Holiday Exporter

A simple python exporter that exports holidays to Prometheus to help with Alerting. This exporter uses the awesome python-holidays library

The Problem

I want to fire some alerts on workdays only, but Prometheus/Alertmanager doesnt support it!

You are not alone

Solution #1

Create a recording rule on Prometheus with all holidays. This can be really complicated with non fixed holidays, like Easter.

Implementation sugestion

Solution #2

Use this exporter and include it in your expression!

Here is a quick how to use this exporter:

Create an alert rule in Prometheus:

- alert: Is_Holiday
  expr: is_holiday > 0
  labels:
    severity: warning

And create an inhibit_rules in Alertmanager:

- source_match:
    alertname: Is_Holiday
  target_match:
    severity: warning
  equal:
  - severity

With this configuration, any alert with a label "severity = warning" will be inhibited by the holiday exporter. You can go beyond and put some work hours as well:

- alert: Is_Work_Hours
  expr:
    is_holiday > 0
    or
    hour() < 8 + (6 - scalar(is_daylight_saving_time))
    or
    hour() > 17 + (6 - scalar(is_daylight_saving_time))
    or
    day_of_week(vector(time() + (3600 * (6 - scalar(is_daylight_saving_time))))) == 0
    or
    day_of_week(vector(time() + (3600 * (6 - scalar(is_daylight_saving_time))))) == 6
  labels:
    severity: warning

In this rule, my timezone is -6h and it will be triggered if is a holiday, or current hour is > 17 and < 8, or day of week is Saturday or Sunday. When this alert fires, it will inhibit any rule with a label "severity = warning".

How to run:

git clone https://github.com/allangood/holiday_exporter.git
cd holiday_exporter
vi includes/holiday_exporter.yaml
docker build -t holiday_exporter .
docker run -d -p 9137:9137 --name holiday holiday_exporter

Or you can specify your own configuration file: Create your YAML file:

main:
 port: 9137

# Countries, states and provinces accordingly to https://pypi.org/project/holidays
holidays:
  - country: "CA"
    province: "ON"
  - country: "US"
    state: "CA"

Run the holiday_exporter container:

docker run -d -p 9137:9137 -v my_config_file.yaml:/etc/holiday_exporter.yaml -e TZ=America/New_York --restart unless-stopped --name holiday_exporter allangood/holiday_exporter

Version 1.1 and later of this exporter supports custom holidays. You just have to add a section like this to your configuration file:

custom_holidays:
  # Dates must be in ISO format: YYYY-MM-DD
  # Use temaplte {YYYY} for year and {MM} for month
  - date: "{YYYY}-01-01"
    description: "Some event that happens every year"
  - date: "{YYYY}-{MM}-01"
    description: "Some event that repeats every month at specific day"
  - date: "2019-12-17"
    description: "Some day this year only"

Then configure Prometheus to scrape your server:

- job_name: holiday_exporter
  scrape_interval: 10s
  scrape_timeout: 5s
  metrics_path: "/"
  static_configs:
  - targets:
    - <your_server_address>:9137

Metrics exposed:

Sample

# HELP is_holiday Boolean value if today is a statutory holiday
# TYPE is_holiday gauge
is_holiday{country="CA",province="ON",state="None"} 0.0
is_holiday{country="US",province="None",state="CA"} 0.0
is_holiday{country="Custom",province="Custom",state="Custom"} 1.0
# HELP is_daylightsavings Boolean value if today is local daylight saving time
# TYPE is_daylightsavings gauge
is_daylight_savings 0.0

Alternatives

This is another solution

Author:

Allan Good