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Replace Checkpoint with Store interface (#90)

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As we work towards introducing consumer groups to the repository we need a more generic name for the persistence layer for storing checkpoints and leases for given shards. 

* Rename `checkpoint` to `store`
This commit is contained in:
Harlow Ward 2019-07-28 21:18:40 -07:00 committed by GitHub
parent d05d6c2d5e
commit c72f561abd
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GPG key ID: 4AEE18F83AFDEB23
28 changed files with 134 additions and 129 deletions
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51
README.md
View file

@ -104,9 +104,13 @@ err := c.Scan(ctx, func(r *consumer.Record) error {
})
```
## Checkpoint
## Options
To record the progress of the consumer in the stream we use a checkpoint to store the last sequence number the consumer has read from a particular shard. The boolean value SkipCheckpoint of consumer.ScanError determines if checkpoint will be activated. ScanError is returned by the record processing callback.
The consumer allows the following optional overrides.
### Storage
To record the progress of the consumer in the stream (checkpoint) we use a storage layer to persist the last sequence number the consumer has read from a particular shard. The boolean value ErrSkipCheckpoint of consumer.ScanError determines if checkpoint will be activated. ScanError is returned by the record processing callback.
This will allow consumers to re-launch and pick up at the position in the stream where they left off.
@ -114,33 +118,42 @@ The uniq identifier for a consumer is `[appName, streamName, shardID]`
<img width="722" alt="kinesis-checkpoints" src="https://user-images.githubusercontent.com/739782/33085867-d8336122-ce9a-11e7-8c8a-a8afeb09dff1.png">
Note: The default checkpoint is no-op. Which means the scan will not persist any state and the consumer will start from the beginning of the stream each time it is re-started.
Note: The default storage is in-memory (no-op). Which means the scan will not persist any state and the consumer will start from the beginning of the stream each time it is re-started.
To persist scan progress choose one of the following checkpoints:
The consumer accpets a `WithStorage` option to set the storage layer:
### Redis Checkpoint
```go
c, err := consumer.New(*stream, consumer.WithStorage(db))
if err != nil {
log.Log("consumer error: %v", err)
}
```
To persist scan progress choose one of the following storage layers:
#### Redis
The Redis checkpoint requries App Name, and Stream Name:
```go
import checkpoint "github.com/harlow/kinesis-consumer/checkpoint/redis"
import storage "github.com/harlow/kinesis-consumer/store/redis"
// redis checkpoint
ck, err := checkpoint.New(appName)
db, err := storage.New(appName)
if err != nil {
log.Fatalf("new checkpoint error: %v", err)
}
```
### DynamoDB Checkpoint
#### DynamoDB
The DynamoDB checkpoint requires Table Name, App Name, and Stream Name:
```go
import checkpoint "github.com/harlow/kinesis-consumer/checkpoint/ddb"
import storage "github.com/harlow/kinesis-consumer/store/ddb"
// ddb checkpoint
ck, err := checkpoint.New(appName, tableName)
db, err := storage.New(appName, tableName)
if err != nil {
log.Fatalf("new checkpoint error: %v", err)
}
@ -154,7 +167,7 @@ myDynamoDbClient := dynamodb.New(session.New(aws.NewConfig()))
// Region: aws.String("us-west-2"),
// })
ck, err := checkpoint.New(*app, *table, checkpoint.WithDynamoClient(myDynamoDbClient))
db, err := storage.New(*app, *table, checkpoint.WithDynamoClient(myDynamoDbClient))
if err != nil {
log.Fatalf("new checkpoint error: %v", err)
}
@ -173,15 +186,15 @@ Sort key: shard_id
<img width="727" alt="screen shot 2017-11-22 at 7 59 36 pm" src="https://user-images.githubusercontent.com/739782/33158557-b90e4228-cfbf-11e7-9a99-73b56a446f5f.png">
### Postgres Checkpoint
#### Postgres
The Postgres checkpoint requires Table Name, App Name, Stream Name and ConnectionString:
```go
import checkpoint "github.com/harlow/kinesis-consumer/checkpoint/postgres"
import storage "github.com/harlow/kinesis-consumer/store/postgres"
// postgres checkpoint
ck, err := checkpoint.New(app, table, connStr)
db, err := storage.New(app, table, connStr)
if err != nil {
log.Fatalf("new checkpoint error: %v", err)
}
@ -201,15 +214,15 @@ CREATE TABLE kinesis_consumer (
The table name has to be the same that you specify when creating the checkpoint. The primary key composed by namespace and shard_id is mandatory in order to the checkpoint run without issues and also to ensure data integrity.
### Mysql Checkpoint
#### Mysql
The Mysql checkpoint requires Table Name, App Name, Stream Name and ConnectionString (just like the Postgres checkpoint!):
```go
import checkpoint "github.com/harlow/kinesis-consumer/checkpoint/mysql"
import storage "github.com/harlow/kinesis-consumer/store/mysql"
// mysql checkpoint
ck, err := checkpoint.New(app, table, connStr)
db, err := storage.New(app, table, connStr)
if err != nil {
log.Fatalf("new checkpoint error: %v", err)
}
@ -229,10 +242,6 @@ CREATE TABLE kinesis_consumer (
The table name has to be the same that you specify when creating the checkpoint. The primary key composed by namespace and shard_id is mandatory in order to the checkpoint run without issues and also to ensure data integrity.
## Options
The consumer allows the following optional overrides.
### Kinesis Client
Override the Kinesis client if there is any special config needed:

16
allgroup.go
View file

@ -11,13 +11,13 @@ import (
// NewAllGroup returns an intitialized AllGroup for consuming
// all shards on a stream
func NewAllGroup(ksis kinesisiface.KinesisAPI, ck Checkpoint, streamName string, logger Logger) *AllGroup {
func NewAllGroup(ksis kinesisiface.KinesisAPI, store Store, streamName string, logger Logger) *AllGroup {
return &AllGroup{
ksis: ksis,
shards: make(map[string]*kinesis.Shard),
streamName: streamName,
logger: logger,
checkpoint: ck,
Store: store,
}
}
@ -27,7 +27,7 @@ type AllGroup struct {
ksis kinesisiface.KinesisAPI
streamName string
logger Logger
checkpoint Checkpoint
Store
shardMu sync.Mutex
shards map[string]*kinesis.Shard
@ -59,16 +59,6 @@ func (g *AllGroup) Start(ctx context.Context, shardc chan *kinesis.Shard) {
}
}
// GetCheckpoint returns the current checkpoint for provided stream
func (g *AllGroup) GetCheckpoint(streamName, shardID string) (string, error) {
return g.checkpoint.Get(streamName, shardID)
}
// SetCheckpoint sets the current checkpoint for provided stream
func (g *AllGroup) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
return g.checkpoint.Set(streamName, shardID, sequenceNumber)
}
// findNewShards pulls the list of shards from the Kinesis API
// and uses a local cache to determine if we are already processing
// a particular shard.

13
checkpoint.go
View file

@ -1,13 +0,0 @@
package consumer
// Checkpoint interface used track consumer progress in the stream
type Checkpoint interface {
Get(streamName, shardID string) (string, error)
Set(streamName, shardID, sequenceNumber string) error
}
// noopCheckpoint implements the checkpoint interface with discard
type noopCheckpoint struct{}
func (n noopCheckpoint) Set(string, string, string) error { return nil }
func (n noopCheckpoint) Get(string, string) (string, error) { return "", nil }

16
consumer.go
View file

@ -23,12 +23,12 @@ func New(streamName string, opts ...Option) (*Consumer, error) {
return nil, fmt.Errorf("must provide stream name")
}
// new consumer with no-op checkpoint, counter, and logger
// new consumer with noop storage, counter, and logger
c := &Consumer{
streamName: streamName,
initialShardIteratorType: kinesis.ShardIteratorTypeLatest,
store: &noopStore{},
counter: &noopCounter{},
checkpoint: &noopCheckpoint{},
logger: &noopLogger{
logger: log.New(ioutil.Discard, "", log.LstdFlags),
},
@ -39,7 +39,7 @@ func New(streamName string, opts ...Option) (*Consumer, error) {
opt(c)
}
// default client if none provided
// default client
if c.client == nil {
newSession, err := session.NewSession(aws.NewConfig())
if err != nil {
@ -48,9 +48,9 @@ func New(streamName string, opts ...Option) (*Consumer, error) {
c.client = kinesis.New(newSession)
}
// default group if none provided
// default group consumes all shards
if c.group == nil {
c.group = NewAllGroup(c.client, c.checkpoint, c.streamName, c.logger)
c.group = NewAllGroup(c.client, c.store, streamName, c.logger)
}
return c, nil
@ -61,10 +61,10 @@ type Consumer struct {
streamName string
initialShardIteratorType string
client kinesisiface.KinesisAPI
logger Logger
group Group
checkpoint Checkpoint
counter Counter
group Group
logger Logger
store Store
}
// ScanFunc is the type of the function called for each message read

18
consumer_test.go
View file

@ -57,7 +57,7 @@ func TestScan(t *testing.T) {
c, err := New("myStreamName",
WithClient(client),
WithCounter(ctr),
WithCheckpoint(cp),
WithStorage(cp),
)
if err != nil {
t.Fatalf("new consumer error: %v", err)
@ -90,7 +90,7 @@ func TestScan(t *testing.T) {
t.Errorf("counter error expected %d, got %d", 2, val)
}
val, err := cp.Get("myStreamName", "myShard")
val, err := cp.GetCheckpoint("myStreamName", "myShard")
if err != nil && val != "lastSeqNum" {
t.Errorf("checkout error expected %s, got %s", "lastSeqNum", val)
}
@ -119,7 +119,7 @@ func TestScanShard(t *testing.T) {
c, err := New("myStreamName",
WithClient(client),
WithCounter(ctr),
WithCheckpoint(cp),
WithStorage(cp),
)
if err != nil {
t.Fatalf("new consumer error: %v", err)
@ -156,7 +156,7 @@ func TestScanShard(t *testing.T) {
}
// sets checkpoint
val, err := cp.Get("myStreamName", "myShard")
val, err := cp.GetCheckpoint("myStreamName", "myShard")
if err != nil && val != "lastSeqNum" {
t.Fatalf("checkout error expected %s, got %s", "lastSeqNum", val)
}
@ -219,7 +219,7 @@ func TestScanShard_SkipCheckpoint(t *testing.T) {
var cp = &fakeCheckpoint{cache: map[string]string{}}
c, err := New("myStreamName", WithClient(client), WithCheckpoint(cp))
c, err := New("myStreamName", WithClient(client), WithStorage(cp))
if err != nil {
t.Fatalf("new consumer error: %v", err)
}
@ -229,7 +229,7 @@ func TestScanShard_SkipCheckpoint(t *testing.T) {
var fn = func(r *Record) error {
if aws.StringValue(r.SequenceNumber) == "lastSeqNum" {
cancel()
return SkipCheckpoint
return ErrSkipCheckpoint
}
return nil
@ -240,7 +240,7 @@ func TestScanShard_SkipCheckpoint(t *testing.T) {
t.Fatalf("scan shard error: %v", err)
}
val, err := cp.Get("myStreamName", "myShard")
val, err := cp.GetCheckpoint("myStreamName", "myShard")
if err != nil && val != "firstSeqNum" {
t.Fatalf("checkout error expected %s, got %s", "firstSeqNum", val)
}
@ -301,7 +301,7 @@ type fakeCheckpoint struct {
mu sync.Mutex
}
func (fc *fakeCheckpoint) Set(streamName, shardID, sequenceNumber string) error {
func (fc *fakeCheckpoint) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
fc.mu.Lock()
defer fc.mu.Unlock()
@ -310,7 +310,7 @@ func (fc *fakeCheckpoint) Set(streamName, shardID, sequenceNumber string) error
return nil
}
func (fc *fakeCheckpoint) Get(streamName, shardID string) (string, error) {
func (fc *fakeCheckpoint) GetCheckpoint(streamName, shardID string) (string, error) {
fc.mu.Lock()
defer fc.mu.Unlock()

3
examples/consumer/cp-dynamo/README.md
View file

@ -7,9 +7,8 @@ Read records from the Kinesis stream
Export the required environment vars for connecting to the Kinesis stream:
```
export AWS_ACCESS_KEY=
export AWS_PROFILE=
export AWS_REGION=
export AWS_SECRET_KEY=
```
### Run the consumer

18
examples/consumer/cp-dynamo/main.go
View file

@ -19,7 +19,7 @@ import (
"github.com/aws/aws-sdk-go/service/dynamodb"
"github.com/aws/aws-sdk-go/service/kinesis"
consumer "github.com/harlow/kinesis-consumer"
checkpoint "github.com/harlow/kinesis-consumer/checkpoint/ddb"
storage "github.com/harlow/kinesis-consumer/store/ddb"
)
// kick off a server for exposing scan metrics
@ -69,8 +69,8 @@ func main() {
myKsis := kinesis.New(sess)
myDdbClient := dynamodb.New(sess)
// ddb checkpoint
ck, err := checkpoint.New(*app, *table, checkpoint.WithDynamoClient(myDdbClient), checkpoint.WithRetryer(&MyRetryer{}))
// ddb persitance
ddb, err := storage.New(*app, *table, storage.WithDynamoClient(myDdbClient), storage.WithRetryer(&MyRetryer{}))
if err != nil {
log.Log("checkpoint error: %v", err)
}
@ -81,7 +81,7 @@ func main() {
// consumer
c, err := consumer.New(
*stream,
consumer.WithCheckpoint(ck),
consumer.WithStorage(ddb),
consumer.WithLogger(log),
consumer.WithCounter(counter),
consumer.WithClient(myKsis),
@ -111,17 +111,17 @@ func main() {
log.Log("scan error: %v", err)
}
if err := ck.Shutdown(); err != nil {
log.Log("checkpoint shutdown error: %v", err)
if err := ddb.Shutdown(); err != nil {
log.Log("storage shutdown error: %v", err)
}
}
// MyRetryer used for checkpointing
// MyRetryer used for storage
type MyRetryer struct {
checkpoint.Retryer
storage.Retryer
}
// ShouldRetry implements custom logic for when a checkpont should retry
// ShouldRetry implements custom logic for when errors should retry
func (r *MyRetryer) ShouldRetry(err error) bool {
if awsErr, ok := err.(awserr.Error); ok {
switch awsErr.Code() {

3
examples/consumer/cp-mysql/README.md
View file

@ -7,9 +7,8 @@ Read records from the Kinesis stream using mysql as checkpoint
Export the required environment vars for connecting to the Kinesis stream:
```shell
export AWS_ACCESS_KEY=
export AWS_PROFILE=
export AWS_REGION=
export AWS_SECRET_KEY=
```
## Run the consumer

4
examples/consumer/cp-mysql/main.go
View file

@ -10,7 +10,7 @@ import (
"os/signal"
consumer "github.com/harlow/kinesis-consumer"
checkpoint "github.com/harlow/kinesis-consumer/checkpoint/mysql"
checkpoint "github.com/harlow/kinesis-consumer/store/mysql"
)
func main() {
@ -33,7 +33,7 @@ func main() {
// consumer
c, err := consumer.New(
*stream,
consumer.WithCheckpoint(ck),
consumer.WithStorage(ck),
consumer.WithCounter(counter),
)
if err != nil {

3
examples/consumer/cp-postgres/README.md
View file

@ -7,9 +7,8 @@ Read records from the Kinesis stream using postgres as checkpoint
Export the required environment vars for connecting to the Kinesis stream:
```shell
export AWS_ACCESS_KEY=
export AWS_PROFILE=
export AWS_REGION=
export AWS_SECRET_KEY=
```
## Run the consumer

4
examples/consumer/cp-postgres/main.go
View file

@ -10,7 +10,7 @@ import (
"os/signal"
consumer "github.com/harlow/kinesis-consumer"
checkpoint "github.com/harlow/kinesis-consumer/checkpoint/postgres"
checkpoint "github.com/harlow/kinesis-consumer/store/postgres"
)
func main() {
@ -33,7 +33,7 @@ func main() {
// consumer
c, err := consumer.New(
*stream,
consumer.WithCheckpoint(ck),
consumer.WithStorage(ck),
consumer.WithCounter(counter),
)
if err != nil {

4
examples/consumer/cp-redis/main.go
View file

@ -9,7 +9,7 @@ import (
"os/signal"
consumer "github.com/harlow/kinesis-consumer"
checkpoint "github.com/harlow/kinesis-consumer/checkpoint/redis"
checkpoint "github.com/harlow/kinesis-consumer/store/redis"
)
// A myLogger provides a minimalistic logger satisfying the Logger interface.
@ -43,7 +43,7 @@ func main() {
// consumer
c, err := consumer.New(
*stream,
consumer.WithCheckpoint(ck),
consumer.WithStorage(ck),
consumer.WithLogger(logger),
)
if err != nil {

1
go.mod
View file

@ -7,6 +7,7 @@ require (
github.com/go-sql-driver/mysql v1.4.1
github.com/lib/pq v0.0.0-20180523175426-90697d60dd84
github.com/pkg/errors v0.8.0
github.com/stretchr/testify v1.3.0 // indirect
google.golang.org/appengine v1.6.1 // indirect
gopkg.in/DATA-DOG/go-sqlmock.v1 v1.3.0
gopkg.in/redis.v5 v5.2.9

7
go.sum
View file

@ -2,6 +2,8 @@ github.com/apex/log v1.0.0 h1:5UWeZC54mWVtOGSCjtuvDPgY/o0QxmjQgvYZ27pLVGQ=
github.com/apex/log v1.0.0/go.mod h1:yA770aXIDQrhVOIGurT/pVdfCpSq1GQV/auzMN5fzvY=
github.com/aws/aws-sdk-go v1.15.0 h1:uxi9gcf4jxEX7r8oWYMEkYB4kziKet+1cHPmq52LjC4=
github.com/aws/aws-sdk-go v1.15.0/go.mod h1:mFuSZ37Z9YOHbQEwBWztmVzqXrEkub65tZoCYDt7FT0=
github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/go-ini/ini v1.25.4/go.mod h1:ByCAeIL28uOIIG0E3PJtZPDL8WnHpFKFOtgjp+3Ies8=
github.com/go-ini/ini v1.38.1 h1:hbtfM8emWUVo9GnXSloXYyFbXxZ+tG6sbepSStoe1FY=
github.com/go-ini/ini v1.38.1/go.mod h1:ByCAeIL28uOIIG0E3PJtZPDL8WnHpFKFOtgjp+3Ies8=
@ -14,6 +16,11 @@ github.com/lib/pq v0.0.0-20180523175426-90697d60dd84 h1:it29sI2IM490luSc3RAhp5Wu
github.com/lib/pq v0.0.0-20180523175426-90697d60dd84/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
github.com/pkg/errors v0.8.0 h1:WdK/asTD0HN+q6hsWO3/vpuAkAr+tw6aNJNDFFf0+qw=
github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=

6
options.go
View file

@ -5,10 +5,10 @@ import "github.com/aws/aws-sdk-go/service/kinesis/kinesisiface"
// Option is used to override defaults when creating a new Consumer
type Option func(*Consumer)
// WithCheckpoint overrides the default checkpoint
func WithCheckpoint(checkpoint Checkpoint) Option {
// WithStorage overrides the default storage
func WithStorage(store Store) Option {
return func(c *Consumer) {
c.checkpoint = checkpoint
c.store = store
}
}

13
store.go Normal file
View file

@ -0,0 +1,13 @@
package consumer
// Store interface used to persist scan progress
type Store interface {
GetCheckpoint(streamName, shardID string) (string, error)
SetCheckpoint(streamName, shardID, sequenceNumber string) error
}
// noopStore implements the storage interface with discard
type noopStore struct{}
func (n noopStore) GetCheckpoint(string, string) (string, error) { return "", nil }
func (n noopStore) SetCheckpoint(string, string, string) error { return nil }

8
checkpoint/ddb/ddb.go → store/ddb/ddb.go
View file

@ -87,7 +87,7 @@ type item struct {
// Get determines if a checkpoint for a particular Shard exists.
// Typically used to determine whether we should start processing the shard with
// TRIM_HORIZON or AFTER_SEQUENCE_NUMBER (if checkpoint exists).
func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
func (c *Checkpoint) GetCheckpoint(streamName, shardID string) (string, error) {
namespace := fmt.Sprintf("%s-%s", c.appName, streamName)
params := &dynamodb.GetItemInput{
@ -106,7 +106,7 @@ func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
resp, err := c.client.GetItem(params)
if err != nil {
if c.retryer.ShouldRetry(err) {
return c.Get(streamName, shardID)
return c.GetCheckpoint(streamName, shardID)
}
return "", err
}
@ -116,9 +116,9 @@ func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
return i.SequenceNumber, nil
}
// Set stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// SetCheckpoint stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// Upon failover, record processing is resumed from this point.
func (c *Checkpoint) Set(streamName, shardID, sequenceNumber string) error {
func (c *Checkpoint) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
c.mu.Lock()
defer c.mu.Unlock()

0
checkpoint/ddb/ddb_test.go → store/ddb/ddb_test.go
View file

0
checkpoint/ddb/retryer.go → store/ddb/retryer.go
View file

0
checkpoint/ddb/retryer_test.go → store/ddb/retryer_test.go
View file

8
checkpoint/mysql/mysql.go → store/mysql/mysql.go
View file

@ -77,10 +77,10 @@ func (c *Checkpoint) GetMaxInterval() time.Duration {
return c.maxInterval
}
// Get determines if a checkpoint for a particular Shard exists.
// GetCheckpoint determines if a checkpoint for a particular Shard exists.
// Typically used to determine whether we should start processing the shard with
// TRIM_HORIZON or AFTER_SEQUENCE_NUMBER (if checkpoint exists).
func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
func (c *Checkpoint) GetCheckpoint(streamName, shardID string) (string, error) {
namespace := fmt.Sprintf("%s-%s", c.appName, streamName)
var sequenceNumber string
@ -97,9 +97,9 @@ func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
return sequenceNumber, nil
}
// Set stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// SetCheckpoint stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// Upon failover, record processing is resumed from this point.
func (c *Checkpoint) Set(streamName, shardID, sequenceNumber string) error {
func (c *Checkpoint) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
c.mu.Lock()
defer c.mu.Unlock()

0
checkpoint/mysql/mysql_databaseutils_test.go → store/mysql/mysql_databaseutils_test.go
View file

18
checkpoint/mysql/mysql_test.go → store/mysql/mysql_test.go
View file

@ -72,7 +72,7 @@ func TestNew_WithMaxIntervalOption(t *testing.T) {
ck.Shutdown()
}
func TestCheckpoint_Get(t *testing.T) {
func TestCheckpoint_GetCheckpoint(t *testing.T) {
appName := "streamConsumer"
tableName := "checkpoint"
connString := "user:password@/dbname"
@ -98,7 +98,7 @@ func TestCheckpoint_Get(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnRows(expectedRows)
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != expectedSequenceNumber {
t.Errorf("expected sequence number equals %v, but got %v", expectedSequenceNumber, gotSequenceNumber)
@ -134,7 +134,7 @@ func TestCheckpoint_Get_NoRows(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnError(sql.ErrNoRows)
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != "" {
t.Errorf("expected sequence number equals empty, but got %v", gotSequenceNumber)
@ -170,7 +170,7 @@ func TestCheckpoint_Get_QueryError(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnError(errors.New("an error"))
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != "" {
t.Errorf("expected sequence number equals empty, but got %v", gotSequenceNumber)
@ -184,7 +184,7 @@ func TestCheckpoint_Get_QueryError(t *testing.T) {
ck.Shutdown()
}
func TestCheckpoint_Set(t *testing.T) {
func TestCheckpoint_SetCheckpoint(t *testing.T) {
appName := "streamConsumer"
tableName := "checkpoint"
connString := "user:password@/dbname"
@ -197,7 +197,7 @@ func TestCheckpoint_Set(t *testing.T) {
t.Fatalf("error occurred during the checkpoint creation. cause: %v", err)
}
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Errorf("expected error equals nil, but got %v", err)
@ -218,7 +218,7 @@ func TestCheckpoint_Set_SequenceNumberEmpty(t *testing.T) {
t.Fatalf("error occurred during the checkpoint creation. cause: %v", err)
}
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err == nil {
t.Errorf("expected error equals not nil, but got %v", err)
@ -249,7 +249,7 @@ func TestCheckpoint_Shutdown(t *testing.T) {
result := sqlmock.NewResult(0, 1)
mock.ExpectExec(expectedSQLRegexString).WithArgs(namespace, shardID, expectedSequenceNumber).WillReturnResult(result)
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Fatalf("unable to set checkpoint for data initialization. cause: %v", err)
@ -287,7 +287,7 @@ func TestCheckpoint_Shutdown_SaveError(t *testing.T) {
expectedSQLRegexString := fmt.Sprintf(`REPLACE INTO %s \(namespace, shard_id, sequence_number\) VALUES \(\?, \?, \?\)`, tableName)
mock.ExpectExec(expectedSQLRegexString).WithArgs(namespace, shardID, expectedSequenceNumber).WillReturnError(errors.New("an error"))
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Fatalf("unable to set checkpoint for data initialization. cause: %v", err)

9
checkpoint/postgres/postgres.go → store/postgres/postgres.go
View file

@ -6,6 +6,7 @@ import (
"fmt"
"sync"
"time"
// this is the postgres package so it makes sense to be here
_ "github.com/lib/pq"
)
@ -77,10 +78,10 @@ func (c *Checkpoint) GetMaxInterval() time.Duration {
return c.maxInterval
}
// Get determines if a checkpoint for a particular Shard exists.
// GetCheckpoint determines if a checkpoint for a particular Shard exists.
// Typically used to determine whether we should start processing the shard with
// TRIM_HORIZON or AFTER_SEQUENCE_NUMBER (if checkpoint exists).
func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
func (c *Checkpoint) GetCheckpoint(streamName, shardID string) (string, error) {
namespace := fmt.Sprintf("%s-%s", c.appName, streamName)
var sequenceNumber string
@ -97,9 +98,9 @@ func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
return sequenceNumber, nil
}
// Set stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// SetCheckpoint stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// Upon failover, record processing is resumed from this point.
func (c *Checkpoint) Set(streamName, shardID, sequenceNumber string) error {
func (c *Checkpoint) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
c.mu.Lock()
defer c.mu.Unlock()

0
checkpoint/postgres/postgres_databaseutils_test.go → store/postgres/postgres_databaseutils_test.go
View file

18
checkpoint/postgres/postgres_test.go → store/postgres/postgres_test.go
View file

@ -72,7 +72,7 @@ func TestNew_WithMaxIntervalOption(t *testing.T) {
ck.Shutdown()
}
func TestCheckpoint_Get(t *testing.T) {
func TestCheckpoint_GetCheckpoint(t *testing.T) {
appName := "streamConsumer"
tableName := "checkpoint"
connString := "UserID=root;Password=myPassword;Host=localhost;Port=5432;Database=myDataBase;"
@ -98,7 +98,7 @@ func TestCheckpoint_Get(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnRows(expectedRows)
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != expectedSequenceNumber {
t.Errorf("expected sequence number equals %v, but got %v", expectedSequenceNumber, gotSequenceNumber)
@ -134,7 +134,7 @@ func TestCheckpoint_Get_NoRows(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnError(sql.ErrNoRows)
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != "" {
t.Errorf("expected sequence number equals empty, but got %v", gotSequenceNumber)
@ -170,7 +170,7 @@ func TestCheckpoint_Get_QueryError(t *testing.T) {
tableName)
mock.ExpectQuery(expectedSQLRegexString).WithArgs(namespace, shardID).WillReturnError(errors.New("an error"))
gotSequenceNumber, err := ck.Get(streamName, shardID)
gotSequenceNumber, err := ck.GetCheckpoint(streamName, shardID)
if gotSequenceNumber != "" {
t.Errorf("expected sequence number equals empty, but got %v", gotSequenceNumber)
@ -184,7 +184,7 @@ func TestCheckpoint_Get_QueryError(t *testing.T) {
ck.Shutdown()
}
func TestCheckpoint_Set(t *testing.T) {
func TestCheckpoint_SetCheckpoint(t *testing.T) {
appName := "streamConsumer"
tableName := "checkpoint"
connString := "UserID=root;Password=myPassword;Host=localhost;Port=5432;Database=myDataBase;"
@ -197,7 +197,7 @@ func TestCheckpoint_Set(t *testing.T) {
t.Fatalf("error occurred during the checkpoint creation. cause: %v", err)
}
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Errorf("expected error equals nil, but got %v", err)
@ -218,7 +218,7 @@ func TestCheckpoint_Set_SequenceNumberEmpty(t *testing.T) {
t.Fatalf("error occurred during the checkpoint creation. cause: %v", err)
}
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err == nil {
t.Errorf("expected error equals not nil, but got %v", err)
@ -249,7 +249,7 @@ func TestCheckpoint_Shutdown(t *testing.T) {
result := sqlmock.NewResult(0, 1)
mock.ExpectExec(expectedSQLRegexString).WithArgs(namespace, shardID, expectedSequenceNumber).WillReturnResult(result)
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Fatalf("unable to set checkpoint for data initialization. cause: %v", err)
@ -287,7 +287,7 @@ func TestCheckpoint_Shutdown_SaveError(t *testing.T) {
expectedSQLRegexString := fmt.Sprintf(`INSERT INTO %s \(namespace, shard_id, sequence_number\) VALUES\(\$1, \$2, \$3\) ON CONFLICT \(namespace, shard_id\) DO UPDATE SET sequence_number= \$3;`, tableName)
mock.ExpectExec(expectedSQLRegexString).WithArgs(namespace, shardID, expectedSequenceNumber).WillReturnError(errors.New("an error"))
err = ck.Set(streamName, shardID, expectedSequenceNumber)
err = ck.SetCheckpoint(streamName, shardID, expectedSequenceNumber)
if err != nil {
t.Fatalf("unable to set checkpoint for data initialization. cause: %v", err)

8
checkpoint/redis/redis.go → store/redis/redis.go
View file

@ -36,15 +36,15 @@ type Checkpoint struct {
client *redis.Client
}
// Get fetches the checkpoint for a particular Shard.
func (c *Checkpoint) Get(streamName, shardID string) (string, error) {
// GetCheckpoint fetches the checkpoint for a particular Shard.
func (c *Checkpoint) GetCheckpoint(streamName, shardID string) (string, error) {
val, _ := c.client.Get(c.key(streamName, shardID)).Result()
return val, nil
}
// Set stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// SetCheckpoint stores a checkpoint for a shard (e.g. sequence number of last record processed by application).
// Upon failover, record processing is resumed from this point.
func (c *Checkpoint) Set(streamName, shardID, sequenceNumber string) error {
func (c *Checkpoint) SetCheckpoint(streamName, shardID, sequenceNumber string) error {
if sequenceNumber == "" {
return fmt.Errorf("sequence number should not be empty")
}

6
checkpoint/redis/redis_test.go → store/redis/redis_test.go
View file

@ -12,10 +12,10 @@ func Test_CheckpointLifecycle(t *testing.T) {
}
// set
c.Set("streamName", "shardID", "testSeqNum")
c.SetCheckpoint("streamName", "shardID", "testSeqNum")
// get
val, err := c.Get("streamName", "shardID")
val, err := c.GetCheckpoint("streamName", "shardID")
if err != nil {
t.Fatalf("get checkpoint error: %v", err)
}
@ -30,7 +30,7 @@ func Test_SetEmptySeqNum(t *testing.T) {
t.Fatalf("new checkpoint error: %v", err)
}
err = c.Set("streamName", "shardID", "")
err = c.SetCheckpoint("streamName", "shardID", "")
if err == nil {
t.Fatalf("should not allow empty sequence number")
}