apache--hertzbeat/home/docs/help/time_expression.md

id, title, sidebar_label, keywords

id	title	sidebar_label	keywords
time_expression	Time Expression	Time Expression	dynamic time time expressions

Introduction

HertzBeat supports using expressions to calculate relative time during monitoring collection, allowing for more flexible time definitions in monitoring templates.

Syntax

${FORMATTER [{ + | - }`<DURATION>` `<TIME_UNIT>`]}

• FORMATTER: Determines the format of the expression's result
• DURATION: Size of the time period, a positive integer
• TIME_UNIT: Unit of the time period

Supported Formatting Types

Example outputs are based on the current time being 2022-04-24 02:40:00.123

Name	Description	Example
@now	Formats as yyyy-MM-dd HH:mm:ss	2022-04-24 02:40:00
@date	Formats as yyyy-MM-dd	2022-04-24
@timestamp10	Returns 10-digit timestamp	1650768000
@timestamp	Returns 13-digit timestamp	1650768000000
@time	Formats as HH:mm:ss	02:40:00
@year	Formats as yyyy	2022
@month	Formats as MM	04
@day	Formats as dd	24
@hour	Formats as HH	02
@minute	Formats as mm	40
@millisecond	Formats as SSS	123
@second	Formats as ss	00

Supported Time Units

Name	Description
y	Year
M	Month
d	Day
H	Hour
m	Minute
s	Second
w	Week

Where to Use

• Request parameters for HTTP protocol monitoring types
• Request Body for HTTP protocol monitoring types

Usage Examples

1. Simple expression
   • ${@now} gets the current time and formats it as yyyy-MM-dd HH:mm:ss
   • ${@time+1H} calculates the time one hour from now and formats it as HH:mm:ss
   • ${@time+1H+15m+30s} calculates the time one hour, 15 minutes, and 30 seconds from now and formats it as HH:mm:ss
2. Complex expression template (if the built-in formatter does not meet your needs, you can combine multiple expressions)
   • ${@year}年${@month}月${@day}日 returns the current date formatted as yyyy年MM月dd日