index.ts

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.

// This sample shows how to use the built-in Copy codec preset that can take a source video file that is already encoded
// using H264 and AAC audio, and copy it into MP4 tracks that are ready to be streamed by the AMS service.
// In addition, this preset generates a fast proxy MP4 from the source video. 
// This is very helpful for scenarios where you want to make the uploaded MP4 asset available quickly for streaming, but also generate
// a low quality proxy version of the asset for quick preview, video thumbnails, or low bitrate delivery while your application logic
// decides if you need to backfill any more additional layers (540P, 360P, etc) to make the full adaptive bitrate set complete. 
// This strategy is commonly used by services like YouTube to make content appear to be "instantly" available, but slowly fill in the 
// quality levels for a more complete adaptive streaming experience. See the Encoding_BuiltIn_CopyCodec sample for a version that does not
// generate the additional proxy layer. 
// 
// This is useful for scenarios where you have complete control over the source asset, and can encode it in a way that is 
// consistent with streaming (2-6 second GOP length, Constant Bitrate CBR encoding, no or limited B frames).
// This preset should be capable of converting a source 1 hour video into a streaming MP4 format in under 1 minute, as it is not
// doing any encoding - just re-packaging the content into MP4 files. 
//
// NOTE: If the input has any B frames encoded, we occasionally can get the GOP boundaries that are off by 1 tick
//       which can cause some issues with adaptive switching.
//       This preset works up to 4K and 60fps content.   

import { DefaultAzureCredential } from "@azure/identity";
import {
    AzureMediaServices,
    TransformOutput,
    KnownOnErrorType,
    KnownPriority,
    Transform
} from '@azure/arm-mediaservices';
import * as factory from "../../Common/Encoding/transformFactory";
import * as jobHelper from "../../Common/Encoding/encodingJobHelpers";
import { v4 as uuidv4 } from 'uuid';
// Load the .env file if it exists
import * as dotenv from "dotenv";
dotenv.config();

// This is the main Media Services client object
let mediaServicesClient: AzureMediaServices;

// Copy the samples.env file and rename it to .env first, then populate it's values with the values obtained 
// from your Media Services account's API Access page in the Azure portal.
const subscriptionId: string = process.env.AZURE_SUBSCRIPTION_ID as string;
const resourceGroup: string = process.env.AZURE_RESOURCE_GROUP as string;
const accountName: string = process.env.AZURE_MEDIA_SERVICES_ACCOUNT_NAME as string;

// This sample uses the default Azure Credential object, which relies on the environment variable settings.
// If you wish to use User assigned managed identity, see the samples for v2 of @azure/identity
// Managed identity authentication is supported via either the DefaultAzureCredential or the ManagedIdentityCredential classes
// https://docs.microsoft.com/javascript/api/overview/azure/identity-readme?view=azure-node-latest
// See the following examples for how to authenticate in Azure with managed identity
// https://github.com/Azure/azure-sdk-for-js/blob/@azure/identity_2.0.1/sdk/identity/identity/samples/AzureIdentityExamples.md#authenticating-in-azure-with-managed-identity 

// const credential = new ManagedIdentityCredential("<USER_ASSIGNED_MANAGED_IDENTITY_CLIENT_ID>");
const credential = new DefaultAzureCredential();

// ----------- BEGIN SAMPLE SETTINGS -------------------------------

// You can either specify a local input file with the inputFile or an input Url with inputUrl. 
// Just set the other one to null to have it select the right JobInput class type

// const inputFile = "Media\\<<yourfilepath.mp4>>"; // Place your media in the /Media folder at the root of the samples. Code for upload uses relative path to current working directory for Node;
let inputFile: string;

// This is a hosted sample file to use
let inputUrl: string = "https://amssamples.streaming.mediaservices.windows.net/2e91931e-0d29-482b-a42b-9aadc93eb825/AzurePromo.mp4";

// Args
const outputFolder: string = "./Output";
const namePrefix: string = "encode_builtin_copycodec_withproxy";
const transformName = "CopyCodecWithProxy";

// ----------- END SAMPLE SETTINGS -------------------------------


///////////////////////////////////////////
//   Main entry point for sample script  //
///////////////////////////////////////////
export async function main() {



    mediaServicesClient = new AzureMediaServices(credential, subscriptionId);

    // Configure the jobHelper to simplify the sample code
    // We use the /Common/Encoding/encodingJobHelpers.ts file to consolidate the code for job creation and submission
    // This helps to keep the main sample cleaner and avoid so much redundant code in samples
    jobHelper.setMediaServicesClient(mediaServicesClient);
    jobHelper.setAccountName(accountName);
    jobHelper.setResourceGroup(resourceGroup);
    
    // Create a new Standard encoding Transform for H264
    console.log(`Creating Standard Encoding transform named: ${transformName}`);

    // First we create a TransformOutput
    let transformOutput: TransformOutput[] = [{
        preset: factory.createBuiltInStandardEncoderPreset({
            // uses the built in SaaS Copy Codec preset, which copies source audio and video to MP4 tracks. 
            // This also generates a fast proxy.  See notes at top of this file on constraints and use case.
            presetName: "saasProxyCopyCodec"
        }),
        // What should we do with the job if there is an error?
        onError: KnownOnErrorType.StopProcessingJob,
        // What is the relative priority of this job to others? Normal, high or low?
        relativePriority: KnownPriority.Normal
    }
    ];

    console.log("Creating encoding transform...");

    let transform: Transform = {
        name: transformName,
        description: "Built in preset using the Saas Copy Codec preset. This copies the source audio and video to an MP4 file.",
        outputs: transformOutput
    }

    await mediaServicesClient.transforms.createOrUpdate(resourceGroup, accountName, transformName, transform)
        .then((transform) => {
            console.log(`Transform ${transform.name} created (or updated if it existed already).`);
        })
        .catch((reason) => {
            console.log(`There was an error creating the transform. ${reason}`)
        });

    let uniqueness = uuidv4();
    let input = await jobHelper.getJobInputType(inputFile,inputUrl, namePrefix, uniqueness);
    let outputAssetName = `${namePrefix}-output-${uniqueness}`;
    let jobName = `${namePrefix}-job-${uniqueness}`;
    let locatorName = `locator${uniqueness}`;

    console.log("Creating the output Asset (container) to encode the content into...");

    let outputAsset = await mediaServicesClient.assets.createOrUpdate(resourceGroup, accountName, outputAssetName, {});

    console.log(`Submitting the encoding job to the ${transformName} job queue...`);

    // Submit the job, passing in a custom correlation data object for tracking purposes. You can catch this data on the job output or in Event Grid Events. 
    let job = await jobHelper.submitJob(transformName, jobName, input, outputAssetName, { myTenant: "myCustomTenantName", myId: "1234" });

    console.log(`Waiting for encoding Job - ${job.name} - to finish...`);
    job = await jobHelper.waitForJobToFinish(transformName, jobName);

    if (job.state == "Finished") {
        await jobHelper.downloadResults(outputAssetName as string, outputFolder);
        console.log("Downloaded results to local folder. Please review the outputs from the encoding job.")
    }

    // Publish the output asset for streaming via HLS or DASH
    if (outputAsset !== undefined) {
        let locator = await jobHelper.createStreamingLocator(outputAssetName, locatorName);
        if (locator.name !== undefined) {
            let urls = await jobHelper.getStreamingUrls(locator.name);
        } else throw new Error("Locator was not created or Locator.name is undefined");
    }
}

main().catch((err) => {

    console.error("Error running sample:", err.message);
    console.error(`Error code: ${err.code}`);

    if (err.name == 'RestError') {
        // REST API Error message
        console.error("Error request:\n\n", err.request);
    }

});