fix(client): parse Presto JSON response with custom reviver and BigInts

.nvmrc

@@ -1 +1 @@
-18.17.1
+21.0.0

presto-client/src/client.ts

@@ -8,6 +8,7 @@ import {
   QueryInfo,
   Table,
 } from './types'
+import { parseWithBigInts, isJsonParseContextAvailable } from './utils'
 
 export class PrestoClient {
   private baseUrl: string
@@ -270,7 +271,7 @@ export class PrestoClient {
         throw new Error(`Query failed: ${JSON.stringify(await response.text())}`)
       }
 
-      const prestoResponse = (await response.json()) as PrestoResponse
+      const prestoResponse = (await this.prestoConversionToJSON({ response })) as PrestoResponse
       if (!prestoResponse) {
         throw new Error(`Query failed with an empty response from the server.`)
       }
@@ -334,6 +335,17 @@ export class PrestoClient {
       method,
     })
   }
+
+  private async prestoConversionToJSON({ response }: { response: Response }): Promise<unknown> {
+    const text = await response.text()
+    if (isJsonParseContextAvailable()) {
+      // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+      // @ts-ignore JSON.parse with a 3 argument reviver is a stage 3 proposal with some support, allow it here.
+      return JSON.parse(text, parseWithBigInts)
+    } else {
+      return JSON.parse(text)
+    }
+  }
 }
 
 export default PrestoClient

presto-client/src/utils.ts

@@ -0,0 +1,39 @@
+/**
+ * Parses a JSON including bigger numbers into BigInts
+ * @param _ Key
+ * @param value Parsed value
+ * @param context Context with source text
+ * @returns Parsed object with BigInts where required
+ */
+export function parseWithBigInts(_: string, value: unknown, { source }: { source: string }) {
+  // Ignore non-numbers
+  if (typeof value !== 'number') return value
+
+  // If not an integer, use the value
+  // TODO: Check if Presto can return floats that could also lose precision
+  if (!Number.isInteger(value)) return value
+
+  // If number is a safe integer, we can use it
+  if (Number.isSafeInteger(value)) return value
+
+  return BigInt(source)
+}
+
+/**
+ * Checks if JSON.parse reviver callback has a context parameter
+ * See also:
+ * - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse#browser_compatibility
+ * - https://github.com/tc39/proposal-json-parse-with-source
+ *
+ * This implementation is based on suggestion here:
+ * - https://github.com/tc39/proposal-json-parse-with-source/issues/40
+ */
+export function isJsonParseContextAvailable() {
+  let contextAvailable
+  // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+  // @ts-ignore
+  JSON.parse('"x"', function (key, value, x) {
+    contextAvailable = typeof x !== 'undefined'
+  })
+  return contextAvailable
+}