Variables

Forms is currently in Early Access. To learn more about Auth0 release stages, review Product Release Stages.

Variables allow you to access data contained in Forms and Flows to create custom business logic and automations.

Some basic considerations to using variables are:

Variables are surrounded by curly brackets {{ variable }}.
If a variable doesn't exist or can't be resolved, it has the same effect as an undefined variable.
You can use nullish operators to handle null or undefined variables, for example:{{fields.foo ?? fields.bar}}.

Available variables

You can use different types of variables to reference and transform data you gather from customers with Forms and Flows.

Variable	Syntax	Where	Description
Context	`{{context.*}}`	Forms / Flows	Reference context data of the current transaction
Form fields	`{{fields.*}}`	Forms / Flows	Reference data from your form fields and hidden fields
Shared variables	`{{vars.*}}`	Forms / Flows	Reference data stored as shared variables
Flow actions output	`{{actions.*}}`	Flows	Reference data from the output response of previous flow actions
Helper functions	`{{functions.*}}`	Forms / Flows	Helper functions to transform data

Context variables

Forms and flows automatically inherit context variables from the current transaction, this includes information about the user, application and the tenant name.

For example: {{context.user.user_id}} references the user_id of the user object.

Example of context object

{
  "user": {
    "user_id": "auth0|658409...",
    "name": "ana@travel0.com",
    "nickname": "ana",
    "email": "ana@travel0.com",
    "email_verified": true,
    "picture": "https://s.gravatar.com/avatar/8eb1b522f6...",
    "user_metadata": {},
    "app_metadata": {},
    "created_at": "2023-12-21T09:46:40.487Z",
    "updated_at": "2024-05-07T10:44:26.271Z",
    "last_password_reset": "2023-12-21T09:49:08.932Z",
    "identities": [
      {
        "user_id": "6584...",
        "isSocial": false,
        "provider": "auth0",
        "connection": "Username-Password-Authentication"
      }
    ]
  },
  "client": {
    "client_id": "xpeg5...",
    "name": "My App"
  },
  "tenant": {
    "name": "tenant-testing"
  },
  "transaction": {
    "state": "hKFo2SBId2M0..."
  }
}

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Form fields variables

Field variables contain data collected from the user from input fields in the form and data from hidden fields. The data of each field varies depending on the field type. For example: {{fields.first_name}} references the input value of a field with the ID first_name.

Flow output actions variables

When a flow action is executed, it generates an output object response that can be referenced in subsequent actions. For example: {{actions.generate_otp.code}} references the output code of the action with ID generate_otp.

Shared variables

You can store variables to be shared with subsequent flows or even with form components in the same transaction. Shared variables are ephemeral and are associated with a specific form journey. Their values cannot be accessed outside of that journey. For example: {{vars.external_id}} references the value of a shared variable with ID external_id.

Shared variables:

are internal (server-side) and not exposed to the browser (client-side).
can be resolved and exposed to the browser if you referenced a shared variable in the form component.
might have sensitive information, so take care when you access shared variable to avoid any unnecessary or unintentional exposure.

Helper functions

Helper functions let you transform data and perform simple operations. For example: {{functions.toString(fields.privacy_policies)}} transform the value of the field with ID privacy_policies using the toString() function.

The available helper functions are:

Function	Description	Example
toArray(value)	Converts value to an array	{{ functions.toArray('abc') }} // ['abc']
toBoolean(value)	Converts value to a boolean value	{{ functions.toBoolean(1) }} // true {{ functions.toBoolean(0) }} // false
length(value)	Returns the length of the parameter value	{{ functions.length('auth0') }} // 5
mask(value)	Masks a value to avoid be exposed in Executions	{{ functions.mask('my_awesome_secret') }} // ███
toNumber(value)	Converts value to a number	{{ functions.toNumber('123') }} // 123
random(min, max, [boolean])	Returns a random number between the inclusive min and max	{{ functions.random(0, 6) }} // 4 {{ functions.random(0, 6, true) }} // 3.8523497...
slice(value, start, end)	Returns a section of a value array or string between the start and end indexes	{{ functions.slice( 'example', 3, 5) }} // 'mp'
toString(value)	Converts value to a string	{{ functions.toString(123) }} // '123'
substring(value, start, end)	Returns a section of a value between the start and end indexes. Read about the differences of slice and substring functions	{{ functions.substring( 'example’', 3, 5) }} // 'mp'
toTimestamp()	Returns the current UNIX timestamp	{{ functions.toTimestamp() }} // 1628761483
toTimestamp(date)	Returns the provided date in UNIX time	{{ functions.toTimestamp('2021-04-30T10:02:50.876Z') }} // 1619776970

Variables best practices

Use meaningful IDs

When you add a Form field or a Flow action, the ID is automatically generated.

Update the ID to a more descriptive value so you can identify the information it contains. For example, if you create a Form field that stores the user’s first name, update the ID to first_name.

Be mindful when updating existing IDs

If a variable is already in use and you need to modify the ID, identify where you have referenced it and update the ID accordingly to avoid undefined or empty values.

Check Flow executions

If you see an unexpected variable value, use the Executions view to troubleshoot the variable.

The autocomplete menu helps you locate and properly reference existing variables.

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