chrome.alarms
- Description
Use the
chrome.alarmsAPI to schedule code to run periodically or at a specified time in the future. - Permissions
alarms
Summary
- Types
- Methods
- Events
Types
Alarm
Properties
- name
string
Name of this alarm.
- periodInMinutes
number optional
If not null, the alarm is a repeating alarm and will fire again in
periodInMinutesminutes. - scheduledTime
number
Time at which this alarm was scheduled to fire, in milliseconds past the epoch (e.g.
Date.now() + n). For performance reasons, the alarm may have been delayed an arbitrary amount beyond this.
AlarmCreateInfo
Properties
- delayInMinutes
number optional
Length of time in minutes after which the
onAlarmevent should fire. - periodInMinutes
number optional
If set, the onAlarm event should fire every
periodInMinutesminutes after the initial event specified bywhenordelayInMinutes. If not set, the alarm will only fire once. - when
number optional
Time at which the alarm should fire, in milliseconds past the epoch (e.g.
Date.now() + n).
Methods
clear
chrome.alarms.clear(
name?:
string,
callback?:
function,
)
Clears the alarm with the given name.
Parameters
- name
string optional
The name of the alarm to clear. Defaults to the empty string.
- callback
function optional
The
callbackparameter looks like:(wasCleared: boolean) => void- wasCleared
boolean
Returns
Promise<boolean>
Chrome 91+Promises are supported in Manifest V3 and later, but callbacks are provided for backward compatibility. You cannot use both on the same function call. The promise resolves with the same type that is passed to the callback.
clearAll
chrome.alarms.clearAll(
callback?:
function,
)
Clears all alarms.
Parameters
- callback
function optional
The
callbackparameter looks like:(wasCleared: boolean) => void- wasCleared
boolean
Returns
Promise<boolean>
Chrome 91+Promises are supported in Manifest V3 and later, but callbacks are provided for backward compatibility. You cannot use both on the same function call. The promise resolves with the same type that is passed to the callback.
create
chrome.alarms.create(
name?:
string,
alarmInfo:
AlarmCreateInfo,
callback?:
function,
)
Creates an alarm. Near the time(s) specified by alarmInfo, the onAlarm event is fired. If there is another alarm with the same name (or no name if none is specified), it will be cancelled and replaced by this alarm.
In order to reduce the load on the user's machine, Chrome limits alarms to at most once every 1 minute but may delay them an arbitrary amount more. That is, setting delayInMinutes or periodInMinutes to less than 1 will not be honored and will cause a warning. when can be set to less than 1 minute after "now" without warning but won't actually cause the alarm to fire for at least 1 minute.
To help you debug your app or extension, when you've loaded it unpacked, there's no limit to how often the alarm can fire.
Parameters
- name
string optional
Optional name to identify this alarm. Defaults to the empty string.
- alarmInfo
Describes when the alarm should fire. The initial time must be specified by either
whenordelayInMinutes(but not both). IfperiodInMinutesis set, the alarm will repeat everyperiodInMinutesminutes after the initial event. If neitherwhenordelayInMinutesis set for a repeating alarm,periodInMinutesis used as the default fordelayInMinutes. - callback
function optional
Chrome 111+The
callbackparameter looks like:() => void
Returns
Promise<void>
Chrome 111+Promises are supported in Manifest V3 and later, but callbacks are provided for backward compatibility. You cannot use both on the same function call. The promise resolves with the same type that is passed to the callback.
get
chrome.alarms.get(
name?:
string,
callback?:
function,
)
Retrieves details about the specified alarm.
Parameters
Returns
Promise<Alarm | undefined>
Chrome 91+Promises are supported in Manifest V3 and later, but callbacks are provided for backward compatibility. You cannot use both on the same function call. The promise resolves with the same type that is passed to the callback.
getAll
chrome.alarms.getAll(
callback?:
function,
)
Gets an array of all the alarms.
Parameters
Returns
Promise<Alarm[]>
Chrome 91+Promises are supported in Manifest V3 and later, but callbacks are provided for backward compatibility. You cannot use both on the same function call. The promise resolves with the same type that is passed to the callback.