Identify Marketing cloud account (user) details - Journey builder custom activity

Question

I am working on custom activity where I need to identify the account (user) details from which the request came to the custom activity REST APIs.

I thought setting "useJwt": true in the config.json will send the account details but it only sends the activity API parameters in the JWT token.

I have used the JWT token received in POST body of the Hub Exchange app to retrieve the account details as explained in the docs: https://developer.salesforce.com/docs/atlas.en-us.noversion.mc-app-development.meta/mc-app-development/explanation-decoded-jwt.htm

But, for custom activity I can't able to find a way to get the account details as I got in Hub Exchange API.

config.json

{
  "workflowApiVersion": "1.1",
  "metaData": {
    "icon": "img/img_1.png",
    "iconSmall": "img/img_2.png",
    "category": "message"
  },
  "type": "REST",
  "lang": {
    "en-US": {
      "name": "Test custom activity",
      "description": "Testing custom activity"
    }
  },
  "arguments": {
    "execute": {
      "inArguments": [
        {
          "firstName": "{{Contact.Attribute.DE_NAME.FirstName}}"
        },
        {
          "lastName": "{{Contact.Attribute.DE_NAME.LastName}}"
        },
        {
          "emailAddress": "{{Contact.Default.Email}}"
        }
      ],
      "outArguments": [],
      "url": "https://xyz.ngrok.io/activities/execute",
      "verb": "POST",
      "body": "",
      "header": "",
      "format": "json",
      "useJwt": true,
      "timeout": 10000
    }
  },
  "configurationArguments": {
    "applicationExtensionKey": "test-activity-custm-wwq",
    "defaults": {
      "activity": "0"
    },
    "save": {
      "url": "https://xyz.ngrok.io/activities/save",
      "useJwt": true
    },
    "publish": {
      "url": "https://xyz.ngrok.io/activities/publish",
      "verb": "POST",
      "body": "",
      "useJwt": true
    },
    "validate": {
      "url": "https://xyz.ngrok.io/activities/validate",
      "verb": "POST",
      "body": "",
      "useJwt": true
    },
    "stop": {
      "url": "https://xyz.ngrok.io/activities/stop",
      "useJwt": true
    }
  },
  "wizardSteps": [
    {
      "label": "Select anything",
      "key": "1"
    },
    {
      "label": "Confirm Settings",
      "key": "2"
    },
    {
      "label": "Save Settings",
      "key": "3",
      "active": false
    }
  ],
  "userInterfaces": {
    "configModal": {
      "height": 250,
      "width": 600,
      "fullscreen": false
    }
  }
}

Please help me to get account details of the account requesting the custom activity API.

Thanks.

Answer 1

I finally got the user details using the Postmonger event requestTokens and requestedTokens which I found in this Stack Exchange answer.

connection.on('requestedTokens', function(tokens) { ... });

Then, using the fuel2token received in the tokens parameter of requestedTokens event, I got the user details using the GetTokenContext REST API.