# cronplan

Cron expression parser for Amazon EventBridge.

## Installation

```sh
go get github.com/winebarrel/cronplan
```

## Usage

```go
package main

import (
	"fmt"
	"time"

	"github.com/winebarrel/cronplan"
)

func main() {
	cron, err := cronplan.Parse("0 10 * * ? *")

	if err != nil {
		panic(err)
	}

	fmt.Println(cron.Minute.Exps[0].Number) //=> 0
	fmt.Println(cron.Hour.Exps[0].Number)   //=> 10
	fmt.Println(cron.String())              //=> "0 10 * * ? *"

	fmt.Println(cron.Match(time.Date(2022, 11, 3, 9, 0, 0, 0, time.UTC)))
	//=> false
	fmt.Println(cron.Match(time.Date(2022, 11, 3, 10, 0, 0, 0, time.UTC)))
	//=> true

	fmt.Println(cron.Next(time.Date(2022, 11, 3, 10, 0, 0, 0, time.UTC)))
	//=> 2022-11-03 10:00:00 +0000 UTC
	fmt.Println(cron.Next(time.Date(2022, 11, 3, 11, 0, 0, 0, time.UTC)))
	//=> 2022-11-04 10:00:00 +0000 UTC
	fmt.Println(cron.NextN(time.Date(2022, 11, 3, 10, 0, 0, 0, time.UTC), 3))
	//=> [2022-11-03 10:00:00 +0000 UTC 2022-11-04 10:00:00 +0000 UTC 2022-11-05 10:00:00 +0000 UTC]

	fmt.Println(cron.Between(
		time.Date(2022, 11, 3, 10, 0, 0, 0, time.UTC),
		time.Date(2022, 11, 4, 10, 0, 0, 0, time.UTC),
	))
	//=> [2022-11-03 10:00:00 +0000 UTC 2022-11-04 10:00:00 +0000 UTC]
}
```

# cronplan CLI

CLI to show next triggers.

## Installation

```
brew install winebarrel/cronplan/cronplan
```

## Usage

```
Usage: cronplan [OPTION] CRON_EXPR
  -h int
    	hour to add
  -n int
    	number of next triggers (default 10)
  -version
    	print version and exit
```

```
$ cronplan '*/10 10 ? * MON-FRI *'
Tue, 11 Oct 2022 10:00:00
Tue, 11 Oct 2022 10:10:00
Tue, 11 Oct 2022 10:20:00
Tue, 11 Oct 2022 10:30:00
Tue, 11 Oct 2022 10:40:00
Tue, 11 Oct 2022 10:50:00
Wed, 12 Oct 2022 10:00:00
Wed, 12 Oct 2022 10:10:00
Wed, 12 Oct 2022 10:20:00
Wed, 12 Oct 2022 10:30:00

$ cronplan -h -9 '*/10 10 ? * MON-FRI *'
Tue, 11 Oct 2022 01:00:00
Tue, 11 Oct 2022 01:10:00
Tue, 11 Oct 2022 01:20:00
Tue, 11 Oct 2022 01:30:00
Tue, 11 Oct 2022 01:40:00
Tue, 11 Oct 2022 01:50:00
Wed, 12 Oct 2022 01:00:00
Wed, 12 Oct 2022 01:10:00
Wed, 12 Oct 2022 01:20:00
Wed, 12 Oct 2022 01:30:00
```

# cronmatch CLI

CLI to check if datetime matches cron expression.

## Installation

```
brew install winebarrel/cronplan/cronmatch
```

## Usage

```
Usage: cronmatch [OPTION] CRON_EXPR DATE
  -h int
    	hour to add
  -no-color
    	disable color output
  -version
    	print version and exit
```

```
$ cronmatch -h -9 '0 1 * * ? *' '2022/10/20 10:00'
'0 1 * * ? *' matches '2022/10/20 10:00' (offset: -9h)

$ cronmatch '0 10 * * ? *' 'Oct 10, 2022, 10:10'
'0 10 * * ? *' does not match 'Oct 10, 2022, 10:10'
```

cf. https://github.com/araddon/dateparse

# Related Links

* [Schedule Expressions for Rules - Amazon CloudWatch Events](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html)
* [cronplan.in](http://cronplan.in/)

# cronviz CLI

CLI to visualize cron schedule.

inspired by [cronv](https://github.com/takumakanari/cronv), [aws-cronv](https://www.npmjs.com/package/aws-cronv).

## Installation

```
brew install winebarrel/cronplan/cronviz
```

## Usage

```
Usage: cronviz [OPTION] CRON_EXPR
  -f string
    	from date (default current date)
  -h int
    	hour to add
  -p string
    	period (default "1d")
  -version
    	print version and exit
```

```
$ cat cron.txt
batch1  0 * * * ? *
batch2  30 */2 * * ? *
batch3  15,45 */3 * * ? *

$ cronviz cron.txt > output.html
$ open output.html
```

cf. https://raw.githack.com/winebarrel/cronplan/main/_example/timeline.html

# Related Links

* [Schedule Expressions for Rules - Amazon CloudWatch Events](https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html)
* [cronplan.in](http://cronplan.in/)