Lesson 1: Bootstrap a Headless App Builder App

In order to create your barcode application, use the following command:

aio app init my-barcode-app --no-extensions

We select the org, project and workspace for our app, and then be presented with a few options what you want your app to include, for example Serverless Actions, Web UI, CI/CD pipeline, and I/O Events. Since we are building a headless app, we're only interested in using Actions: Deploy Runtime actions.

The second question the CLI asks is which experience cloud or experience platform apps you want to extend or build. In this case, we're going to choose Generic.

To the third question, we'll specify the action name barcode.

From the command line, we are creating a Developer project with everything it needs, from the serverless actions, configuration files, tests, etc.

We didn't include the UI setup, CI/CD pipeline, nor I/O Events. These topics will be covered in other Code Labs.

For our barcode app, we'll start by modifying the following files:

app.config.yaml, which contains all defined actions with their default parameters:

application:
  actions: actions
  web: web-src
  runtimeManifest:
    packages:
      my-app:
        license: Apache-2.0
        actions:
          generic:
            function: actions/generic/index.js
            web: 'yes'
            runtime: 'nodejs:14'
            inputs:
              LOG_LEVEL: debug
            annotations:
              require-adobe-auth: true
              final: true

package.json, which holds your app name, version and all dependencies that will be bundled when deploying the barcode action:

{
  "name": "my-barcode-app",
  "version": "0.0.1",
  "dependencies": {
    "@adobe/aio-sdk": "^2.1.0",
    "node-fetch": "^2.6.0"
  },
  "devDependencies": {
    "jest": "^24.9.0",
    "@adobe/wskdebug": "^1.1.0"
  },
  "scripts": {
    "test": "jest",
    "e2e": "jest --collectCoverage=false --testRegex ./e2e"
  }
}

.env should not be committed, since this is where you'll store your Adobe I/O Runtime secrets (namespace and auth):

# Specify your secrets here
# This file should not be committed to source control

## please provide your Adobe I/O Runtime credentials
# AIO_RUNTIME_AUTH=
# AIO_RUNTIME_NAMESPACE=

actions/barcode/index.js is the source code of your barcode action:

/*
* <license header>
*/

/**
 * This is a sample action showcasing how to access an external API
 */

const { Core } = require('@adobe/aio-sdk')
const fetch = require('node-fetch')
const { errorResponse, getBearerToken, stringParameters, checkMissingRequestInputs } = require('../utils')

// main function that will be executed by Adobe I/O Runtime
async function main (params) {
  // create a Logger
  const logger = Core.Logger('main', { level: params.LOG_LEVEL || 'info' })

  try {
    // 'info' is the default level if not set
    logger.info('Calling the main action')

    // log parameters, only if params.LOG_LEVEL === 'debug'
    logger.debug(stringParameters(params))

    // check for missing request input parameters and headers
    const requiredParams = [/* add required params */]
    const errorMessage = checkMissingRequestInputs(params, requiredParams, ['Authorization'])
    if (errorMessage) {
      // return and log client errors
      return errorResponse(400, errorMessage, logger)
    }

    // extract the user Bearer token from the input request parameters
    const token = getBearerToken(params)

    // replace this with the api you want to access
    const apiEndpoint = 'https://adobeioruntime.net/api/v1/api-docs'

    // fetch content from external api endpoint
    const res = await fetch(apiEndpoint)
    if (!res.ok) {
      throw new Error('request to ' + apiEndpoint + ' failed with status code ' + res.status)
    }
    const content = await res.json()
    logger.debug('fetch content = ' + JSON.stringify(content, null, 2))
    const response = {
      statusCode: 200,
      body: content
    }

    // log the response status code
    logger.info(`${response.statusCode}: successful request`)
    return response
  } catch (error) {
    // log any server errors
    logger.error(error)
    // return with 500
    return errorResponse(500, 'server error', logger)
  }
}

exports.main = main