A Golang client library for AWS Kinesis.
The Golang KCL supports everything needed to write Kinesis stream consumers. It offers the same functionality as the official Python KCL:
This is an unofficial KCL created outside of AWS.
The Golang KCL has been tested for basic functionality. It can consume records, checkpoint, and handle shard creation and merges.
Feedback and bug reports can be submitted through Github Issues and are greatly appreciated.
To build the example:
cd gokinesis export GOPATH=`pwd` cd examples/trivial go build .
See examples/trivial/README.md for instructions on how to invoke the KCL MultiLangDaemon on the trivial consumer demo.
To write a consumer, implement a struct satisfying the kinesis.RecordConsumer interface.
Init(shardId string)is called at start.
ProcessRecords(batch *KclRecord, cp *Checkpointer)is invoked for each batch of messages to be processed.
Shutdown(t ShutdownType, cp *Checkpointer)is called at finish. No further calls to the RecordConsumer are made after this. Implementations must check the ShutdownType. Invoke a checkpoint if it's graceful; do NOT checkpoint if it's ZOMBIE.
If the implementation returns an non-nil error on any of these three methods, the Golang KCL will exit immediately with a non-zero exit code.
In the Checkpointer, CheckpointAll() marks to the end of the most recently delivered batch of records. CheckpointSeq() marks to a specific sequence number. Checkpointing returns a non-nil error on conditions which can be retried.
To begin processing, instantiate the struct and pass it to kinesis.Run().
An example of this is shown in examples/trivial/trivial.go
Note: there should be only a single RecordProcessor and invocation of kinesis.Run(). The MultiLangDaemon protocol uses stdin/stdout to communicate and does not support multiple consumers in one process. Instead, it spawns multiple independent processes which are each assigned a single shard.
Note: the KCL MultiLangDaemon uses stdin and stdout to communicate with the client. Any consumer output should go elsewhere (e.g. stderr or a file).
The KCL MultiLangDaemon protocol restricts when checkpointing may happen. Accordingly, an interface and controller function rather than a Go channel is used for processing records.
The MIT License (MIT)
Copyright (c) 2014-2015 Niek J. Sanders
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.