldTokenAddress,

packages/faucet/src/database-helper.ts

@@ -1,8 +1,10 @@
+/* tslint:disable max-classes-per-file */
 import { database } from 'firebase-admin'
 import { DataSnapshot } from 'firebase-functions/lib/providers/database'
 import Web3 from 'web3'
 import { CeloAdapter } from './celo-adapter'
 import { NetworkConfig } from './config'
+import { ExecutionResult, logExecutionResult } from './metrics'
 import { generateInviteCode, getPhoneHash, isE164Number, wait } from './utils'
 
 export type Address = string
@@ -49,11 +51,26 @@ export async function processRequest(snap: DataSnapshot, pool: AccountPool, conf
     } else if (request.type === RequestType.Invite) {
       requestHandler = buildHandleInvite(request, snap, config)
     } else {
-      throw new Error(`Unkown request type: ${request.type}`)
+      logExecutionResult(snap.key, ExecutionResult.InvalidRequestErr)
+      return ExecutionResult.InvalidRequestErr
+    }
+
+    const actionResult = await pool.doWithAccount(requestHandler)
+    if (actionResult === ActionResult.Ok) {
+      await snap.ref.update({ status: RequestStatus.Done })
+      logExecutionResult(snap.key, ExecutionResult.Ok)
+      return ExecutionResult.Ok
+    } else {
+      await snap.ref.update({ status: RequestStatus.Failed })
+      const result =
+        actionResult === ActionResult.NoFreeAccount
+          ? ExecutionResult.NoFreeAccountErr
+          : ExecutionResult.ActionTimedOutErr
+      logExecutionResult(snap.key, result)
+      return result
     }
-    const success = await pool.doWithAccount(requestHandler)
-    await snap.ref.update({ status: success ? RequestStatus.Done : RequestStatus.Failed })
   } catch (err) {
+    logExecutionResult(snap.key, ExecutionResult.OtherErr)
     console.error(`req(${snap.key}): ERROR proccessRequest`, err)
     await snap.ref.update({ status: RequestStatus.Failed })
     throw err
@@ -174,6 +191,12 @@ export interface PoolOptions {
 }
 
 const SECOND = 1000
+
+enum ActionResult {
+  Ok,
+  NoFreeAccount,
+  ActionTimeout,
+}
 export class AccountPool {
   constructor(
     private db: database.Database,
@@ -201,17 +224,23 @@ export class AccountPool {
     return this.accountsRef.once('value').then((snap) => snap.val())
   }
 
-  async doWithAccount(action: (account: AccountRecord) => Promise<any>) {
+  async doWithAccount(action: (account: AccountRecord) => Promise<any>): Promise<ActionResult> {
     const accountSnap = await this.tryLockAccountWithRetries()
-    if (accountSnap) {
-      try {
-        await withTimeout(this.options.actionTimeoutMS, () => action(accountSnap.val()))
-      } finally {
-        await accountSnap.child('locked').ref.set(false)
-      }
-      return true
-    } else {
-      return false
+    if (!accountSnap) {
+      return ActionResult.NoFreeAccount
+    }
+
+    try {
+      return withTimeout(
+        this.options.actionTimeoutMS,
+        async () => {
+          await action(accountSnap.val())
+          return ActionResult.Ok
+        },
+        () => ActionResult.ActionTimeout
+      )
+    } finally {
+      await accountSnap.child('locked').ref.set(false)
     }
   }
 

packages/faucet/src/metrics.ts

@@ -0,0 +1,52 @@
+import { Logging } from '@google-cloud/logging'
+
+// See https://firebase.google.com/docs/functions/config-env
+const ProjectID = process.env.GCLOUD_PROJECT || 'celo-faucet'
+
+const logging = new Logging({
+  projectId: ProjectID,
+})
+const log = logging.log('faucetMetrics')
+
+const METADATA = {
+  resource: {
+    labels: {
+      function_name: 'faucetMetrics',
+      project_id: ProjectID,
+      region: 'us-central1',
+    },
+    type: 'cloud_function',
+  },
+}
+
+export enum ExecutionResult {
+  Ok = 'Ok',
+  /** Enqued Faucet Request has invalid type */
+  InvalidRequestErr = 'InvalidRequestErr',
+  /** Failed to obtain a free acount to faucet from */
+  NoFreeAccountErr = 'NoFreeAccountErr',
+  /** Faucet Action timed out */
+  ActionTimedOutErr = 'ActionTimedOutErr',
+  OtherErr = 'OtherErr',
+}
+
+/**
+ * Sends an entry but doesn't block
+ * (we don't want to block waiting for a metric to be sent)
+ */
+function noBlockingSendEntry(entryData: Record<string, any>) {
+  const entry = log.entry(METADATA, entryData)
+  log.write(entry).catch((err: any) => {
+    console.error('EventLogger: error sending entry', err)
+  })
+}
+
+export function logExecutionResult(snapKey: string, result: ExecutionResult) {
+  noBlockingSendEntry({
+    event: 'celo/faucet/result',
+    executionResult: result,
+    failed: result !== ExecutionResult.Ok,
+    snapKey,
+    message: `${snapKey}: Faucet result was ${result}`,
+  })
+}