github.com/netdata/go.d.plugin@v0.58.1/modules/redis/collect.go (about)

     1  // SPDX-License-Identifier: GPL-3.0-or-later
     2  
     3  package redis
     4  
     5  import (
     6  	"bufio"
     7  	"context"
     8  	"errors"
     9  	"fmt"
    10  	"github.com/blang/semver/v4"
    11  	"regexp"
    12  	"strings"
    13  )
    14  
    15  const precision = 1000 // float values multiplier and dimensions divisor
    16  
    17  func (r *Redis) collect() (map[string]int64, error) {
    18  	info, err := r.rdb.Info(context.Background(), "all").Result()
    19  	if err != nil {
    20  		return nil, err
    21  	}
    22  
    23  	if r.server == "" {
    24  		s, v, err := extractServerVersion(info)
    25  		if err != nil {
    26  			return nil, fmt.Errorf("can not extract server app and version: %v", err)
    27  		}
    28  		r.server, r.version = s, v
    29  		r.Debugf(`server="%s",version="%s"`, s, v)
    30  	}
    31  
    32  	if r.server != "redis" {
    33  		return nil, fmt.Errorf("unsupported server app, want=redis, got=%s", r.server)
    34  	}
    35  
    36  	mx := make(map[string]int64)
    37  	r.collectInfo(mx, info)
    38  	r.collectPingLatency(mx)
    39  
    40  	return mx, nil
    41  }
    42  
    43  // redis_version:6.0.9
    44  var reVersion = regexp.MustCompile(`([a-z]+)_version:(\d+\.\d+\.\d+)`)
    45  
    46  func extractServerVersion(info string) (string, *semver.Version, error) {
    47  	var versionLine string
    48  	for sc := bufio.NewScanner(strings.NewReader(info)); sc.Scan(); {
    49  		line := sc.Text()
    50  		if strings.Contains(line, "_version") {
    51  			versionLine = strings.TrimSpace(line)
    52  			break
    53  		}
    54  	}
    55  	if versionLine == "" {
    56  		return "", nil, errors.New("no version property")
    57  	}
    58  
    59  	match := reVersion.FindStringSubmatch(versionLine)
    60  	if match == nil {
    61  		return "", nil, fmt.Errorf("can not parse version property '%s'", versionLine)
    62  	}
    63  
    64  	server, version := match[1], match[2]
    65  	ver, err := semver.New(version)
    66  	if err != nil {
    67  		return "", nil, err
    68  	}
    69  
    70  	return server, ver, nil
    71  }