refactor(client): move compatibility check to custom reviver

Also, update sample nestjs app to include custom JSON.stringify replacer

Author: alonsovb

apps/nest-server/src/app/app.service.ts

@@ -48,7 +48,14 @@ export class AppService {
       const results = await client.query(
         `select returnflag, linestatus, sum(quantity) as sum_qty, sum(extendedprice) as sum_base_price, sum(extendedprice * (1 - discount)) as sum_disc_price, sum(extendedprice * (1 - discount) * (1 + tax)) as sum_charge, avg(quantity) as avg_qty, avg(extendedprice) as avg_price, avg(discount) as avg_disc, count(*) as count_order from lineitem where shipdate <= date '1998-12-01' group by returnflag, linestatus order by returnflag, linestatus`,
       )
-      return { columns: results.columns, rows: results.data }
+      return {
+        columns: results.columns,
+        rows: JSON.stringify(results.data, (key, value) => {
+          if (typeof value !== 'bigint') return value
+
+          return value.toString()
+        }),
+      }
     } catch (error) {
       return (error as PrestoError).message
     }

presto-client/src/client.ts

@@ -8,7 +8,7 @@ import {
   QueryInfo,
   Table,
 } from './types'
-import { parseWithBigInts, isJsonParseContextAvailable } from './utils'
+import { parseWithBigInts } from './utils'
 
 export class PrestoClient {
   private baseUrl: string
@@ -338,13 +338,9 @@ export class PrestoClient {
 
   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)
-    }
+    // 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)
   }
 }
 

presto-client/src/utils.ts

@@ -1,11 +1,20 @@
 /**
  * Parses a JSON including bigger numbers into BigInts
+ * This function checks if JSON.parse reviver callback has a context parameter
+ * and falls back onto the default parsing if not.
+ * 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
  * @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 }) {
+export function parseWithBigInts(_: string, value: unknown, context: { source: string }) {
+  if (!context) return value // Context is not available, fallback to default parse
+  const { source } = context
+  if (!source) return value // Source is not available, fallback to default parse
+
   // Ignore non-numbers
   if (typeof value !== 'number') return value
 
@@ -18,22 +27,3 @@ export function parseWithBigInts(_: string, value: unknown, { source }: { source
 
   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
-}