kubenetworks/kubevpn

package dns

import (
    "bytes"
    "text/template"
)

type CoreFile struct {
    Content []byte
}

// Body Gets the Caddyfile contents
func (c *CoreFile) Body() []byte {
    return c.Content
}

// Path Gets the path to the origin file
func (c *CoreFile) Path() string {
    return "CoreFile"
}

// ServerType The type of server this input is intended for
func (c *CoreFile) ServerType() string {
    return "dns"
}

type CoreFileTmpl struct {
    UpstreamDNS string
    Nameservers string
}

func BuildCoreFile(corefileTmpl CoreFileTmpl) (*CoreFile, error) {
    tplText := `
.:53 {
    bind 127.0.0.1
    forward cluster.local {{ .UpstreamDNS }}
    forward . {{ .Nameservers }} {{ .UpstreamDNS }} {
    policy sequential
    max_concurrent 1
    }
    cache 30
    log
    errors
    reload
}`

    tpl, err := template.New("corefile").Parse(tplText)
    if err != nil {
        return nil, err
    }

    data := bytes.NewBuffer(nil)
    if err := tpl.Execute(data, corefileTmpl); err != nil {
        return nil, err
    }

    return &CoreFile{
        Content: data.Bytes(),
    }, nil
}