Add base skeleton for rocksdb bindings

rocksdb/db.go

@@ -0,0 +1,59 @@
+/*
+   Copyright 2018 Banco Bilbao Vizcaya Argentaria, S.A.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package rocksdb
+
+// #cgo LDFLAGS: -L../c-deps/rocksdb/
+// #cgo LDFLAGS: -lrocksdb
+// #include "../c-deps/rocksdb/include/rocksdb/c.h"
+// #include <stdlib.h>
+import "C"
+import (
+	"errors"
+	"unsafe"
+)
+
+// DB is a reusable handler to a RocksDB database on disk, created by Open.
+type DB struct {
+	db   *C.rocksdb_t
+	opts *Options
+}
+
+func Open(path string, opts *Options) (*DB, error) {
+	var cErr *C.char
+	var cPath = C.CString(path)
+	defer C.free(unsafe.Pointer(cPath))
+
+	db := C.rocksdb_open(opts.opts, cPath, &cErr)
+	if cErr != nil {
+		defer C.free(unsafe.Pointer(cErr))
+		return nil, errors.New(C.GoString(cErr))
+	}
+
+	return &DB{
+		db:   db,
+		opts: opts,
+	}, nil
+}
+
+func (db *DB) Close() error {
+	if db.db != nil {
+		C.rocksdb_close(db.db)
+		db.db = nil
+	}
+	db.opts.Destroy()
+	return nil
+}

rocksdb/db_test.go

@@ -0,0 +1,45 @@
+/*
+   Copyright 2018 Banco Bilbao Vizcaya Argentaria, S.A.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package rocksdb
+
+import (
+	"io/ioutil"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestOpenDB(t *testing.T) {
+	db := newTestDB(t, "TestOpenDB", nil)
+	defer db.Close()
+}
+
+func newTestDB(t *testing.T, name string, applyOpts func(opts *Options)) *DB {
+	dir, err := ioutil.TempDir("", "rocksdb-"+name)
+	require.NoError(t, err)
+
+	opts := NewDefaultOptions()
+	opts.SetCreateIfMissing(true)
+	if applyOpts != nil {
+		applyOpts(opts)
+	}
+
+	db, err := Open(dir, opts)
+	require.NoError(t, err)
+
+	return db
+}

rocksdb/options.go

@@ -0,0 +1,55 @@
+/*
+   Copyright 2018 Banco Bilbao Vizcaya Argentaria, S.A.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package rocksdb
+
+// #cgo LDFLAGS: -L../c-deps/rocksdb/
+// #cgo LDFLAGS: -lrocksdb
+// #include "../c-deps/rocksdb/include/rocksdb/c.h"
+import "C"
+
+type CompressionType uint
+
+// Compression types
+const (
+	NoCompression     = CompressionType(C.rocksdb_no_compression)
+	SnappyCompression = CompressionType(C.rocksdb_snappy_compression)
+)
+
+// Options represent all of the available options when opening a database with Open.
+type Options struct {
+	opts *C.rocksdb_options_t
+}
+
+func NewDefaultOptions() *Options {
+	return NewNativeOptions(C.rocksdb_options_create())
+}
+
+func NewNativeOptions(opts *C.rocksdb_options_t) *Options {
+	return &Options{opts: opts}
+}
+
+// SetCreateIfMissing specifies whether the database
+// should be created if it is missing.
+// Default: false
+func (o *Options) SetCreateIfMissing(value bool) {
+	C.rocksdb_options_set_create_if_missing(o.opts, boolToUchar(value))
+}
+
+func (o *Options) Destroy() {
+	C.rocksdb_options_destroy(o.opts)
+	o.opts = nil
+}

rocksdb/util.go

@@ -0,0 +1,28 @@
+/*
+   Copyright 2018 Banco Bilbao Vizcaya Argentaria, S.A.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package rocksdb
+
+// #include <stdlib.h>
+import "C"
+
+// boolToUchar converts a bool value to C.uchar.
+func boolToUchar(b bool) C.uchar {
+	if b {
+		return C.uchar(1)
+	}
+	return C.uchar(0)
+}