frostfs-node/pkg/util/locode/db/airports/db.go

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package airportsdb
import (
"fmt"
"os"
"sync"
)
// Prm groups the required parameters of the DB's constructor.
//
// All values must comply with the requirements imposed on them.
// Passing incorrect parameter values will result in constructor
// failure (error or panic depending on the implementation).
type Prm struct {
// Path to OpenFlights Airport csv table.
//
// Must not be empty.
AirportsPath string
// Path to OpenFlights Countries csv table.
//
// Must not be empty.
CountriesPath string
}
// DB is a descriptor of the OpenFlights database in csv format.
//
// For correct operation, DB must be created
// using the constructor (New) based on the required parameters
// and optional components. After successful creation,
// The DB is immediately ready to work through API.
type DB struct {
airports, countries pathMode
airportsOnce, countriesOnce sync.Once
mCountries map[string]string
mAirports map[string][]record
}
type pathMode struct {
path string
mode os.FileMode
}
const invalidPrmValFmt = "invalid parameter %s (%T):%v"
func panicOnPrmValue(n string, v interface{}) {
panic(fmt.Sprintf(invalidPrmValFmt, n, v, v))
}
// New creates a new instance of the DB.
//
// Panics if at least one value of the parameters is invalid.
//
// The created DB does not require additional
// initialization and is completely ready for work.
func New(prm Prm, opts ...Option) *DB {
switch {
case prm.AirportsPath == "":
panicOnPrmValue("AirportsPath", prm.AirportsPath)
case prm.CountriesPath == "":
panicOnPrmValue("CountriesPath", prm.CountriesPath)
}
o := defaultOpts()
for i := range opts {
opts[i](o)
}
return &DB{
airports: pathMode{
path: prm.AirportsPath,
mode: o.airportMode,
},
countries: pathMode{
path: prm.CountriesPath,
mode: o.countryMode,
},
}
}