pm/remote/remote.go
2018-03-02 23:23:11 -08:00

151 lines
2.6 KiB
Go

package remote
import (
"encoding/json"
"fmt"
"io"
"net/url"
"os"
"path/filepath"
"github.com/pkg/errors"
"mcquay.me/fs"
)
// DB is a slice of available URI
type DB []url.URL
const rn = "var/lib/pm/remotes.json"
// Add appends the provided uri to the list of configured remotes.
func Add(root string, uris []string) error {
db, err := load(root)
if err != nil {
return errors.Wrap(err, "loading")
}
dbm := map[string]bool{}
for _, u := range db {
dbm[u.String()] = true
}
for _, uri := range uris {
pu, err := url.Parse(uri)
if err != nil {
return errors.Wrap(err, "url parse")
}
u := strip(*pu)
if _, ok := dbm[u.String()]; ok {
return fmt.Errorf("%q already in db", u.String())
}
db = append(db, u)
}
return save(root, db)
}
// Remove removes the given uri from the list of configured remotes.
func Remove(root string, uris []string) error {
db, err := load(root)
if err != nil {
return errors.Wrap(err, "loading")
}
rms := map[string]bool{}
for _, uri := range uris {
pu, err := url.Parse(uri)
if err != nil {
return errors.Wrap(err, "url parse")
}
u := strip(*pu)
rms[u.String()] = true
}
o := DB{}
for _, d := range db {
if _, ok := rms[d.String()]; !ok {
o = append(o, d)
}
}
if len(o) == len(db) {
return errors.New("found no matching remotes")
}
return save(root, o)
}
// List prints all configured remotes to w.
func List(root string, w io.Writer) error {
db, err := load(root)
if err != nil {
return errors.Wrap(err, "loading")
}
for _, u := range db {
fmt.Fprintf(w, "%s\n", u.String())
}
return nil
}
func load(root string) (DB, error) {
r := DB{}
dbn := filepath.Join(root, rn)
if !fs.Exists(dbn) {
return r, nil
}
f, err := os.Open(filepath.Join(root, rn))
if err != nil {
return r, errors.Wrap(err, "open")
}
if err := json.NewDecoder(f).Decode(&r); err != nil {
return r, errors.Wrap(err, "decoding db")
}
return r, nil
}
func save(root string, db DB) error {
f, err := os.Create(filepath.Join(root, rn))
if err != nil {
return errors.Wrap(err, "create")
}
enc := json.NewEncoder(f)
enc.SetIndent("", "\t")
if err := enc.Encode(&db); err != nil {
return errors.Wrap(err, "decoding db")
}
if err := f.Close(); err != nil {
return errors.Wrap(err, "close db")
}
return nil
}
// strip removes all fields we don't currently need.
func strip(u url.URL) url.URL {
return url.URL{
Scheme: u.Scheme,
Host: u.Host,
Path: u.Path,
}
}
func mkdirs(root string) error {
d, _ := filepath.Split(filepath.Join(root, rn))
if !fs.Exists(d) {
if err := os.MkdirAll(d, 0700); err != nil {
return errors.Wrap(err, "mk pm dir")
}
}
return nil
}