66 lines
1.4 KiB
Go
66 lines
1.4 KiB
Go
|
// For more tutorials: https://blog.learngoprogramming.com
|
||
|
|
//
|
||
|
|
// Copyright © 2018 Inanc Gumus
|
||
|
|
// Learn Go Programming Course
|
||
|
|
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
|
||
|
|
//
|
||
|
|
|
||
|
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
)
|
||
|
|
|
||
|
|
// result stores details about a log line
|
||
|
|
type result struct {
|
||
|
|
domain string
|
||
|
|
visits int
|
||
|
|
// add more metrics when needed
|
||
|
|
}
|
||
|
|
|
||
|
|
// parser keep tracks of the parsing
|
||
|
|
type parser struct {
|
||
|
|
sum map[string]result // metrics per domain
|
||
|
|
domains []string // unique domain names
|
||
|
|
total int // total visits for all domains
|
||
|
|
lines int // number of parsed lines (for the error messages)
|
||
|
|
lerr error // the last error occurred
|
||
|
|
}
|
||
|
|
|
||
|
|
// newParser creates and returns a new parser
|
||
|
|
func newParser() *parser {
|
||
|
|
return &parser{sum: make(map[string]result)}
|
||
|
|
}
|
||
|
|
|
||
|
|
// update the parsing results
|
||
|
|
func parse(p *parser, line string) (r result) {
|
||
|
|
if p.lerr != nil {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
p.lines++
|
||
|
|
|
||
|
|
fields := strings.Fields(line)
|
||
|
|
if len(fields) != 2 {
|
||
|
|
p.lerr = fmt.Errorf("wrong input: %v (line #%d)", fields, p.lines)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
var err error
|
||
|
|
|
||
|
|
r.domain = fields[0]
|
||
|
|
r.visits, err = strconv.Atoi(fields[1])
|
||
|
|
|
||
|
|
if r.visits < 0 || err != nil {
|
||
|
|
p.lerr = fmt.Errorf("wrong input: %q (line #%d)", fields[1], p.lines)
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
// err returns the last error encountered
|
||
|
|
func err(p *parser) error {
|
||
|
|
return p.lerr
|
||
|
|
}
|