kfk – Kafka for kdb+

Introduction

kfk is a thin wrapper for kdb+ around librdkafka C API for Kafka. It is part of the Fusion for kdb+ interface collection.

This interface is supported for the following platforms

• 32 & 64 bit MacOS and Linux
• 64 bit Windows

New to kdb+ ?

Kdb+ is the world's fastest time-series database, optimized for ingesting, analyzing and storing massive amounts of structured data. To get started with kdb+, please visit https://code.kx.com/q/learn/ for downloads and developer information. For general information, visit https://kx.com/

Documentation

Documentation outlining the functionality available for this interface can be found here.

Running

Linux & Mac

Step 1

Build or install the latest version of librdkafka. The minimum required version is v0.11.0.

Install

macOS

brew install librdkafka

Ubuntu/Debian (unstable)

sudo apt-get install librdkafka-dev

RHEL/CentOS

sudo yum install librdkafka-devel

Build from source

Follow requirements for librdkafka compilation.

To build 32-bit versions on 64-bit OS you need 32-bit versions of libraries and a toolchain.

#CentOS/RHEL
sudo yum install glibc-devel.i686 libgcc.i686 libstdc++.i686 zlib-devel.i686
# Ubuntu
sudo apt-get install gcc-multilib

git clone https://github.com/edenhill/librdkafka.git
cd librdkafka
make clean  # to make sure nothing left from previous build or if upgrading/rebuilding
# If using OpenSSL, remove --disable-ssl from configure command below
# On macOS with OpenSSL you might need to set `export OPENSSL_ROOT_DIR=/usr/local/Cellar/openssl/1.0.2k` before proceeding


# 32 bit
./configure --prefix=$HOME --disable-sasl --disable-lz4 --disable-ssl --mbits=32
# 64 bits
./configure --prefix=$HOME --disable-sasl --disable-lz4 --disable-ssl --mbits=64

make
make install

Step 2

Compile, install and move shared object file to appropriate location.

1. Make sure you have QHOME set as an environment variable.

2. If your librdkafka install is not located in $HOME/include as defaulted by the above instructions set KAFKA_ROOT environment variable to the appropriate include location.

3. Run the following set of commands to set up the system as outlined

// in kfk source folder
make
// move installed `.so` to `$QHOME/<arch>`
make install
// remove `.so` from kfk source folder
make clean

Note: If compiling dynamically linked libkfk.so make sure you have librdkafka.so.1 in your LD_LIBRARY_PATH.

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/lib

Windows

At present the Windows build of the .dll for the kafka interface has been tested on Visual Studio 2017 with librdkafka.redist.1.0.0. The following are the steps completed to achieve this

1. Install nuget for Windows: https:/nuget.com/downloads

2. Install the redistributed version of librdkafka which is suitable for use with windows, documentation can be found here.

    >nuget install librdkafka.redist
   

3. Ensure that you have Windows Visual Studio 2017 installed.

4. Place the installed librdkafka.redist into an appropriate location (suggestions %HOME% or %QHOME%). For the remaining instructions the path to the install is "C:/Users/jdoe/librdkafka.redist.1.0.0"

5. Update LIB user environment variable to include the following path to rdkafka.h for appropriate Windows architecture in this case

    LIB = C:/Users/jdoe/librdkafka.redist.1.0.0/build/native/lib/win/x64/win-x64-Release/v120
   

6. Update PATH system environment variable to include path to native folder for the appropriate computer architecture

    PATH = C:/Users/jdoe/librdkafka.redist.1.0.0/runtimes/win-x64/native
   

7. Create a user environment variable KAFKA_NATIVE in line with the following example path

    KAFKA_NATIVE = C:/Users/jdoe/librdkafka.redist.1.0.0/build/native/include/
   

8. Clone the kafka interface from the KxSystems github

    >git clone https://github.com/kxsystems/kafka
   

9. Move to the kafka/build/ folder within the github clone and run the following;

    >call "build.bat"
   

10. If prompted for input please follow instructions accordingly

11. Move the created .dll from the build folder to %QHOME%/<arch>

Status

This interface is provided here under an Apache 2.0 license.

If you find issues with the interface or have feature requests please consider raising an issue here.

If you wish to contribute to this project please follow the contributing guide here.