InVisionApp/go-health

package diskchk

import (
    "fmt"

    "github.com/shirou/gopsutil/disk"
)

// DiskUsageConfig is used for configuring the go-diskusage check.
//
// "Path" is _required_; path to check directory/drive (ex. /home/user)
// "WarningThreshold" is _required_; set percent (more than 0 and less 100) of free space at specified path,
//  which triggers warning.
// "CriticalThreshold" is _required_; set percent (more than 0 and less 100) of free space at specified path,
//  which triggers critical.
type DiskUsageConfig struct {
    Path              string
    WarningThreshold  float64
    CriticalThreshold float64
}

// DiskUsage implements the "ICheckable" interface.
type DiskUsage struct {
    Config *DiskUsageConfig
}

func NewDiskUsage(cfg *DiskUsageConfig) (*DiskUsage, error) {
    if cfg == nil {
        return nil, fmt.Errorf("Passed in config cannot be nil")
    }

    if err := validateDiskUsageConfig(cfg); err != nil {
        return nil, fmt.Errorf("Unable to validate diskusage config: %v", err)
    }

    return &DiskUsage{
        Config: cfg,
    }, nil
}

// Status is used for performing a diskusage check against a dependency; it satisfies
// the "ICheckable" interface.
func (d *DiskUsage) Status() (interface{}, error) {
    stats, err := disk.Usage(d.Config.Path)

    if err != nil {
        return nil, fmt.Errorf("Error getting disk usage: %v", err)
    }

    diskUsage := stats.UsedPercent

    if diskUsage >= d.Config.CriticalThreshold {
        return nil, fmt.Errorf("Critical: disk usage too high %.2f percent", diskUsage)
    }

    if diskUsage >= d.Config.WarningThreshold {
        return nil, fmt.Errorf("Warning: disk usage too high %.2f percent", diskUsage)
    }

    return nil, nil
}

func validateDiskUsageConfig(cfg *DiskUsageConfig) error {
    if cfg == nil {
        return fmt.Errorf("Main config cannot be nil")
    }

    if cfg.Path == "" {
        return fmt.Errorf("Path can not be nil")
    }

    if cfg.WarningThreshold > 100.0 || cfg.WarningThreshold < 0 {
        return fmt.Errorf("Invalid warning threshold value (more 100 or less 0)")
    }

    if cfg.CriticalThreshold > 100.0 || cfg.CriticalThreshold < 0 {
        return fmt.Errorf("Invalid critical threshold value (more 100 or less 0)")
    }

    return nil
}