wait-for-s3-object

Simple tool to let you:

• Wait for a specific S3 object to exist.

• Run a callback once the object exists.

• Check if an S3 object exists.

waitForObjectToExist(filekey, bucketname, waitingCallback, finishedCallback, delayMs=2000)
checkIfObjectExists(fileKey,bucketName,callback)

Works by polling the s3api command via the aws cli.

Installation

First install and configure the AWS cli

Then install with npm

npm i wait-for-s3-object

Usage - wait for S3 object to exist

var tool = require('wait-for-s3-object');

var fileKey = 'folderName/myFile.txt';
var bucket = 'my-awesome-s3-bucket';

tool.waitForObjectToExist(fileKey, bucket, function(err,res){
    console.log('waiting...');
}, function(err,res){
    console.log('object exists!');
})

Usage - check if S3 object exists

tool.checkIfObjectExists(fileKey,bucket, function(err,res){
    if(res){
        console.log("object exists", res);
        //res is an object like this:
        //{
        //  AcceptRanges: 'bytes',
        //  LastModified: '2021-03-18T22:02:51+00:00',
        //  ContentLength: 1224,
        //  ETag: '"..."',
        //  ContentType: 'text/plain',
        //  Metadata: {}
        //}
    }else{
        //object does not exist, or cannot be accessed
        console.log("object does not exist", err); //err is a usually a 404 error
    }
})