# Cron Validator
[](https://travis-ci.org/vcoder4c/cron-validator)
[](https://coveralls.io/github/vcoder4c/cron-validator?branch=master)
### **Features**
- Validate unix cron expression
- Match unit cron expression with specific datetime
- Generate match datetime between two datetime
- Schedule tasks
### **Install**
```shell script
pip install cron-validator
```
### **Run Tests**
**1. Install test requirements**
```shell script
pip install -r requirements/test.txt
```
**2. Run tests (with coverage if wished)**
```shell script
pytest --cov=. test/
```
### Sample
**1. Validate unix cron expression**
```python
from cron_validator import CronValidator
assert CronValidator.parse('* * * * *') is not None # valid
assert CronValidator.parse('*/3 * * * *') is not None # valid
assert CronValidator.parse('*/61 * * * *') is None # invalid
```
**2. Match unit cron expression with specific datetime**
```python
from cron_validator import CronValidator
from cron_validator.util import str_to_datetime
dt_str = '2019-04-23 1:00'
dt = str_to_datetime(dt_str)
assert CronValidator.match_datetime("* * * * *", dt)
assert CronValidator.match_datetime("* * * 4 *", dt)
assert CronValidator.match_datetime("* * * 5 *", dt) is False
assert CronValidator.match_datetime("* * * 1-5 *", dt)
assert CronValidator.match_datetime("* * * 1-3 *", dt) is False
assert CronValidator.match_datetime("* * * 1/5 *", dt) is False
assert CronValidator.match_datetime("* * * * *", dt)
assert CronValidator.match_datetime("0 * * * *", dt)
assert CronValidator.match_datetime("0-30 * * * *", dt)
assert CronValidator.match_datetime("0/30 * * * *", dt)
```
**3. Generate match datetime between two datetime**
```python
from cron_validator import CronValidator
from cron_validator.util import str_to_datetime
from_str = '2019-04-22 00:00'
to_str = '2019-04-23 23:59'
for dt in CronValidator.get_execution_time("0 0 * * *",
from_dt=str_to_datetime(from_str), to_dt=str_to_datetime(to_str)):
print(dt)
# Output:
# 2019-04-22 00:00:00+00:00
# 2019-04-23 00:00:00+00:00
```
**4. Use scheduler for repetitive task**
```python
from cron_validator import CronScheduler
cron_string = "*/1 * * * *"
scheduler = CronScheduler(cron_string)
while True:
if scheduler.time_for_execution():
# Get's called every full minute (excluding first iteration)
print("Now is the next scheduled time.")
```
**5. Use extended cron rules based on AWS EventBridge rules** (from v1.0.6)
The cron validator supports partially extended rules based on the Amazon EvenBridge rule set. [More info.](https://docs.aws.amazon.com/eventbridge/latest/userguide/eb-create-rule-schedule.html#eb-cron-expressions)
Currently we support:
- 'L' for day of the month and day of the week
- 'W' for day of the week.
```python
from cron_validator import CronValidator
from cron_validator.util import str_to_datetime
from cron_validator.regexes import Version
dt_str = '2023-04-28 1:00'
dt = str_to_datetime(dt_str)
assert CronValidator.match_datetime("* * * * 30W", dt, version=Version.EB)
assert CronValidator.match_datetime("* * * * 5L", dt, version=Version.EB)
dt_str = "2022-02-28 1:00"
dt = str_to_datetime(dt_str)
assert CronValidator.match_datetime("* * L * *", dt, version=Version.EB)
```
### License
This project is licensed under the MIT License - see the [LICENSE.txt](LICENSE.txt) file for details