akme/get-closer

package loaders

import (
    "bufio"
    "fmt"
    "github.com/utahta/go-openuri"
    "io"
    "net/url"
    "strings"
)

//LoadHosts loads hosts from file via fs or http request.
func LoadHosts(path string) ([]string, error) {

    o, err := openuri.Open(path)
    if err != nil {
        fmt.Println(err)
    }
    defer o.Close()

    return linesFromReader(o)
}

func linesFromReader(r io.Reader) ([]string, error) {
    var hostsList []string
    scanner := bufio.NewScanner(r)
    for scanner.Scan() {
        s := scanner.Text()
        // if blank line or comment, skip
        if s == "" || strings.HasPrefix(s, "#") {
            continue
        }
        if strings.Contains(s, "#") {
            sArr := strings.SplitN(s, "#", 2)
            s = strings.TrimSpace(sArr[0])
        }
        if strings.HasPrefix(s, "http://") || strings.HasPrefix(s, "https://") {
            host, err := url.Parse(s)
            if err != nil {
                continue
            }
            hostsList = append(hostsList, host.Hostname())
        } else {
            hostsList = append(hostsList, s)
        }
    }
    if err := scanner.Err(); err != nil {
        return nil, err
    }

    return hostsList, nil
}