canaryd

canaryd is an aggregator for measurements taken by sensord. It ingests metrics via UDP and stores a small window of them in a Redis instance. Those measurements are then made available via a simple HTTP API and Websocket.

Build

$ go get github.com/canaryio/canaryd
$ cd $GOPATH/src/github.com/canaryio/canaryd
$ godep get
$ godep go build

Configuration

canaryd is configured via the environment. The following values are allowed:

• PORT - port the HTTP and UDP servers should bind to, defaulting to '5000'
• REDIS_URL - URL for the redis backend, defaults to redis://localhost:6379
• REDIS_PUBLISH - set to 1 to publish measurements via Redis; PSUBSCRIBE to measurements:* to get measurements for all check IDs
• RETENTION - how long to store measurements, in seconds; defaults to 60

canaryd allows internal performance metrics to be captured. To send them to Librato, set the following environment variables:

• LIBRATO_EMAIL - email address of your librato account
• LIBRATO_TOKEN - token for your Librato account
• LIBRATO_SOURCE - defaults to the server's hostname

To send them to InfluxDB:

• INFLUXDB_HOST - the InfluxDB hostname
• INFLUXDB_DATABASE - database to store the metrics in
• INFLUXDB_USER, INFLUXDB_PASSWORD - authentication credentials

You can also dump them to stderr:

• LOGSTDERR - set to 1 to enable

Usage Example

# connect to a single local sensor
$ godep go run canaryd.go
2014/05/24 14:00:41 fn=httpServer listening=true port=5000
2014/05/24 14:00:41 fn=udpServer listening=true port=5000

###Websocket Measurements can be received in (near) realtime via websocket. You can create a websocket connection at <host>:<PORT>/ws/checks/{check_id}/measurements. This connection will stream measurements back for the check ID you've specified.