Add script to replay a logged rate cache as rate-server queries

ratesCacheToQueries.ts takes the exchange-rate cache blob captured in the
support logs and converts its subscribed pair lists into the v3/rates query
bodies the app would send, mirroring convertToRatesParams. Emits JSON bodies
or ready-to-run curl commands so a rate issue seen in a user's logs can be
reproduced directly against the rates server.

Author: peachbits

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased (develop)
 
+- added: Verbose logging for exchange rate queries: the request body, resolved/rate-less counts, and errors are captured when the Verbose Logging setting is enabled.
+- added: Exchange-rate cache snapshot in the support log output, plus a `rates-cache-to-queries` script to replay it as rate-server queries.
+
 ## 4.50.0 (2026-07-21)
 
 - added: Changelly swap provider

package.json

@@ -48,6 +48,7 @@
     "precommit": "npm run localize && npm run update-eslint-warnings && lint-staged && tsc && npm test",
     "prepare.ios": "(cd ios; pod repo update; pod install)",
     "prepare": "husky install && ./scripts/prepare.sh",
+    "rates-cache-to-queries": "node -r sucrase/register scripts/ratesCacheToQueries.ts",
     "server": "node ./loggingServer.js",
     "start": "react-native start",
     "test": "TZ=America/Los_Angeles jest",

scripts/ratesCacheToQueries.ts

@@ -0,0 +1,182 @@
+// ---------------------------------------------------------------------------
+// ratesCacheToQueries
+//
+// Converts a logged exchange-rate cache blob (the `***Exchange Rate Cache***`
+// section captured in the support logs, or any JSON matching that shape) into
+// the rate-server query bodies the app would POST to `v3/rates`, so a rate
+// problem seen in a user's logs can be replayed directly against the server.
+//
+// This mirrors `convertToRatesParams` in
+// `src/actions/ExchangeRateActions.ts` — keep the two in sync. It only emits
+// queries for the subscribed pairs present in the blob (`cryptoPairs` /
+// `fiatPairs`); wallet-derived and historical pairs the app adds at runtime
+// are not part of the cache and so are not reproduced here.
+//
+// Usage:
+//   node -r sucrase/register scripts/ratesCacheToQueries.ts <blob.json>
+//   pbpaste | node -r sucrase/register scripts/ratesCacheToQueries.ts
+//   node -r sucrase/register scripts/ratesCacheToQueries.ts <blob.json> --curl
+//
+// Input may be the bare cache JSON or a log excerpt containing it — the first
+// complete JSON object in the text is used. `--curl` emits ready-to-run curl
+// commands instead of the JSON bodies.
+// ---------------------------------------------------------------------------
+
+import * as fs from 'fs'
+
+// Mirrors RATES_SERVER_MAX_QUERY_SIZE in ExchangeRateActions.ts:
+const RATES_SERVER_MAX_QUERY_SIZE = 100
+// One of the v3 rate servers (see RATES_SERVERS in src/util/network.ts):
+const RATES_SERVER = 'https://rates3.edge.app'
+
+// Mirrors removeIsoPrefix in src/util/utils.ts:
+const removeIsoPrefix = (currencyCode: string): string =>
+  currencyCode.replace('iso:', '')
+
+interface CryptoAsset {
+  pluginId: string
+  tokenId?: string | null
+}
+interface CryptoFiatPair {
+  asset: CryptoAsset
+  targetFiat: string
+  isoDate?: string
+  expiration: number
+}
+interface FiatFiatPair {
+  fiatCode: string
+  targetFiat: string
+  isoDate?: string
+  expiration: number
+}
+interface RateCacheBlob {
+  cryptoPairs?: CryptoFiatPair[]
+  fiatPairs?: FiatFiatPair[]
+}
+
+interface RatesQuery {
+  targetFiat: string
+  crypto: Array<{ isoDate: string; asset: CryptoAsset; rate?: number }>
+  fiat: Array<{ isoDate: string; fiatCode: string; rate?: number }>
+}
+
+/**
+ * Group the cached pairs by targetFiat and chunk them into query bodies,
+ * exactly as convertToRatesParams does in the app.
+ */
+function cacheToQueries(blob: RateCacheBlob, isoNow: string): RatesQuery[] {
+  const cryptoPairs = blob.cryptoPairs ?? []
+  const fiatPairs = blob.fiatPairs ?? []
+
+  const grouped = new Map<
+    string,
+    { crypto: CryptoFiatPair[]; fiat: FiatFiatPair[] }
+  >()
+  const bucket = (
+    targetFiat: string
+  ): { crypto: CryptoFiatPair[]; fiat: FiatFiatPair[] } => {
+    let entry = grouped.get(targetFiat)
+    if (entry == null) {
+      entry = { crypto: [], fiat: [] }
+      grouped.set(targetFiat, entry)
+    }
+    return entry
+  }
+  for (const pair of cryptoPairs) bucket(pair.targetFiat).crypto.push(pair)
+  for (const pair of fiatPairs) bucket(pair.targetFiat).fiat.push(pair)
+
+  const queries: RatesQuery[] = []
+  for (const [targetFiat, { crypto, fiat }] of grouped.entries()) {
+    const remainingCrypto = [...crypto]
+    const remainingFiat = [...fiat]
+    while (remainingCrypto.length > 0 || remainingFiat.length > 0) {
+      const cryptoChunk = remainingCrypto.splice(0, RATES_SERVER_MAX_QUERY_SIZE)
+      const fiatChunk = remainingFiat.splice(0, RATES_SERVER_MAX_QUERY_SIZE)
+      queries.push({
+        targetFiat: removeIsoPrefix(targetFiat),
+        crypto: cryptoChunk.map(pair => ({
+          isoDate:
+            pair.isoDate == null
+              ? isoNow
+              : new Date(pair.isoDate).toISOString(),
+          asset: pair.asset
+        })),
+        fiat: fiatChunk.map(pair => ({
+          isoDate:
+            pair.isoDate == null
+              ? isoNow
+              : new Date(pair.isoDate).toISOString(),
+          fiatCode: removeIsoPrefix(pair.fiatCode)
+        }))
+      })
+    }
+  }
+  return queries
+}
+
+/**
+ * Pull the first complete JSON object out of arbitrary text, so a pasted log
+ * excerpt (with surrounding lines) works as well as bare JSON.
+ */
+function extractFirstJsonObject(text: string): string {
+  const start = text.indexOf('{')
+  if (start < 0) throw new Error('No JSON object found in input')
+  let depth = 0
+  let inString = false
+  let escaped = false
+  for (let i = start; i < text.length; i++) {
+    const ch = text[i]
+    if (inString) {
+      if (escaped) escaped = false
+      else if (ch === '\\') escaped = true
+      else if (ch === '"') inString = false
+      continue
+    }
+    if (ch === '"') inString = true
+    else if (ch === '{') depth++
+    else if (ch === '}') {
+      depth--
+      if (depth === 0) return text.slice(start, i + 1)
+    }
+  }
+  throw new Error('Unbalanced JSON object in input')
+}
+
+function main(): void {
+  const args = process.argv.slice(2)
+  const emitCurl = args.includes('--curl')
+  const fileArg = args.find(arg => !arg.startsWith('--'))
+
+  const raw =
+    fileArg != null && fileArg !== '-'
+      ? fs.readFileSync(fileArg, 'utf8')
+      : fs.readFileSync(0, 'utf8')
+
+  const blob = JSON.parse(extractFirstJsonObject(raw)) as RateCacheBlob
+  const isoNow = new Date().toISOString()
+  const queries = cacheToQueries(blob, isoNow)
+
+  if (emitCurl) {
+    for (const query of queries) {
+      const body = JSON.stringify(query).replace(/'/g, "'\\''")
+      process.stdout.write(
+        `curl -sS -X POST '${RATES_SERVER}/v3/rates' -H 'Content-Type: application/json' -d '${body}'\n`
+      )
+    }
+  } else {
+    // One query body per line — each line is a valid v3/rates POST body:
+    for (const query of queries) {
+      process.stdout.write(`${JSON.stringify(query)}\n`)
+    }
+  }
+
+  const cryptoCount = blob.cryptoPairs?.length ?? 0
+  const fiatCount = blob.fiatPairs?.length ?? 0
+  process.stderr.write(
+    `\n${queries.length} quer${
+      queries.length === 1 ? 'y' : 'ies'
+    } from ${cryptoCount} crypto + ${fiatCount} fiat cached pairs\n`
+  )
+}
+
+main()