50 lines
1.2 KiB
Go
50 lines
1.2 KiB
Go
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
)
|
||
|
|
|
||
|
|
// domain represents a domain log record
|
||
|
|
type domain struct {
|
||
|
|
name string
|
||
|
|
visits int
|
||
|
|
}
|
||
|
|
|
||
|
|
// parser parses a log file and provides an iterator to iterate upon the domains
|
||
|
|
//
|
||
|
|
// the parser struct is carefully crafted to be usable using its zero values except the map field
|
||
|
|
type parser struct {
|
||
|
|
sum map[string]int // visits per unique domain
|
||
|
|
domains []domain // unique domain names
|
||
|
|
total int // total visits to all domains
|
||
|
|
lines int // number of parsed lines (for the error messages)
|
||
|
|
}
|
||
|
|
|
||
|
|
// newParser creates and returns a new parser.
|
||
|
|
func newParser() parser {
|
||
|
|
return parser{sum: make(map[string]int)}
|
||
|
|
}
|
||
|
|
|
||
|
|
// parse parses the given text and returns a domain struct
|
||
|
|
func parse(p parser, line string) (dom domain, err error) {
|
||
|
|
// var dom domain
|
||
|
|
// var err error
|
||
|
|
|
||
|
|
fields := strings.Fields(line)
|
||
|
|
if len(fields) != 2 {
|
||
|
|
err = fmt.Errorf("wrong input: %v (line #%d)", fields, p.lines)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
name, visits := fields[0], fields[1]
|
||
|
|
|
||
|
|
n, err := strconv.Atoi(visits)
|
||
|
|
if n < 0 || err != nil {
|
||
|
|
err = fmt.Errorf("wrong input: %q (line #%d)", visits, p.lines)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
return domain{name: name, visits: n}, nil
|
||
|
|
}
|