Lambda: Schedule Expressions Using Rate or Cron

Rate expression

 

 

rate(Value Unit)

Where:

Value can be a positive integer.

Unit can be minute(s), hour(s), or day(s).

For example:

Example	Cron expression
Invoke Lambda function every 5 minutes	rate(5 minutes)
Invoke Lambda function every hour	rate(1 hour)
Invoke Lambda function every seven days	rate(7 days)

Note the following:

• Rate frequencies of less than one minute are not supported.
• For a singular value the unit must be singular (for example, rate(1 day)), otherwise plural (for example, rate(5 days)).

Cron expression

 

 

cron(Minutes Hours Day-of-month Month Day-of-week Year)

All fields are required and time zone is UTC only. The following table describes these fields.

Field	Values	Wildcards
Minutes	0-59	, - * /
Hours	0-23	, - * /
Day-of-month	1-31	, - * ? / L W
Month	1-12 or JAN-DEC	, - * /
Day-of-week	1-7 or SUN-SAT	, - * ? / L #
Year	1970-2199	, - * /

The following table describes the wildcard characters.

 

/ - specifices increments, i.e. 0/15 in the minutes field directs execution to occur every 15 minutes, i.e. 5/10 means 5, 15, 25, 35, etc.

L - specifies "Last"; i.e. If used in Day-of-month field, specifies last day of the month. If used in Day-of-week field, specifies last day of the week (Saturday).

W - specifies "Weekday"; i.e. When used with a date, such as 5/W, specifies the closest weekday to 5th day of the month. If the 5th falls on a Saturday, execution occurs on Friday. If the 5th falls on a Sunday, execution occurs on Monday.

# - specifies the day of the month; i.e. Specifying 3#2 means the second Tuesday of the month (Tuesday is the third day of the 7-day week).

* - specifies All Values; i.e. If used in the Day-of-month field, it means all days in the month.

? - no specified value; i.e. Used in conjunction with another specified value. For example, if a specific date is specified, but you don't care what day of the week it falls on.

"-" - specifies ranges; i.e. 10-12 would mean 10, 11 and 12

' - specifies additional values; i.e. SUN, MON, TUE means Sunday, Monday and Tuesday

The following table lists common examples of cron expressions.

Example	Cron expression
Invoke a Lambda function at 10:00am (UTC) everyday	cron(0 10 * * ? *)
Invoke a Lambda function 12:15pm (UTC) everyday	cron(15 12 * * ? *)
Invoke a Lambda function at 06:00pm (UTC) every Mon-Fri	cron(0 18 ? * MON-FRI *)
Invoke a Lambda function at 8:00am (UTC) every first day of the month	cron(0 8 1 * ? *)
Invoke a Lambda function every 10 min Mon-Fri	cron(0/10 * ? * MON-FRI *)
Invoke a Lambda function every 5 minutes Mon-Fri between 8:00am and 5:55pm (UTC)	cron(0/5 8-17 ? * MON-FRI *)
Invoke a Lambda function at 9 a.m. (UTC) the first Monday of each month	cron(0 9 ? * 2#1 *)

Note the following:

• Cron expressions that lead to rates faster than one minute are not supported.
• One of the day-of-month or day-of-week values must be a question mark (?).