components-contrib/state/cassandra/cassandra.go

312 lines
8.5 KiB
Go

/*
Copyright 2021 The Dapr Authors
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 cassandra
import (
"context"
"fmt"
"reflect"
"strconv"
"github.com/gocql/gocql"
jsoniter "github.com/json-iterator/go"
"github.com/dapr/components-contrib/metadata"
"github.com/dapr/components-contrib/state"
stateutils "github.com/dapr/components-contrib/state/utils"
"github.com/dapr/kit/logger"
)
const (
hosts = "hosts"
port = "port"
username = "username"
password = "password"
protoVersion = "protoVersion"
consistency = "consistency"
table = "table"
keyspace = "keyspace"
replicationFactor = "replicationFactor"
defaultProtoVersion = 4
defaultReplicationFactor = 1
defaultConsistency = gocql.All
defaultTable = "items"
defaultKeyspace = "dapr"
defaultPort = 9042
metadataTTLKey = "ttlInSeconds"
)
// Cassandra is a state store implementation for Apache Cassandra.
type Cassandra struct {
state.DefaultBulkStore
session *gocql.Session
cluster *gocql.ClusterConfig
table string
logger logger.Logger
}
type cassandraMetadata struct {
Hosts []string
Port int
ProtoVersion int
ReplicationFactor int
Username string
Password string
Consistency string
Table string
Keyspace string
}
// NewCassandraStateStore returns a new cassandra state store.
func NewCassandraStateStore(logger logger.Logger) state.Store {
s := &Cassandra{logger: logger}
s.DefaultBulkStore = state.NewDefaultBulkStore(s)
return s
}
// Init performs metadata and connection parsing.
func (c *Cassandra) Init(metadata state.Metadata) error {
meta, err := getCassandraMetadata(metadata)
if err != nil {
return err
}
cluster, err := c.createClusterConfig(meta)
if err != nil {
return fmt.Errorf("error creating cluster config: %s", err)
}
c.cluster = cluster
session, err := cluster.CreateSession()
if err != nil {
return fmt.Errorf("error creating session: %s", err)
}
c.session = session
err = c.tryCreateKeyspace(meta.Keyspace, meta.ReplicationFactor)
if err != nil {
return fmt.Errorf("error creating keyspace %s: %s", meta.Keyspace, err)
}
err = c.tryCreateTable(meta.Table, meta.Keyspace)
if err != nil {
return fmt.Errorf("error creating table %s: %s", meta.Table, err)
}
c.table = fmt.Sprintf("%s.%s", meta.Keyspace, meta.Table)
return nil
}
// Features returns the features available in this state store.
func (c *Cassandra) Features() []state.Feature {
return nil
}
func (c *Cassandra) tryCreateKeyspace(keyspace string, replicationFactor int) error {
return c.session.Query(fmt.Sprintf("CREATE KEYSPACE IF NOT EXISTS %s WITH REPLICATION = {'class' : 'SimpleStrategy', 'replication_factor' : %s};", keyspace, fmt.Sprintf("%v", replicationFactor))).Exec()
}
func (c *Cassandra) tryCreateTable(table, keyspace string) error {
return c.session.Query(fmt.Sprintf("CREATE TABLE IF NOT EXISTS %s.%s (key text, value blob, PRIMARY KEY (key));", keyspace, table)).Exec()
}
func (c *Cassandra) createClusterConfig(metadata *cassandraMetadata) (*gocql.ClusterConfig, error) {
clusterConfig := gocql.NewCluster(metadata.Hosts...)
if metadata.Username != "" && metadata.Password != "" {
clusterConfig.Authenticator = gocql.PasswordAuthenticator{Username: metadata.Username, Password: metadata.Password}
}
clusterConfig.Port = metadata.Port
clusterConfig.ProtoVersion = metadata.ProtoVersion
cons, err := c.getConsistency(metadata.Consistency)
if err != nil {
return nil, err
}
clusterConfig.Consistency = cons
return clusterConfig, nil
}
func (c *Cassandra) getConsistency(consistency string) (gocql.Consistency, error) {
switch consistency {
case "All":
return gocql.All, nil
case "One":
return gocql.One, nil
case "Two":
return gocql.Two, nil
case "Three":
return gocql.Three, nil
case "Quorum":
return gocql.Quorum, nil
case "LocalQuorum":
return gocql.LocalQuorum, nil
case "EachQuorum":
return gocql.EachQuorum, nil
case "LocalOne":
return gocql.LocalOne, nil
case "Any":
return gocql.Any, nil
case "":
return defaultConsistency, nil
}
return 0, fmt.Errorf("consistency mode %s not found", consistency)
}
func getCassandraMetadata(meta state.Metadata) (*cassandraMetadata, error) {
m := cassandraMetadata{
ProtoVersion: defaultProtoVersion,
Table: defaultTable,
Keyspace: defaultKeyspace,
ReplicationFactor: defaultReplicationFactor,
Consistency: "All",
Port: defaultPort,
}
err := metadata.DecodeMetadata(meta.Properties, &m)
if err != nil {
return nil, err
}
if m.Hosts == nil || len(m.Hosts) == 0 {
return nil, fmt.Errorf("missing or empty hosts field from metadata")
}
if val, ok := meta.Properties[port]; ok && val != "" {
p, err := strconv.ParseInt(val, 0, 32)
if err != nil {
return nil, fmt.Errorf("error parsing port field: %s", err)
}
m.Port = int(p)
}
if val, ok := meta.Properties[protoVersion]; ok && val != "" {
p, err := strconv.ParseInt(val, 0, 32)
if err != nil {
return nil, fmt.Errorf("error parsing protoVersion field: %s", err)
}
m.ProtoVersion = int(p)
}
if val, ok := meta.Properties[replicationFactor]; ok && val != "" {
r, err := strconv.ParseInt(val, 0, 32)
if err != nil {
return nil, fmt.Errorf("error parsing replicationFactor field: %s", err)
}
m.ReplicationFactor = int(r)
}
return &m, nil
}
// Delete performs a delete operation.
func (c *Cassandra) Delete(ctx context.Context, req *state.DeleteRequest) error {
return c.session.Query(fmt.Sprintf("DELETE FROM %s WHERE key = ?", c.table), req.Key).WithContext(ctx).Exec()
}
// Get retrieves state from cassandra with a key.
func (c *Cassandra) Get(ctx context.Context, req *state.GetRequest) (*state.GetResponse, error) {
session := c.session
if req.Options.Consistency == state.Strong {
sess, err := c.createSession(gocql.All)
if err != nil {
return nil, err
}
defer sess.Close()
session = sess
} else if req.Options.Consistency == state.Eventual {
sess, err := c.createSession(gocql.One)
if err != nil {
return nil, err
}
defer sess.Close()
session = sess
}
results, err := session.Query(fmt.Sprintf("SELECT value FROM %s WHERE key = ?", c.table), req.Key).WithContext(ctx).Iter().SliceMap()
if err != nil {
return nil, err
}
if len(results) == 0 {
return &state.GetResponse{}, nil
}
return &state.GetResponse{
Data: results[0]["value"].([]byte),
}, nil
}
// Set saves state into cassandra.
func (c *Cassandra) Set(ctx context.Context, req *state.SetRequest) error {
var bt []byte
b, ok := req.Value.([]byte)
if ok {
bt = b
} else {
bt, _ = jsoniter.ConfigFastest.Marshal(req.Value)
}
session := c.session
if req.Options.Consistency == state.Strong {
sess, err := c.createSession(gocql.Quorum)
if err != nil {
return err
}
defer sess.Close()
session = sess
} else if req.Options.Consistency == state.Eventual {
sess, err := c.createSession(gocql.Any)
if err != nil {
return err
}
defer sess.Close()
session = sess
}
ttl, err := stateutils.ParseTTL(req.Metadata)
if err != nil {
return fmt.Errorf("error parsing TTL from Metadata: %s", err)
}
if ttl != nil {
return session.Query(fmt.Sprintf("INSERT INTO %s (key, value) VALUES (?, ?) USING TTL ?", c.table), req.Key, bt, *ttl).WithContext(ctx).Exec()
}
return session.Query(fmt.Sprintf("INSERT INTO %s (key, value) VALUES (?, ?)", c.table), req.Key, bt).WithContext(ctx).Exec()
}
func (c *Cassandra) createSession(consistency gocql.Consistency) (*gocql.Session, error) {
session, err := c.cluster.CreateSession()
if err != nil {
return nil, fmt.Errorf("error creating session: %s", err)
}
session.SetConsistency(consistency)
return session, nil
}
func (c *Cassandra) GetComponentMetadata() map[string]string {
metadataStruct := cassandraMetadata{}
metadataInfo := map[string]string{}
metadata.GetMetadataInfoFromStructType(reflect.TypeOf(metadataStruct), &metadataInfo)
return metadataInfo
}