Kiruna

Docker orchestration and watchdog.

What does it do

Kiruna is a service that you run on your docker host (typically inside a docker container) and feed with a kiruna.conf configuration file. It will:

• Start services from this config file
• Monitor their health (and restart them when needed)
• Monitor the config file for changes (so you can just push it with tools like Ansible, Chef etc. and kiruna will act upon it)
• Register IP/port pairs for each of the services with ETCD for use by load balancers etc.

Configuration file

The configuration file is called kiruna.conf and must be accessible in the root of this project or in an environment variable called KIRUNA_CONF.

It is a JSON file with the following structure.

{
"Variables": {
    "key": "value"
},
"Registration": {
    "Host": "host-ip of etcd server",
    "Port": "4001",
    "Ip": "",
    "Ttl": "ttl-of-registrations",
    "Prefix": "prefix-in-etcd-key-space"
},
"Defaults": {
    "any-service-key": "value"
},
"Services": {
    "service-name": {
        "HardDeploy": "if-true-stop-old-container-then-restart",
        "Registry": "custom-registry-host-colon-port",
        "Image": "docker-image-name",
        "Tag": "docker-image-tag",
        "Enabled": "true|false",
        "PublishAllPorts": "true|false",
        "Dependencies": ["other-service-name"],
        "SettleTimeout": "time-needed-by-load-balancers-etc-after-a-start-in-ms",
        "NetworkMode": "any-docker-network-mode",
        "Ports": {
            "container-port": "host-port"
        },
        "Health": {
             "Http": {
                "Port": "docker-port-to-check-on",
                "Ip": "ip-address-to-check-on (for public IP mapping)",
                "Path": "/this-is-my-health-indicator"
            }
        },
        "Environment": {
            "key": "value"
        },
        "Volumes": {
            "container-path": "host-path"
        }
    }
}
}