firehol/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package clickhouse

import (
    "strconv"

    "github.com/netdata/netdata/go/plugins/plugin/go.d/pkg/web"
)

const querySystemDisks = `
SELECT
    name,
    sum(free_space) as free_space,
    sum(total_space) as total_space 
FROM
    system.disks 
GROUP BY
    name FORMAT CSVWithNames
`

type diskStats struct {
    name       string
    totalBytes int64
    freeBytes  int64
}

func (c *ClickHouse) collectSystemDisks(mx map[string]int64) error {
    req, _ := web.NewHTTPRequest(c.RequestConfig)
    req.URL.RawQuery = makeURLQuery(querySystemDisks)

    seen := make(map[string]*diskStats)

    getDisk := func(name string) *diskStats {
        s, ok := seen[name]
        if !ok {
            s = &diskStats{name: name}
            seen[name] = s
        }
        return s
    }

    var name string

    err := c.doHTTP(req, func(column, value string, lineEnd bool) {
        switch column {
        case "name":
            name = value
        case "free_space":
            v, _ := strconv.ParseInt(value, 10, 64)
            getDisk(name).freeBytes = v
        case "total_space":
            v, _ := strconv.ParseInt(value, 10, 64)
            getDisk(name).totalBytes = v
        }
    })
    if err != nil {
        return err
    }

    for _, disk := range seen {
        if _, ok := c.seenDisks[disk.name]; !ok {
            v := &seenDisk{disk: disk.name}
            c.seenDisks[disk.name] = v
            c.addDiskCharts(v)
        }

        px := "disk_" + disk.name + "_"

        mx[px+"free_space_bytes"] = disk.freeBytes
        mx[px+"used_space_bytes"] = disk.totalBytes - disk.freeBytes
    }

    for k, v := range c.seenDisks {
        if _, ok := seen[k]; !ok {
            delete(c.seenDisks, k)
            c.removeDiskCharts(v)
        }
    }

    return nil
}