frostfs-node/pkg/util/locode/db/airports/calls.go
Evgenii Stratonikov 71b87155ef [#521] *: use stdlib errors package
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2021-05-19 16:42:54 +03:00

194 lines
3.7 KiB
Go

package airportsdb
import (
"encoding/csv"
"errors"
"fmt"
"io"
"os"
"strconv"
"github.com/nspcc-dev/neofs-node/pkg/util/locode"
locodedb "github.com/nspcc-dev/neofs-node/pkg/util/locode/db"
)
const (
_ = iota - 1
_ // Airport ID
_ // Name
airportCity
airportCountry
airportIATA
_ // ICAO
airportLatitude
airportLongitude
_ // Altitude
_ // Timezone
_ // DST
_ // Tz database time zone
_ // Type
_ // Source
airportFldNum
)
type record struct {
city,
country,
iata,
lat,
lng string
}
// Get scans records of the OpenFlights Airport to in-memory table (once),
// and returns entry that matches passed UN/LOCODE record.
//
// Records are matched if they have the same country code and either
// same IATA code or same city name (location name in UN/LOCODE).
//
// Returns locodedb.ErrAirportNotFound if no entry matches.
func (db *DB) Get(locodeRecord locode.Record) (*locodedb.AirportRecord, error) {
if err := db.initAirports(); err != nil {
return nil, err
}
records := db.mAirports[locodeRecord.LOCODE.CountryCode()]
for i := range records {
if locodeRecord.LOCODE.LocationCode() != records[i].iata &&
locodeRecord.NameWoDiacritics != records[i].city {
continue
}
lat, err := strconv.ParseFloat(records[i].lat, 64)
if err != nil {
return nil, err
}
lng, err := strconv.ParseFloat(records[i].lng, 64)
if err != nil {
return nil, err
}
return &locodedb.AirportRecord{
CountryName: records[i].country,
Point: locodedb.NewPoint(lat, lng),
}, nil
}
return nil, locodedb.ErrAirportNotFound
}
const (
_ = iota - 1
countryName
countryISOCode
_ // dafif_code
countryFldNum
)
// CountryName scans records of the OpenFlights Country table to in-memory table (once),
// and returns name of the country by code.
//
// Returns locodedb.ErrCountryNotFound if no entry matches.
func (db *DB) CountryName(code *locodedb.CountryCode) (name string, err error) {
if err = db.initCountries(); err != nil {
return
}
argCode := code.String()
for cName, cCode := range db.mCountries {
if cCode == argCode {
name = cName
break
}
}
if name == "" {
err = locodedb.ErrCountryNotFound
}
return
}
func (db *DB) initAirports() (err error) {
db.airportsOnce.Do(func() {
db.mAirports = make(map[string][]record)
if err = db.initCountries(); err != nil {
return
}
err = db.scanWords(db.airports, airportFldNum, func(words []string) error {
countryCode := db.mCountries[words[airportCountry]]
if countryCode != "" {
db.mAirports[countryCode] = append(db.mAirports[countryCode], record{
city: words[airportCity],
country: words[airportCountry],
iata: words[airportIATA],
lat: words[airportLatitude],
lng: words[airportLongitude],
})
}
return nil
})
})
return
}
func (db *DB) initCountries() (err error) {
db.countriesOnce.Do(func() {
db.mCountries = make(map[string]string)
err = db.scanWords(db.countries, countryFldNum, func(words []string) error {
db.mCountries[words[countryName]] = words[countryISOCode]
return nil
})
})
return
}
var errScanInt = errors.New("interrupt scan")
func (db *DB) scanWords(pm pathMode, num int, wordsHandler func([]string) error) error {
tableFile, err := os.OpenFile(pm.path, os.O_RDONLY, pm.mode)
if err != nil {
return err
}
defer tableFile.Close()
r := csv.NewReader(tableFile)
r.ReuseRecord = true
for {
words, err := r.Read()
if err != nil {
if errors.Is(err, io.EOF) {
break
}
return err
} else if ln := len(words); ln != num {
return fmt.Errorf("unexpected number of words %d", ln)
}
if err := wordsHandler(words); err != nil {
if errors.Is(err, errScanInt) {
break
}
return err
}
}
return nil
}