yvbolt/bolt.go

196 lines
4.4 KiB
Go

package main
import (
"fmt"
"path/filepath"
"sort"
"strings"
"time"
"unsafe"
"github.com/ying32/govcl/vcl"
"github.com/ying32/govcl/vcl/types"
"go.etcd.io/bbolt"
"go.etcd.io/bbolt/version"
)
type boltLoadedDatabase struct {
displayName string
path string
db *bbolt.DB
nav *vcl.TTreeNode
arena []*navData // keepalive
}
func (ld *boltLoadedDatabase) DisplayName() string {
return ld.displayName
}
func (ld *boltLoadedDatabase) DriverName() string {
return "Bolt " + version.Version
}
func (ld *boltLoadedDatabase) RootElement() *vcl.TTreeNode {
return ld.nav
}
func (ld *boltLoadedDatabase) Keepalive(ndata *navData) {
ld.arena = append(ld.arena, ndata)
}
func (ld *boltLoadedDatabase) RenderForNav(f *TMainForm, ndata *navData) {
// Load properties
bucketDisplayName := strings.Join(ndata.bucketPath, `/`)
content := fmt.Sprintf("Selected database: %#v\n\n\nSelected bucket: %q\n", ld.db.Stats(), bucketDisplayName)
f.propertiesBox.SetText(content)
// Load data
f.contentBox.SetEnabled(false)
f.contentBox.Clear()
// Bolt always uses Key + Value as the columns
f.contentBox.Columns().Clear()
colKey := f.contentBox.Columns().Add()
colKey.SetCaption("Key")
colKey.SetWidth(MY_WIDTH)
colKey.SetAlignment(types.TaLeftJustify)
colVal := f.contentBox.Columns().Add()
colVal.SetCaption("Value")
err := ld.db.View(func(tx *bbolt.Tx) error {
b := boltTargetBucket(tx, ndata.bucketPath)
if b == nil {
// no such bucket
return nil
}
// Valid
f.contentBox.Clear()
c := b.Cursor()
for k, v := c.First(); k != nil; k, v = c.Next() {
dataEntry := f.contentBox.Items().Add()
dataEntry.SetCaption(formatUtf8(k))
dataEntry.SubItems().Add(formatUtf8(v))
}
return nil
})
if err != nil {
vcl.ShowMessage(fmt.Sprintf("Failed to load data for bucket %q: %s", bucketDisplayName, err.Error()))
return
}
// Valid
f.contentBox.SetEnabled(true)
}
func (ld *boltLoadedDatabase) NavChildren(ndata *navData) ([]string, error) {
// In the bolt implementation, the nav is a recursive tree of child buckets
return boltChildBucketNames(ld.db, ndata.bucketPath)
}
var _ loadedDatabase = &boltLoadedDatabase{} // interface assertion
//
func (f *TMainForm) boltAddDatabaseFromFile(path string) {
// TODO load in background thread to stop blocking the UI
db, err := bbolt.Open(path, 0644, &bbolt.Options{Timeout: 1 * time.Second})
if err != nil {
vcl.ShowMessage(fmt.Sprintf("Failed to load database '%s': %s", path, err.Error()))
return
}
ld := &boltLoadedDatabase{
path: path,
displayName: filepath.Base(path),
db: db,
}
ld.nav = f.Buckets.Items().Add(nil, ld.displayName)
ld.nav.SetHasChildren(true) // dynamically populate in OnNavExpanding
ld.nav.SetImageIndex(imgDatabase)
navData := &navData{
ld: ld,
childrenLoaded: false, // will be loaded dynamically
bucketPath: []string{}, // empty = root
}
ld.nav.SetData(unsafe.Pointer(navData))
f.dbs = append(f.dbs, ld)
ld.Keepalive(navData)
}
func boltTargetBucket(tx *bbolt.Tx, path []string) *bbolt.Bucket {
// If we are already deep in buckets, go directly there to find children
if len(path) == 0 {
return nil
}
b := tx.Bucket([]byte(path[0]))
if b == nil {
return nil // unexpectedly missing
}
for i := 1; i < len(path); i += 1 {
b = b.Bucket([]byte(path[i]))
if b == nil {
return nil // unexpectedly missing
}
}
return b // OK
}
func boltChildBucketNames(db *bbolt.DB, path []string) ([]string, error) {
var nextBucketNames []string
err := db.View(func(tx *bbolt.Tx) error {
// If we are already deep in buckets, go directly there to find children
if len(path) > 0 {
b := tx.Bucket([]byte(path[0]))
if b == nil {
return fmt.Errorf("Unexpected missing root bucket %q", path[0])
}
for i := 1; i < len(path); i += 1 {
b = b.Bucket([]byte(path[i]))
if b == nil {
return fmt.Errorf("Unexpected missing bucket %q", strings.Join(path[0:i], `/`))
}
}
// Find child buckets of this bucket
b.ForEachBucket(func(bucketName []byte) error {
nextBucketNames = append(nextBucketNames, string(bucketName))
return nil
})
} else {
// Find root bucket names
return tx.ForEach(func(bucketName []byte, _ *bbolt.Bucket) error {
nextBucketNames = append(nextBucketNames, string(bucketName))
return nil
})
}
// OK
return nil
})
if err != nil {
return nil, err
}
sort.Strings(nextBucketNames)
return nextBucketNames, nil
}