Using the kdb Insights Python interface

The Python interface allows you to publish data to RT in your own Python application.

This section details how to get started with the Python interface.

Downloading the Python interface

You can download the Python interface from the kdb Insights Nexus registry.

Supported Operating Systems

The Python interface is supported on the following operating systems:

• CentOS 8 or later

• Red Hat Enterprise Linux (RHEL) 8 or later

• Ubuntu 18.04 or later

• Windows

Prerequisites

The Python interface requires the following system packages:

• libssl

• libcurl

Installation

Install the Python interface via pip.

1. Ensure you have the latest version of pip:

   pip install --upgrade pip
   

2. Install the package:

   pip install --extra-index-url https://nexus.dl.kx.com/repository/kxi-pypi-public/simple/ kxi-rtpy
   

   The interface uses PyKX

   The pip install command will also install PyKX if it is not already present.

Using the Python interface in your own application

To publish data to kdb Insights Enterprise using the Python interface as part of your own application, use the rtpy module. This module contains the functionality to connect to kdb Insights Enterprise and publish the data into the system.

Initializing

1. Start the Python interpreter and import the rtpy module:

   from rtpy import Publisher, RTParams
   

2. Create an RTParams configuration object. Sample params objects below:

   params = RTParams(config_url='file:///tmp/rt_config.json', rt_dir='/tmp/tmprt')
   params = RTParams(prefix='my-', stream='data' client_name='mypublisher', rt_dir='/tmp/tmprt') ## This would send data to the RT stream 'my-data'
   

   See the Parameters section for the full list of configuration parameters.

   config_url

   The config_url can be either a kdb Insights Enterprise client URL or the path to a local JSON file (using the file URI scheme) containing the RT configuration. See the getting started guide for more details.

Parameters

The RTParams class contains the following RT connection configuration parameters.

parameter	required	description
rt_dir	Yes	RT directory
config_url	No	The URL/file that is called/read to get the RT endpoint(s)
prefix	No	The RT stream prefix you want to send data to
stream	No	The RT stream name you want to send data to
client_name	No	The client name that the user can assign to their publisher. Useful when running multiple publishers from a single node/server
query_timeout	No	Milliseconds to wait for the connection to be established
fetch_config_sleep	No	Time in ms to sleep between reads of the configuration details
config_max_age	No	Maximum age of configuration in milliseconds
local_persistence_period	No	Local persistence period in milliseconds
log_level	No	Log level: info, warn, err, or off
console_log_level	No	Console log level: info, warn, err, or off
ca_info_file	No	Path to Certificate Authority certificate bundle
dedup_id	No	ID to dedup multiple publishers

See the C interface documentation for the list of default values.

Publishing data

The Publisher class implements the Python context manager protocol. The functions to connect and disconnect from RT are called implicitly when entering and exiting the with block below.

1. Create some data and publish it to RT:

   from rtpy import Publisher, RTParams
   import pykx as kx
   from datetime import *
   import uuid
   params = RTParams(config_url='file:///tmp/client.json', rt_dir='/tmp/tmprt')
   with Publisher(params) as pub:
   now = datetime.utcnow()
   trade_id = uuid.uuid4()
   # Send a Python list
   data = ["hello", 1234, 3.14, now]
   pub("test", data)
   # A kdb+ license is required to use the PyKX Table object
   data = kx.Table([[now, "VOD", "LSE", "buy", 75.90, 100, trade_id]], columns=['time','sym','exch','side','price','size','tradeID'])
   pub("trade", data)
   

Next Steps

Learn how to use our sample Python program. to publish data.