lnd.xprv/channeldb/migration_01_to_11/db.go
Olaoluwa Osuntokun f0911765af
channeldb: convert to uniformly use new kvdb abstractions
In this commit, we migrate all the code in `channeldb` to only reference
the new `kvdb` package rather than `bbolt` directly.

In many instances, we need to add two version to fetch a bucket as both
read and write when needed. As an example, we add a new
`fetchChanBucketRw` function. This function is identical to
`fetchChanBucket`, but it will be used to fetch the main channel bucket
for all _write_ transactions. We need a new method as you can pass a
write transaction where a read is accepted, but not the other way around
due to the stronger typing of the new `kvdb` package.
2020-03-18 19:34:49 -07:00

217 lines
5.3 KiB
Go

package migration_01_to_11
import (
"bytes"
"encoding/binary"
"fmt"
"os"
"path/filepath"
"time"
"github.com/lightningnetwork/lnd/channeldb/kvdb"
)
const (
dbName = "channel.db"
dbFilePermission = 0600
)
// migration is a function which takes a prior outdated version of the database
// instances and mutates the key/bucket structure to arrive at a more
// up-to-date version of the database.
type migration func(tx kvdb.RwTx) error
var (
// Big endian is the preferred byte order, due to cursor scans over
// integer keys iterating in order.
byteOrder = binary.BigEndian
)
// DB is the primary datastore for the lnd daemon. The database stores
// information related to nodes, routing data, open/closed channels, fee
// schedules, and reputation data.
type DB struct {
kvdb.Backend
dbPath string
graph *ChannelGraph
now func() time.Time
}
// Open opens an existing channeldb. Any necessary schemas migrations due to
// updates will take place as necessary.
func Open(dbPath string, modifiers ...OptionModifier) (*DB, error) {
path := filepath.Join(dbPath, dbName)
if !fileExists(path) {
if err := createChannelDB(dbPath); err != nil {
return nil, err
}
}
opts := DefaultOptions()
for _, modifier := range modifiers {
modifier(&opts)
}
// Specify bbolt freelist options to reduce heap pressure in case the
// freelist grows to be very large.
bdb, err := kvdb.Open(kvdb.BoltBackendName, path, opts.NoFreelistSync)
if err != nil {
return nil, err
}
chanDB := &DB{
Backend: bdb,
dbPath: dbPath,
now: time.Now,
}
chanDB.graph = newChannelGraph(
chanDB, opts.RejectCacheSize, opts.ChannelCacheSize,
)
return chanDB, nil
}
// createChannelDB creates and initializes a fresh version of channeldb. In
// the case that the target path has not yet been created or doesn't yet exist,
// then the path is created. Additionally, all required top-level buckets used
// within the database are created.
func createChannelDB(dbPath string) error {
if !fileExists(dbPath) {
if err := os.MkdirAll(dbPath, 0700); err != nil {
return err
}
}
path := filepath.Join(dbPath, dbName)
bdb, err := kvdb.Create(kvdb.BoltBackendName, path, false)
if err != nil {
return err
}
err = kvdb.Update(bdb, func(tx kvdb.RwTx) error {
if _, err := tx.CreateTopLevelBucket(openChannelBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(closedChannelBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(invoiceBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(paymentBucket); err != nil {
return err
}
nodes, err := tx.CreateTopLevelBucket(nodeBucket)
if err != nil {
return err
}
_, err = nodes.CreateBucket(aliasIndexBucket)
if err != nil {
return err
}
_, err = nodes.CreateBucket(nodeUpdateIndexBucket)
if err != nil {
return err
}
edges, err := tx.CreateTopLevelBucket(edgeBucket)
if err != nil {
return err
}
if _, err := edges.CreateBucket(edgeIndexBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(edgeUpdateIndexBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(channelPointBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(zombieBucket); err != nil {
return err
}
graphMeta, err := tx.CreateTopLevelBucket(graphMetaBucket)
if err != nil {
return err
}
_, err = graphMeta.CreateBucket(pruneLogBucket)
if err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(metaBucket); err != nil {
return err
}
meta := &Meta{
DbVersionNumber: 0,
}
return putMeta(meta, tx)
})
if err != nil {
return fmt.Errorf("unable to create new channeldb")
}
return bdb.Close()
}
// fileExists returns true if the file exists, and false otherwise.
func fileExists(path string) bool {
if _, err := os.Stat(path); err != nil {
if os.IsNotExist(err) {
return false
}
}
return true
}
// FetchClosedChannels attempts to fetch all closed channels from the database.
// The pendingOnly bool toggles if channels that aren't yet fully closed should
// be returned in the response or not. When a channel was cooperatively closed,
// it becomes fully closed after a single confirmation. When a channel was
// forcibly closed, it will become fully closed after _all_ the pending funds
// (if any) have been swept.
func (d *DB) FetchClosedChannels(pendingOnly bool) ([]*ChannelCloseSummary, error) {
var chanSummaries []*ChannelCloseSummary
if err := kvdb.View(d, func(tx kvdb.ReadTx) error {
closeBucket := tx.ReadBucket(closedChannelBucket)
if closeBucket == nil {
return ErrNoClosedChannels
}
return closeBucket.ForEach(func(chanID []byte, summaryBytes []byte) error {
summaryReader := bytes.NewReader(summaryBytes)
chanSummary, err := deserializeCloseChannelSummary(summaryReader)
if err != nil {
return err
}
// If the query specified to only include pending
// channels, then we'll skip any channels which aren't
// currently pending.
if !chanSummary.IsPending && pendingOnly {
return nil
}
chanSummaries = append(chanSummaries, chanSummary)
return nil
})
}); err != nil {
return nil, err
}
return chanSummaries, nil
}
// ChannelGraph returns a new instance of the directed channel graph.
func (d *DB) ChannelGraph() *ChannelGraph {
return d.graph
}