OnixS C++ CME MDP Streamlined Market Data Handler  1.2.0
API Documentation
Getting Started

Inner Contents

 Adjusting Handler Settings
 
 Setting Up Feed Engine
 
 Handling Issues Like Errors and Warnings
 
 Market Data Processing Session
 
 Listening to Market Data
 
 Using TCP Recovery Facility
 
 Logging Services
 
 Replaying Log Files
 

Detailed Description

The OnixS::CME::Streamlined::MDH namespace encapsulates the SDK API. The master OnixS/CME/Streamlined/MDH.h header file collects all header files for more convenience.

Following sections guide through the major steps to be done to succeed with market data processing.

Initializing and Licensing SDK

The SDK needs a valid license for successful execution. If the licensing subsystem is not able to find a valid license, it throws an exception at the initialization stage when the OnixS::CME::Streamlined::MDH::initialize is called. Also, a license is verified each time an attempt to start market data processing is done using the OnixS::CME::Streamlined::MDH::Handler::start member.

The OnixS::CME::Streamlined::MDH::InitializationSettings class exposes the OnixS::CME::Streamlined::MDH::InitializationSettings::licenseStore member which must be used to instruct the SDK where to look for a valid license. By default, the licensing services look for a license in the current directory of the application. However, by using noted parameter, it is possible to specify another folder anywhere on file system.

Note
The licensing subsystem looks for a valid license in the specified folder and selects the best one. If multiple licenses are available, it selects the most significant one (for example, a production license is selected instead of a trial one if both are available).

The following example demonstrates how to perform one-time SDK initialization:

// Parameters for one-time initialization.
InitializationSettings settings;
// The folder in which the license is stored.
settings.licenseStore("license");
// Initializes all Handler services explicitly.

Configuring and Constructing the Handler

The OnixS::CME::Streamlined::MDH::Handler class incapsulates a market data processing machinery. A single instance of the OnixS::CME::Streamlined::MDH::Handler processes market data for a single CME channel.

The users must define settings affecting market data processing behavior before constructing an instance of the OnixS::CME::Streamlined::MDH::Handler class.

The OnixS::CME::Streamlined::MDH::HandlerSettings class contains all parameters controlling various aspects of market data processing including the behavior of the OnixS::CME::Streamlined::MDH::Handler.

In the most cases, default values are set for parameters defining the most likely behavior of the OnixS::CME::Streamlined::MDH::Handler instance. However, some parameters must be set explicitly before constructing an instance of the OnixS::CME::Streamlined::MDH::Handler class.

HandlerSettings settings;
settings.channel(310);
settings.
feeds().
connectivityConfigurationFile("config.xml");
Handler handler(settings);

See Handler's Settings for more information on adjusting behavior of the Handler.

Binding Feed Engine to the Handler

The OnixS::CME::Streamlined::MDH::FeedEngine class encapsulates a layer responsible for receiving market data which is transmitted by the CME. Therefore, to have successful processing of market data, it is necessary to construct an instance of the Feed Engine and to bind it to the previously constructed instance of the OnixS::CME::Streamlined::MDH::Handler class:

FeedEngineSettings feSettings;
FeedEngine feedEngine(feSettings);
handler.bindFeedEngine(feedEngine);

See Feed Engine for more details on Feed Engine.

Note
An instance of the OnixS::CME::Streamlined::MDH::Handler does not manage lifetime of a bound OnixS::CME::Streamlined::MDH::FeedEngine instance. Therefore, user responsibility is to keep an instance of the OnixS::CME::Streamlined::MDH::FeedEngine class valid while it is bound to an instance of OnixS::CME::Streamlined::MDH::Handler class.

Logging Market Data and Other Events (Optional)

The Handler may log market data it processes for further use by replay feature or analysis as well as other important events which may take place during regular market data processing.

The OnixS::CME::Streamlined::MDH::Logger abstract class encapsulates the logging subsystem. The SDK provides various implementations of logging for different purposes. File-based logging is satisfactory choise for the most cases.

Below is an example of how file based logging can be established:

FileLoggerSettings loggerSettings;
// Sets filename of log as it was used by older Handlers.
loggerSettings.filename(makeLogFilename(310));
// Varies which events are to be logged.
loggerSettings.severityLevel(LogSeverity::Debug);
FileLogger logger(loggerSettings);
handler.bindLogger(logger);
Note
An instance of the OnixS::CME::Streamlined::MDH::Handler does not manage lifetime of a bound OnixS::CME::Streamlined::MDH::Logger instance. Therefore, user responsibility is to keep an instance of the OnixS::CME::Streamlined::MDH::Logger class valid while it is bound to an instance of OnixS::CME::Streamlined::MDH::Handler class.

Subscribing to Market Data Events

Once an instance of the OnixS::CME::Streamlined::MDH::Handler is constructed and bound to an instance of the OnixS::CME::Streamlined::MDH::FeedEngine, market data processing can be started. However, it's necessary to subscribe to corresponding events to get the results of market data processing like updated order books.

See the Event Listeners topic concerning which events are exposed by the Handler and how to subscribe to a particular event.

Spawning Market Data Processing

As soon as an instance of the OnixS::CME::Streamlined::MDH::Handler is configured, bound to a valid instance of the OnixS::CME::Streamlined::MDH::FeedEngine and listeners for events are registered, market data processing can be initiated.

Market data processing is initiated by invoking the OnixS::CME::Streamlined::MDH::Handler::start member, which accepts an instance of OnixS::CME::Streamlined::MDH::SessionSettings class defining the behavior of the Handler for the session.

For the most common processing scenarios, the SDK exposes ready-to-use presets of session settings: OnixS::CME::Streamlined::MDH::AccurateLateJoinSession(), OnixS::CME::Streamlined::MDH::AccuratePreopeningSession, OnixS::CME::Streamlined::MDH::NaturalRefreshSession, etc. See documentation for noted classes for more details.

handler.start(AccurateLateJoinSession());

The OnixS::CME::Streamlined::MDH::Handler::stop member must be called to accomplish live market data processing:

handler.stop();
Note
For more and up-to-date information on getting started aspects, see GettingStarted sample from the samples collection available in distributive package.