Format SQL statements in Postgres logs

pg-format-sql.js

// pg-format-sql.js
//
// Format SQL statements in Postgres logs
// i.e. If a log line contains a SQL statement, it will be transformed from this:
//
// 2021-09-14 08:02:37.255 IST [20200] LOG:  statement: SELECT MAX("my_notification"."id") AS "latest_id", COUNT(*) AS "count" FROM "my_notification" WHERE ("my_notification"."is_unread" AND "my_notification"."organization_id" = 1 AND "my_notification"."recipient_id" = 2)
//
// to this:
//
// 2021-09-14 08:02:37.255 IST [20200] LOG:  statement:
//     SELECT
//       MAX("my_notification"."id") AS "latest_id",
//       COUNT(*) AS "count"
//     FROM
//       "my_notification"
//     WHERE
//       (
//         "my_notification"."is_unread"
//         AND "my_notification"."organization_id" = 1
//         AND "my_notification"."recipient_id" = 2
//       )
//
// To use this, you will need node/npm.
//
// Make sure to run `npm install sql-formatter` before you run this script
//
// Usage:
//
//   cat /path/to/postgres/log | node pg-format-sql.js
//   tail -f /path/to/postgres/log | node pg-format-sql.js

const readline = require('readline');
const format = require('sql-formatter').format;

const rl = readline.createInterface({
  input: process.stdin
});

rl.on('line', line => {
  let matches = line.match(/(^.*(?:statement|STATEMENT): *)(.*)/);
  if (matches && matches.length > 0) {
    console.log(matches[1]);
    if (matches[2]) {
      let indent = ' '.repeat(4);
      let formatted = format(matches[2]);
      console.log(formatted.split('\n').map(line => indent + line).join('\n'))
    }
  } else {
    console.log(line);
  }
});