Google Git
Sign in
fuchsia / third_party / goleveldb / 52ea2dd038a560e2a5a69403fb759ca8a8968257
commit52ea2dd038a560e2a5a69403fb759ca8a8968257[log] [tgz]
authorJustin Mattson <jmatt@google.com>Wed Apr 05 14:16:03 2017 -0700
committerJustin Mattson <jmatt@google.com>Fri Apr 07 13:37:49 2017 -0700
treef20ecebe97f43c1de251ccaa7a6259710fd3db77
parent3c5717caf1475fd25964109a0fc640bd150fce43 [diff]
Add file storage adapter for Fuchsia

This skips calls to flock, since we don't support that syscall,
we should replace this with some other sort of lock if we can.

Change-Id: I19d8317beb96d081e5ecec3ad876ffd7d0164c58
1 file changed
tree: f20ecebe97f43c1de251ccaa7a6259710fd3db77
  1. leveldb/
  2. manualtest/
  3. .travis.yml
  4. LICENSE
  5. README.md
README.md

This is an implementation of the LevelDB key/value database in the Go programming language.

Build Status

Installation

go get github.com/syndtr/goleveldb/leveldb

Requirements

  • Need at least go1.4 or newer.

Usage

Create or open a database:

db, err := leveldb.OpenFile("path/to/db", nil)
...
defer db.Close()
...

Read or modify the database content:

// Remember that the contents of the returned slice should not be modified.
data, err := db.Get([]byte("key"), nil)
...
err = db.Put([]byte("key"), []byte("value"), nil)
...
err = db.Delete([]byte("key"), nil)
...

Iterate over database content:

iter := db.NewIterator(nil, nil)
for iter.Next() {
	// Remember that the contents of the returned slice should not be modified, and
	// only valid until the next call to Next.
	key := iter.Key()
	value := iter.Value()
	...
}
iter.Release()
err = iter.Error()
...

Seek-then-Iterate:

iter := db.NewIterator(nil, nil)
for ok := iter.Seek(key); ok; ok = iter.Next() {
	// Use key/value.
	...
}
iter.Release()
err = iter.Error()
...

Iterate over subset of database content:

iter := db.NewIterator(&util.Range{Start: []byte("foo"), Limit: []byte("xoo")}, nil)
for iter.Next() {
	// Use key/value.
	...
}
iter.Release()
err = iter.Error()
...

Iterate over subset of database content with a particular prefix:

iter := db.NewIterator(util.BytesPrefix([]byte("foo-")), nil)
for iter.Next() {
	// Use key/value.
	...
}
iter.Release()
err = iter.Error()
...

Batch writes:

batch := new(leveldb.Batch)
batch.Put([]byte("foo"), []byte("value"))
batch.Put([]byte("bar"), []byte("another value"))
batch.Delete([]byte("baz"))
err = db.Write(batch, nil)
...

Use bloom filter:

o := &opt.Options{
	Filter: filter.NewBloomFilter(10),
}
db, err := leveldb.OpenFile("path/to/db", o)
...
defer db.Close()
...

Documentation

You can read package documentation here.