Client-Side APIs

Reference for ServiceNow client-side APIs available in the browser. These APIs are shared across all Fluent APIs that execute client-side scripts — Client Scripts, UI Policy scripts (scriptTrue/scriptFalse), UI Actions (client-side), Catalog Client Scripts, and Catalog UI Policies.

Client-side scripts run in the browser and do not support JavaScript module imports (import/export). Use string scripts wrapped in the appropriate function signature (e.g., function onCondition() { } for UI Policies, function onLoad() { } for Client Scripts).

g_form (GlideForm)

The g_form object provides methods to interact with the current form — reading and setting field values, controlling visibility and mandatory state, and displaying messages.

Field Values

Method	Description
getValue(field)	Get the current value of a field
setValue(field, value)	Set a field's value
clearValue(field)	Clear a field's value

Field Display

Method	Description
setVisible(field, bool)	Show (true) or hide (false) a field
setDisplay(field, bool)	Show/hide a field (alternative to setVisible)
setReadOnly(field, bool)	Make a field read-only (true) or editable (false)
setMandatory(field, bool)	Make a field required (true) or optional (false)

Choice Fields

Method	Description
addOption(field, value, label)	Add an option to a choice/dropdown field
clearOptions(field)	Remove all options from a choice/dropdown field

Field Messages

Method	Description
showFieldMsg(field, message, type)	Display a message next to a field (type: 'error', 'info', 'warning')
hideFieldMsg(field)	Remove the message next to a field

Form Messages

Method	Description
addInfoMessage(message)	Display an info banner at the top of the form
addErrorMessage(message)	Display an error banner at the top of the form
addWarningMessage(message)	Display a warning banner at the top of the form
clearMessages()	Remove all banner messages from the form

Form State

Method	Description
isNewRecord()	Returns true if the form is for a new (unsaved) record
getUniqueValue()	Get the sys_id of the current record
hasField(field)	Check if a field exists on the form
submit()	Programmatically submit the form
getFormElement()	Get the underlying DOM form element
flash(field, color, count)	Flash a field to draw user attention

References

Method	Description
getReference(field, callback)	Get the referenced GlideRecord for a reference field. Legacy — prefer GlideAjax for complex lookups

g_user (GlideUser)

The g_user object provides information about the currently logged-in user.

Method	Description
hasRole(role)	Check if the user has a specific role
getFullName()	Get the user's full display name
getUserID()	Get the user's sys_id
getName()	Get the user's username

Additional Client APIs

API	Description
g_scratchpad	Object containing data passed from server-side Display Business Rules to the client. Use this to share server-computed values with client scripts without making additional AJAX calls
g_modal	Modal dialog controls (available in workspace context)
g_service_catalog	Service catalog form methods (available only in catalog item / record producer context)

Where client-side scripts appear in Fluent

Fluent API	Script property	Function signature
Client Script (onLoad)	script	function onLoad() { }
Client Script (onChange)	script	function onChange(control, oldValue, newValue, isLoading) { }
Client Script (onSubmit)	script	function onSubmit() { } — return false to cancel
Client Script (onCellEdit)	script	function onCellEdit(sysIDs, table, oldValues, newValue, callback) { }
UI Policy	scriptTrue / scriptFalse	function onCondition() { }
UI Action (client-side)	script + client.onClick	Custom function name
Catalog Client Script	script	Same signatures as Client Script
Catalog UI Policy	scriptTrue / scriptFalse	function onCondition() { }

Constraints

• No module imports — import/export are not available in the browser. Use Now.include() to reference external .js files (see the now-include-guide topic)
• No third-party libraries — only platform-provided APIs (g_form, g_user, GlideAjax, etc.) are available
• Avoid synchronous server calls — use GlideAjax with async callbacks. getXMLWait() freezes the UI and is deprecated in scoped apps
• Guard onChange against initial load — always check if (isLoading) return; at the start of onChange scripts to prevent execution during form load