elastic-transcoder-lambda.js

'use strict'

console.log('Loading function')

const aws = require('aws-sdk')
const s3 = new aws.S3({ apiVersion: '2006-03-01' })
const elastictranscoder = new aws.ElasticTranscoder()

const config = {
    pipeline_id: process.env.ELASTIC_TRANSCODER_PIPELINE_ID,
    output_folder: process.env.S3_OUTPUT_FOLDER,
    output_key_prefix: process.env.ELASTIC_TRANSCODER_OUTPUT_KEY_PREFIX,
    output_preset_id: process.env.ELASTIC_TRANSCODER_OUTPUT_PRESET_ID
}

const submitTranscodingJob = (key) => {
    console.log(`submitting transcoding job for key ${key}`)
    var params = {
        PipelineId: config.pipeline_id,
        OutputKeyPrefix: config.output_folder,
        Input: {
            Key: key
        },
        Outputs: [{
            Key: `${config.output_key_prefix}-${key}`,
            PresetId: config.output_preset_id,
            ThumbnailPattern: `thumbnails/${key}-{resolution}-{count}`,
        }]
    }

    elastictranscoder.createJob(params, function(err, data) {
        if (err){
            console.log(`An error occurred creating the elastic transcoder job: ${err}`, err.stack); // an error occurred
            return
        }
        
        console.log(`elastic transcoder job successfully submitted:\n${JSON.stringify(data, null, 2)}`)
    })
}

exports.handler = (event, context, callback) => {
    console.log('Received event:', JSON.stringify(event, null, 2))

    const key = decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, ' '))
    
    if(key.includes("/") || key.toLowerCase().endsWith(".mp4") !== true){
        console.log(`skipping ${key} as it either contained "/" or did not end in ".mp4"`)
        return
    }
    
    submitTranscodingJob(key)
}