Add StringToString transformer

In some cases we'll want to save the data from the stream directly with
no transformation needed. This will allow us to return the raw data
string from the stream

* Add new StringToStringTransformer
* Remove Record from codebase in favor of more generic interface

all_pass_filter.go

@@ -4,6 +4,6 @@ package connector
 type AllPassFilter struct{}
 
 // Returns true for all records.
-func (b *AllPassFilter) KeepRecord(r Record) bool {
+func (b *AllPassFilter) KeepRecord(r interface{}) bool {
 	return true
 }

buffer.go

@@ -6,11 +6,11 @@ package connector
 // time limit in seconds. The ShouldFlush() method may indicate that the buffer is full based on
 // these limits.
 type Buffer interface {
-	ProcessRecord(record Record, sequenceNumber string)
+	ProcessRecord(record interface{}, sequenceNumber string)
 	FirstSequenceNumber() string
 	Flush()
 	LastSequenceNumber() string
 	NumRecordsInBuffer() int
-	Records() []Record
+	Records() []interface{}
 	ShouldFlush() bool
 }

filter.go

@@ -6,5 +6,5 @@ package connector
 // A method enabling the buffer to filter records. Return false if you don't want to hold on to
 // the record.
 type Filter interface {
-	KeepRecord(r Record) bool
+	KeepRecord(r interface{}) bool
 }

record.go

@@ -1,7 +0,0 @@
-package connector
-
-// Used to store the data being sent through the Kinesis stream
-type Record interface {
-	ToDelimitedString() string
-	ToJson() []byte
-}

record_buffer.go

@@ -4,16 +4,16 @@ package connector
 // records that are periodically flushed. It is configured with an implementation of Filter that
 // decides whether a record will be added to the buffer to be emitted.
 type RecordBuffer struct {
-	NumRecordsToBuffer  int
+	NumRecordsToBuffer int
 
 	firstSequenceNumber string
 	lastSequenceNumber  string
-	recordsInBuffer     []Record
+	recordsInBuffer     []interface{}
 	sequencesInBuffer   []string
 }
 
 // Adds a message to the buffer.
-func (b *RecordBuffer) ProcessRecord(record Record, sequenceNumber string) {
+func (b *RecordBuffer) ProcessRecord(record interface{}, sequenceNumber string) {
 	if len(b.sequencesInBuffer) == 0 {
 		b.firstSequenceNumber = sequenceNumber
 	}
@@ -27,7 +27,7 @@ func (b *RecordBuffer) ProcessRecord(record Record, sequenceNumber string) {
 }
 
 // Returns the records in the buffer.
-func (b *RecordBuffer) Records() []Record {
+func (b *RecordBuffer) Records() []interface{} {
 	return b.recordsInBuffer
 }
 

string_to_string_transformer.go

@@ -0,0 +1,11 @@
+package connector
+
+type StringToStringTransformer struct{}
+
+func (t StringToStringTransformer) ToRecord(data []byte) interface{} {
+	return string(data)
+}
+
+func (t StringToStringTransformer) FromRecord(s interface{}) []byte {
+	return []byte(s.(string))
+}

transformer.go

@@ -3,6 +3,6 @@ package connector
 // Transformer is used to transform data (byte array) to a Record for
 // processing in the application.
 type Transformer interface {
-	ToRecord(data []byte) Record
+	ToRecord(data []byte) interface{}
-	FromRecord(r Record) []byte
+	FromRecord(r interface{}) []byte
 }