wip

codec/closer.go

@@ -6,6 +6,6 @@ type Closer interface {
 
 type nullCloser struct{}
 
-func (n *nullCloser) Close() error {}
+func (n *nullCloser) Close() error { return nil }
 
 var NoopCloser = new(nullCloser)

context.go

@@ -170,6 +170,8 @@ type cbContext struct {
 	// tracking statistics for the output topic
 	trackOutputStats func(ctx context.Context, topic string, size int)
 
+	deferreds []func()
+
 	msg      *message
 	done     bool
 	counters struct {
@@ -345,10 +347,13 @@ func (ctx *cbContext) valueForKey(key string) (interface{}, error) {
 		return nil, fmt.Errorf("Cannot access state in stateless processor")
 	}
 
-	data, err := ctx.table.Get(key)
+	data, closer, err := ctx.table.Get(key)
 	if err != nil {
 		return nil, fmt.Errorf("error reading value: %v", err)
-	} else if data == nil {
+	}
+	ctx.deferreds = append(ctx.deferreds, func() { _ = closer.Close() })
+
+	if data == nil {
 		return nil, nil
 	}
 
@@ -450,6 +455,12 @@ func (ctx *cbContext) tryCommit(err error) {
 	if ctx.errors.ErrorOrNil() != nil {
 		ctx.asyncFailer(fmt.Errorf("could not commit message with key '%s': %w", ctx.Key(), ctx.errors.ErrorOrNil()))
 	} else {
+
+		// execute deferred commit functions in reverse order
+		for i := len(ctx.deferreds) - 1; i >= 0; i-- {
+			ctx.deferreds[i]()
+		}
+
 		ctx.commit()
 	}
 

examples/2-clicks/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"time"
@@ -58,7 +59,7 @@ func (jc *userCodec) Decode(data []byte) (interface{}, error) {
 	return &c, nil
 }
 
-func (jc *userCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (jc *userCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := jc.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/3-messaging/blocker/blocker.go

@@ -3,6 +3,7 @@ package blocker
 import (
 	"context"
 	"encoding/json"
+	"io"
 
 	"github.com/lovoo/goka"
 	"github.com/lovoo/goka/codec"
@@ -30,7 +31,7 @@ func (c *BlockEventCodec) Decode(data []byte) (interface{}, error) {
 	return &m, json.Unmarshal(data, &m)
 }
 
-func (c *BlockEventCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *BlockEventCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }
@@ -49,7 +50,7 @@ func (c *BlockValueCodec) Decode(data []byte) (interface{}, error) {
 	return &m, json.Unmarshal(data, &m)
 }
 
-func (c *BlockValueCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *BlockValueCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/3-messaging/collector/collector.go

@@ -3,6 +3,7 @@ package collector
 import (
 	"context"
 	"encoding/json"
+	"io"
 
 	"github.com/lovoo/goka"
 	"github.com/lovoo/goka/codec"
@@ -29,7 +30,7 @@ func (c *MessageListCodec) Decode(data []byte) (interface{}, error) {
 	return m, err
 }
 
-func (c *MessageListCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *MessageListCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/3-messaging/detector/detector.go

@@ -3,6 +3,7 @@ package detector
 import (
 	"context"
 	"encoding/json"
+	"io"
 
 	"github.com/lovoo/goka"
 	"github.com/lovoo/goka/codec"
@@ -34,7 +35,7 @@ func (c *CountersCodec) Decode(data []byte) (interface{}, error) {
 	return &m, json.Unmarshal(data, &m)
 }
 
-func (c *CountersCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *CountersCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/3-messaging/message.go

@@ -2,6 +2,7 @@ package messaging
 
 import (
 	"encoding/json"
+	"io"
 
 	"github.com/lovoo/goka"
 	"github.com/lovoo/goka/codec"
@@ -29,7 +30,7 @@ func (c *MessageCodec) Decode(data []byte) (interface{}, error) {
 	return &m, json.Unmarshal(data, &m)
 }
 
-func (c *MessageCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *MessageCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }
@@ -46,7 +47,7 @@ func (c *MessageListCodec) Decode(data []byte) (interface{}, error) {
 	return m, err
 }
 
-func (c *MessageListCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *MessageListCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/5-multiple/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"net/http/pprof"
@@ -67,7 +68,7 @@ func (jc *userCodec) Decode(data []byte) (interface{}, error) {
 	return &c, nil
 }
 
-func (jc *userCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (jc *userCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := jc.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/7-redis/codec.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"encoding/json"
+	"io"
 
 	"github.com/lovoo/goka/codec"
 )
@@ -21,7 +22,7 @@ func (c *Codec) Decode(data []byte) (interface{}, error) {
 	return event, err
 }
 
-func (c *Codec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (c *Codec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := c.Decode(data)
 	return dec, codec.NoopCloser, err
 }

examples/8-monitoring/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"net/http/pprof"
@@ -63,7 +64,7 @@ func (jc *userCodec) Decode(data []byte) (interface{}, error) {
 	return &c, nil
 }
 
-func (jc *userCodec) DecodeP(data []byte) (interface{}, io.closer, error) {
+func (jc *userCodec) DecodeP(data []byte) (interface{}, io.Closer, error) {
 	dec, err := jc.Decode(data)
 	return dec, codec.NoopCloser, err
 }