bash_prometheus_metrics

This Bash library helps you to save metrics to Prometheus format.

The produced output can be used with the node_exporter textfile collector.

Usage guide

The following global variables can be used:

• metrics_prefix (string, optional, default: empty prefix)
  If present, will be prefixed to all metric names ("_" is implicit).
  Example: metrics_prefix="my"
• metrics_array (array, optional, default: empty array)
  The metrics will be appended to this initial array.
  Example: metrics_array=('my_counter{path="root"} 93' 'my_counter{path="home"} 42')

exporter_add_metric input parameters:

• $1: Metric name (string)
  Example: "storage_bytes"
• $2: Metric type ("gauge" or "counter")
  Example: "gauge"
• $3: Metric description (string)
  Example: "Number of numbers of something"
• $4: Metric value (int or float)
  Example: 1.488
• $5: Metric labels (string, optional, default: no labels)
  String pairs with ":" as key/value separator and ";" separator between multiple pairs.
  Example: "label_one_name:label_one_value;label_two_name:label_two_value"
  Important: whitespaces are not allowed in label keys nor values!
• $6: Additional metric value (int or float, optional)
  Identical to $4 but, if present, must be followed by $7.
• $7: Labels for the additional value (string, optional)
  Identical to $5.

Note: $6 and $7 can be repeated several times (each with a unique label set).

Usage example

# import function definitions
source ./exporter_lib.sh

# (optional) define a prefix for all your metrics
export metrics_prefix=node

# add as many metrics as you have
exporter_add_metric \
  apr_entries \
  gauge \
  "ARP entries by device" \
  12.0 "device:eth0" \
  1.0 "device:eth1" \
  3.0 "device:eth2"

# output all the metrics to a textfile
exporter_show_metrics > /var/lib/node_exporter/my_metrics.prom

Notes

Take always into account the best practices about metric and label naming.