MySQLDump RDS to S3 using Lambda

Question

I am looking up how to export RDS to S3 using Lambda, so far I found a Python node and Java API but I can't find a way of programmatically running something like mysqldump without the actual executable.

Is there a way of doing it?

I am thinking using node.js to call SHOW CREATE TABLE for each element in SHOW TABLES

Then somehow create extended INSERT statements.

Answer 1

Yes it is possible, you need to include mysqldump executable with your lambda package though!

Sample script in Node.js for backup using mysqldump and uploading to S3.

var S3 = require('./S3Uploader'); //custom S3 wrapper with stream upload functionality

var fs = require('fs');
var path = require('path');
var util = require('util');

const writeFile = util.promisify(fs.writeFile);

const execFile = util.promisify(require('child_process').execFile);
const exec = util.promisify(require('child_process').exec);

async function backupToS3(){

    var backupName = 'mysqlbackup-'+new Date().toISOString()+'.gz'

    var content = `cd /tmp
                   BACKUPNAME="[BACKUP_NAME]"
                  [EXE_PATH]/mysqldump --host [DB_ENDPOINT] --port [DB_PORT] -u [DB_USER] --password="[DB_PASS]" [DB_NAME] | gzip -c > $BACKUPNAME
                  `;
    content = content.replace('[BACKUP_NAME]', backupName);
    content = content.replace('[DB_ENDPOINT]', 'xx'); //get from lambda environment variables
    content = content.replace('[DB_PORT]', 'xx'); //get from lambda environment variables
    content = content.replace('[DB_USER]', 'xx'); //get from lambda environment variables
    content = content.replace('[DB_PASS]', 'xx'); //get from lambda environment variables
    content = content.replace('[DB_NAME]', 'xx'); //get from lambda environment variables
    content = content.replace('[EXE_PATH]', __dirname+'/tools'); //path where mysqldump executable is located withing the lambda package

    //generate backup script
    await writeFile('/tmp/db_backup.sh', content);
    fs.chmodSync('/tmp/db_backup.sh', '755');

    //run script
    var res1 = await execFile('/tmp/db_backup.sh');

    //stream upload to S3
    var res2 = await S3.uploadFile('/tmp/'+backupName, 'backups');

    //cleanup local backup (this should cleanup automatically according to lambda lifecycle)
    var res3 = await exec('rm /tmp/'+backupName);

    return  'Backup complete';
};

Sample S3Uploader posted here - Loading File directly from Node js req body to S3