VOL-4019: Initial commit with grpc nbi, sbi, etcd, kafka and hw management rpcs.

Change-Id: I78feaf7da284028fc61f42c5e0c5f56e72fe9e78
diff --git a/pkg/models/device/db.go b/pkg/models/device/db.go
new file mode 100644
index 0000000..a98213e
--- /dev/null
+++ b/pkg/models/device/db.go
@@ -0,0 +1,191 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+ *
+ * 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 modifiablecomponent stores ModifiableComponent methods and functions
+package device
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+
+	"github.com/opencord/device-management-interface/go/dmi"
+
+	"github.com/opencord/voltha-lib-go/v4/pkg/log"
+
+	"github.com/opencord/opendevice-manager/pkg/db"
+
+	copy "github.com/jinzhu/copier"
+)
+
+// DBGetByName func reads device record by name
+func DBGetByName(ctx context.Context, name string) (*DeviceRecord, error) {
+	if name == "" {
+		logger.Errorw(ctx, "DBGetByName-failed-missing-device-name", log.Fields{})
+		return nil, errors.New("name field is empty")
+	}
+
+	logger.Debugw(ctx, "DBGetByName-invoked", log.Fields{"name": name})
+	defer logger.Debugw(ctx, "DBGetByName-completed", log.Fields{"name": name})
+
+	if val, ok := cache.nameToRec.Load(name); ok {
+		return val.(*DeviceRecord), nil
+	}
+
+	key := fmt.Sprintf(DbPathNameToRecord, name)
+	entry, err := db.Read(ctx, key)
+	if err != nil {
+		logger.Errorw(ctx, "DBGetByName-failed-read-db", log.Fields{"error": err, "key": key})
+		return nil, err
+	}
+
+	rec := new(DeviceRecord)
+	if err = json.Unmarshal([]byte(entry), rec); err != nil {
+		logger.Errorw(ctx, "Failed-to-unmarshal-at-DBGetByName", log.Fields{"reason": err, "entry": entry})
+		return nil, err
+	}
+
+	cache.nameToRec.Store(name, rec)
+
+	return rec, nil
+}
+
+// DBGetByUuid func reads device record by Uuid
+func DBGetByUuid(ctx context.Context, uuid string) (*DeviceRecord, error) {
+
+	if uuid == "" {
+		logger.Errorw(ctx, "DBGetByUuid-failed-missing-device-uuid", log.Fields{})
+		return nil, errors.New("uuid field is empty")
+	}
+
+	logger.Debugw(ctx, "DBGetByUuid-invoked", log.Fields{"uuid": uuid})
+	defer logger.Debugw(ctx, "DBGetByUuid-completed", log.Fields{"uuid": uuid})
+
+	var name string
+	var err error
+
+	if val, ok := cache.uuidToName.Load(uuid); ok {
+		name = val.(string)
+	} else {
+
+		key := fmt.Sprintf(DbPathUuidToName, uuid)
+		name, err = db.Read(ctx, key)
+		if err != nil {
+			logger.Errorw(ctx, "DBGetByUuid-failed-read-db", log.Fields{"error": err, "key": key})
+			return nil, err
+		}
+	}
+
+	cache.uuidToName.Store(uuid, name)
+
+	return DBGetByName(ctx, name)
+}
+
+// DBGetAll func returns all device records
+func DBGetAll(ctx context.Context) ([]*DeviceRecord, error) {
+	key := fmt.Sprintf(DbPathNameToRecord, "")
+	kvPairs, err := db.ReadAll(ctx, key)
+	if err != nil {
+		logger.Errorw(ctx, "DBGetAll-failed-read-db", log.Fields{"error": err, "key": key})
+		return nil, err
+	}
+
+	var listDevs []*DeviceRecord
+
+	for _, entry := range kvPairs {
+		rec := new(DeviceRecord)
+		if err = json.Unmarshal([]byte(entry), rec); err != nil {
+			logger.Errorw(ctx, "Failed-to-unmarshal-at-DBGetByName", log.Fields{"reason": err, "entry": entry})
+		} else {
+			listDevs = append(listDevs, rec)
+		}
+	}
+
+	logger.Infow(ctx, "DBGetAll-success", log.Fields{"entry": listDevs})
+
+	return listDevs, nil
+}
+
+// DBAddByName inserts Device Info record to DB with Name as Key
+func (rec *DeviceRecord) DBAddByName(ctx context.Context) error {
+	if rec.Name == "" {
+		logger.Errorw(ctx, "DBAddByName-failed-missing-device-name", log.Fields{"rec": rec})
+		return errors.New("missing name")
+	}
+	key := fmt.Sprintf(DbPathNameToRecord, rec.Name)
+	b, _ := json.Marshal(rec)
+	entry := string(b)
+	err := db.Put(ctx, key, entry)
+	cache.nameToRec.Store(rec.Name, rec)
+	logger.Infow(ctx, "Inserting-device-info-to-Db-in-DBAddByName-method", log.Fields{"rec": rec, "error": err})
+	return err
+}
+
+// DBAddUuidLookup creates a lookup of name from uuid
+func (rec *DeviceRecord) DBAddUuidLookup(ctx context.Context) error {
+	if rec.Uuid == "" || rec.Name == "" {
+		logger.Errorw(ctx, "DBAddUuidLookup-failed-missing-device-name-or-uuid", log.Fields{"rec": rec})
+		return errors.New("missing name")
+	}
+	key := fmt.Sprintf(DbPathUuidToName, rec.Uuid)
+	err := db.Put(ctx, key, rec.Name)
+	cache.uuidToName.Store(rec.Uuid, rec.Name)
+	logger.Infow(ctx, "DBAddUuidLookup-success", log.Fields{"rec": rec, "error": err})
+	return err
+}
+
+// DBDelRecord deletes all entries for Device Info
+func (rec *DeviceRecord) DBDelRecord(ctx context.Context) error {
+
+	var err error
+
+	if rec.Name != "" {
+		key := fmt.Sprintf(DbPathNameToRecord, rec.Name)
+		logger.Infow(ctx, "deleting-device-info-record-using-name", log.Fields{"name": rec.Name, "key": key})
+		err = db.Del(ctx, key)
+		cache.nameToRec.Delete(rec.Name)
+	}
+
+	if err == nil && rec.Uuid != "" {
+		key := fmt.Sprintf(DbPathUuidToName, rec.Uuid)
+		logger.Infow(ctx, "deleting-device-info-record-using-uuid", log.Fields{"uuid": rec.Uuid, "key": key})
+		err = db.Del(ctx, key)
+		cache.uuidToName.Delete(rec.Uuid)
+	}
+
+	return err
+}
+
+// DBSaveHwInfo stores hardware copies info from response and stores in db
+func (rec *DeviceRecord) DBSaveHwInfo(ctx context.Context, hw *dmi.Hardware) error {
+	defer logger.Infow(ctx, "saving-hw-info-to-device-record-completed", log.Fields{"rec": rec})
+	rec.LastBooted = hw.LastBooted
+	rec.LastChange = hw.LastChange
+	name := rec.Name
+	uuid := rec.Uuid
+	if err := copy.Copy(&rec, &hw.Root); err != nil {
+		logger.Errorw(ctx, "copy-failed-at-DBSaveHwInfo", log.Fields{"rec": rec, "error": err, "hw": hw})
+		return err
+	}
+	rec.Children = []string{}
+	for _, child := range hw.Root.Children {
+		rec.Children = append(rec.Children, child.Uuid.Uuid)
+	}
+	rec.Name = name
+	rec.Uuid = uuid
+	return rec.DBAddByName(ctx)
+}