node_exporter/collector/buddyinfo.go
Ben Kochie dfa53f835a
Use Go 1.13 error features
* Use `errors.Is()` for unwrapping errors.
* Use `%w` error verb in internal error formatting.

Signed-off-by: Ben Kochie <superq@gmail.com>
2020-06-16 14:47:03 +02:00

77 lines
2.1 KiB
Go

// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build !nobuddyinfo
// +build !netbsd
package collector
import (
"fmt"
"strconv"
"github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/procfs"
)
const (
buddyInfoSubsystem = "buddyinfo"
)
type buddyinfoCollector struct {
fs procfs.FS
desc *prometheus.Desc
logger log.Logger
}
func init() {
registerCollector("buddyinfo", defaultDisabled, NewBuddyinfoCollector)
}
// NewBuddyinfoCollector returns a new Collector exposing buddyinfo stats.
func NewBuddyinfoCollector(logger log.Logger) (Collector, error) {
desc := prometheus.NewDesc(
prometheus.BuildFQName(namespace, buddyInfoSubsystem, "blocks"),
"Count of free blocks according to size.",
[]string{"node", "zone", "size"}, nil,
)
fs, err := procfs.NewFS(*procPath)
if err != nil {
return nil, fmt.Errorf("failed to open procfs: %w", err)
}
return &buddyinfoCollector{fs, desc, logger}, nil
}
// Update calls (*buddyinfoCollector).getBuddyInfo to get the platform specific
// buddyinfo metrics.
func (c *buddyinfoCollector) Update(ch chan<- prometheus.Metric) error {
buddyInfo, err := c.fs.BuddyInfo()
if err != nil {
return fmt.Errorf("couldn't get buddyinfo: %w", err)
}
level.Debug(c.logger).Log("msg", "Set node_buddy", "buddyInfo", buddyInfo)
for _, entry := range buddyInfo {
for size, value := range entry.Sizes {
ch <- prometheus.MustNewConstMetric(
c.desc,
prometheus.GaugeValue, value,
entry.Node, entry.Zone, strconv.Itoa(size),
)
}
}
return nil
}