Categraf 采集器开发

cd /opt/src

wget https://github.com/flashcatcloud/categraf.git

cd categraf

cd /opt/src 

wget https://studygolang.com/dl/golang/go1.22.5.linux-amd64.tar.gz

tar -zxvf go1.22.5.linux-amd64.tar.gz -C /usr/local/

cat > /etc/profile.d/go.sh <<EOF

export GOROOT=/usr/local/go

export GOPATH=/opt/gopath

export GOBIN=\$GOROOT/bin

export PATH=\$PATH:\$GOBIN

export GO111MODULE=on

export GOPROXY=https://goproxy.cn,direct
EOF

source /etc/profile

go env

cd /opt/src/categraf
make

./categraf -debug

mkdir -p conf/linux-exec

touch conf/linux-exec/linux-exec.toml

# # collect interval
interval = 15

# 获取 linux 内核版本
[[instances]]
labels = { query_type="system" }
field="hostname"
query_command="hostname"

touch inputs/linux-exec/linux-exec.go

package linux-exec


import (
  "log"
  "os/exec"

  "flashcat.cloud/categraf/config"
  "flashcat.cloud/categraf/inputs"
  "flashcat.cloud/categraf/types"
)

//  插件名称，与配置文件中的 input. 开头一致
const inputName = "linux-exec"

// 定义结构体，用于解析配置文件
type LinuxExec struct {
  config.PluginConfig
  Instances []*Instance `toml:"instances"`
}

func init() {
  inputs.Add(inputName, func() inputs.Input {
    return &LinuxExec{}
  })
}

func (pt *LinuxExec) Clone() inputs.Input {
  return &LinuxExec{}
}

func (pt *LinuxExec) Name() string {
  return inputName
}

func (pt *LinuxExec) GetInstances() []inputs.Instance {
  ret := make([]inputs.Instance, len(pt.Instances))
  for i := 0; i < len(pt.Instances); i++ {
    ret[i] = pt.Instances[i]
  }
  return ret
}

type Instance struct {
  config.InstanceConfig

  Field        string `toml:"field"`
  QueryCommand string `toml:"query_command"`
}

// 逻辑处理
func (ins *Instance) Gather(slist *types.SampleList) {
  if ins.Field == "" {
    log.Println("E!", "missing field for linux_exec_query")
    return
  }
  if ins.QueryCommand == "" {
    log.Println("E!", "missing query_command for linux_exec")
    return
  }
  result, err := exec.Command("sh", "-c", ins.QueryCommand).Output()
  if err != nil {
    log.Println("E!", "failed to run query_command for linux_exec:", err)
    return
  }
  // 生成 metrics 查询名称，即 inputName+ins.Field, 如 linux_exec_hostname
  fields := map[string]interface{}{
    ins.Field: 1,
  }
  // 制作 tags
  tags := map[string]string{
    "name":    ins.Field,
    "linux_exec": string(result),
  }
  // 将数据推入 slist
  slist.PushSamples(inputName, fields, tags)
}

vim agent/metrics_agent.go

import (
  // ...
  _ "flashcat.cloud/categraf/inputs/linux-exec"
  // ...
)

# 会生成一个 categraf 二进制文件 
make

# 测试 
-> # ./categraf -debug -test -inputs linux-exec                          
2024/07/25 10:49:59 I! tracing disabled
2024/07/25 10:49:59 main.go:128: I! runner.binarydir: /opt/src/categraf
2024/07/25 10:49:59 main.go:129: I! runner.hostname: sgfoot
2024/07/25 10:49:59 main.go:130: I! runner.fd_limits: (soft=4096, hard=4096)
2024/07/25 10:49:59 main.go:131: I! runner.vm_limits: (soft=unlimited, hard=unlimited)
2024/07/25 10:49:59 provider_manager.go:61: I! use input provider: [local]
2024/07/25 10:49:59 traces_agent.go:19: I! traces agent disabled!
2024/07/25 10:49:59 prometheus_agent.go:19: I! prometheus scraping disabled!
2024/07/25 10:49:59 ibex_agent.go:19: I! ibex agent disabled!
2024/07/25 10:49:59 agent.go:39: I! agent starting
2024/07/25 10:49:59 metrics_agent.go:272: I! input: local.linux-exec started
2024/07/25 10:49:59 agent.go:47: I! [*agent.MetricsAgent] started
2024/07/25 10:49:59 agent.go:50: I! agent started
2024/07/25 10:49:59 metrics_reader.go:54: D! local.linux-exec : before gather once
10:49:59 linux_exec_hostname agent_hostname=sgfoot name=hostname query_type=system linux_exec=sgfoot
 1

# 打包 categraf
tar -zcvf categraf-0.1.0-dev.tar.gz categraf conf

cd /opt/src
wget https://github.com/prometheus/prometheus/releases/download/v2.45.6/prometheus-2.45.6.linux-amd64.tar.gz

tar -zxvf prometheus-2.53.1.linux-amd64.tar.gz -C /opt

mv /opt/prometheus-2.53.1.linux-amd64 /opt/prometheus

cd /opt/prometheus && ls -l

drwxr-xr-x.  2 1001 docker   38 Jul 10 18:31 console_libraries
drwxr-xr-x.  2 1001 docker  173 Jul 10 18:31 consoles
drwxr-xr-x. 14 root root   4.0K Jul 25 11:18 data
-rw-r--r--.  1 1001 docker  12K Jul 10 18:31 LICENSE
-rw-r--r--.  1 1001 docker 3.7K Jul 10 18:31 NOTICE
-rwxr-xr-x.  1 1001 docker 132M Jul 10 18:18 prometheus
-rw-r--r--.  1 1001 docker  934 Jul 10 18:31 prometheus.yml
-rwxr-xr-x.  1 1001 docker 124M Jul 10 18:18 promtool

cat > /etc/systemd/system/prometheus.service < EOF
[Unit]
Description="prometheus"
Documentation=https://prometheus.io/
After=network.target

[Service]
Type=simple

ExecStart=/opt/prometheus/prometheus  --config.file=/opt/prometheus/prometheus.yml --storage.tsdb.path=/opt/prometheus/data --web.enable-lifecycle --enable-feature=remote-write-receiver --query.lookback-delta=2m 

Restart=on-failure
SuccessExitStatus=0
LimitNOFILE=65536
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=prometheus


[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl start prometheus
systemctl enable prometheus

tar -zxvf categraf-0.1.0-dev.tar.gz
vim conf/config.toml

[[writers]]
# url = "http://127.0.0.1:17000/prometheus/v1/write"
url = "http://127.0.0.1:9090/api/v1/write" # 这是 prometheus 的 write API 地址

linux_exec_hostname
linux_exec_hostname{agent_hostname="192.168.1.100", name="hostname", query_type="system", linux_exec="sgfoot"}