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Bloomberg Open API – Publishing Developer Guide
BLOOMBERG L.P.
OPEN API
PUBLISHING DEVELOPER
GUIDE
Version: 1.2
Last Updated: 07/31/2015
©2015 BLOOMBERG L.P. ALL RIGHTS RESERVED
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Bloomberg Open API – Publishing Developer Guide
Related Documents
Document Name
Core User Guide
Core Developer Guide
Enterprise User Guide
Enterprise Developer Guide
Publishing User Guide
Reference Guide - Bloomberg Services and Schemas
Reference Symbology Guide
All materials including all software, equipment and documentation made available by Bloomberg are for informational purposes only.
Bloomberg and its affiliates make no guarantee as to the adequacy, correctness or completeness of, and do not make any
representation or warranty (whether express or implied) or accept any liability with respect to, these materials. No right, title or interest is
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Bloomberg Open API – Publishing Developer Guide
Contents
1.
About This Guide...................................................................................................................................... 4
2.
Publishing Overview ................................................................................................................................ 4
Simple Broadcast ................................................................................................................................. 4
2.1.
2.1.1
Creating a Session........................................................................................................................... 5
2.1.2
Obtaining Authorization ................................................................................................................... 5
2.1.3
Creating the Topic ............................................................................................................................ 7
2.1.4
Publishing Events............................................................................................................................. 7
Interactive Publisher ............................................................................................................................ 8
2.2.
2.2.1.
Registration ....................................................................................................................................... 9
2.2.2.
Event Handling ................................................................................................................................. 9
2.2.3.
Publication ....................................................................................................................................... 11
3.
Publishing Classes................................................................................................................................. 12
ProviderSession ................................................................................................................................. 12
3.1.
3.1.1.
Session Options/Software Failover ............................................................................................. 13
Services ............................................................................................................................................... 13
3.2.
3.2.1.
Registering a Service .................................................................................................................... 13
3.3.
Topics and TopicList .......................................................................................................................... 14
3.4.
Events and EventFormatter .............................................................................................................. 14
3.4.1.
Example Event Structure .............................................................................................................. 15
3.4.2.
Event Formatter .............................................................................................................................. 15
4.
Local Publishing ..................................................................................................................................... 16
4.1.
Publisher Groups................................................................................................................................ 17
4.2.
Launchpad Page Publishing ............................................................................................................. 17
5.
Platform Failover .................................................................................................................................... 19
6.
Contribution ............................................................................................................................................. 20
6.1.
Contribution Example Code.............................................................................................................. 20
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Bloomberg Open API – Publishing Developer Guide
1. About This Guide
The Publishing Developer’s Guide is designed to help understand the concept of Publishing and how
Bloomberg L.P. API allows customer applications to publish data as well as consume it. Customer data can
be published for distribution within the customer’s enterprise, contributed to the Bloomberg infrastructure,
distributed to others, or used for warehousing.
2. Publishing Overview
The Bloomberg API allows customer applications to publish data as well as consume it. Customer data can
be published for distribution within the customer’s enterprise, contributed to the Bloomberg infrastructure,
distributed to others, or used for warehousing.
Connect
Authorize
Register Service
Receive Events
Subscription Requests
Recap Requests
Unsubscribe Requests
Start processing for topic
Resend current image for topic
Stop any processing for topic
Asynchronously publish updates
Figure 1: Publishing Flow
Publishing applications might simply “broadcast” data or they can be “interactive”, responding to feedback
from the infrastructure about the currently active subscriptions from data consumers. This will illustrate
both paradigms. There are two Programming Examples:
BroadcastOneTopic.cpp
InteractivePublisher.cpp.
2.1.
Simple Broadcast
In a simple broadcast, the publishing application sends data but has no indication if anyone is consuming
that data. In this simple example, data will be produced for a single topic. The major stages are:
Creating a session
Obtaining authorization
Creating the topic
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Bloomberg Open API – Publishing Developer Guide
Publishing events for the topic to the designated service
2.1.1 Creating a Session
Sessions for publication are created in the same manner as those for consuming data. The key difference is
that they are managed by an instance of ProviderSession instead of Session.
The event handler plays no significant role in this example and will NOT be examined.
// BroadcastOneTopic.cpp
… …
int main()
{
SessionOptions sessionOptions;
sessionOptions.setServerHost("platform");
sessionOptions.setServerPort(8197);
sessionOptions.setAuthenticationOptions("AuthenticationType=OS_LOGON")
; MyEventHandler myEventHandler;
ProviderSession session(sessionOptions, &myEventHandler, 0);
if (!session.start()) {
std::cerr <<"Failed to start session." << std::endl; return 1;
}… …
}
2.1.2 Obtaining Authorization
The authorization stage, if successful, provides a valid Identity object which is required for later operations.
Authorization is done by the "//blp/apiauth" service on receipt of an authorization request.
For additional information on “Authorization and Permissioning Systems” refer to the Enterprise User
Guide.
Name TOKEN("token");
Name TOKEN_SUCCESS("TokenGenerationSuccess"); Name
TOKEN_FAILURE("TokenGenerationFailure");
Name AUTHORIZATION_SUCCESS("AuthorizationSuccess");
EventQueue tokenEventQueue;
session.generateToken(CorrelationId(), &tokenEventQueue);
std::string token;
Event event = tokenEventQueue.nextEvent();
if (event.eventType() == Event::TOKEN_STATUS) {
MessageIterator iter(event);
while (iter.next()) {
Message msg = iter.message();
msg.print(std::cout);
if (msg.messageType() == TOKEN_SUCCESS) {
token = msg.getElementAsString(TOKEN);
}
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Bloomberg Open API – Publishing Developer Guide
else if (msg.messageType() == TOKEN_FAILURE) {
break;
}
}
}
if (token.length() == 0) {
std::cout << "Failed to get token" << std::endl;
}
session.openService("//blp/apiauth");
Service authService = session.getService("//blp/apiauth");
Request authRequest =
authService.createAuthorizationRequest();
authRequest.set(TOKEN, token.c_str());
EventQueue authQueue;
Identity providerIdentity = session.createIdentity();
session.sendAuthorizationRequest(
authRequest, &providerIdentity, CorrelationId(), &authQueue);
else if (event.eventType() == EventType.RESPONSE
|| event.eventType() == EventType.PARTIAL_RESPONSE
|| event.eventType() == EventType.REQUEST_STATUS)
{ for (Message msg: event) {
if
(msg.correlationID().equals(d_authorizationResponseCorrelationId
)) { Object authorizationResponseMonitor =
msg.correlationID().obje
ct(); synchronized (authorizationResponseMonitor) {
if (msg.messageType() == AUTHORIZATION_SUCCESS) {
d_authorizationResponse = Boolean.TRUE;
authorizationResponseMonitor.notifyAll();
}
else if (msg.messageType() == AUTHORIZATION_FAILURE) {
d_authorizationResponse = Boolean.FALSE;
System.err.println("Not authorized: " +
msg.getElement("reason"));
}
else {
assert d_authorizationResponse == Boolean.TRUE;
System.out.println("Permissions updated");
}
}
}
}
}
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Bloomberg Open API – Publishing Developer Guide
2.1.3 Creating the Topic
Before publishing data, the application must create a Topic object on the appropriate service. This example
uses synchronous method createTopics() of the ProviderSession to create a Topic on //blp/test
service from a topic string "testtopic".
… …
const std::string myService = "//blp/test";
const std::string
myTopic
= "testtopic";
TopicList topicList;
topicList.add((myService + "/ticker/" + myTopic).c_str(),
CorrelationId((long long)1));
session.createTopics(
&topicList,
ProviderSession::AUTO_REGISTER_SERVICES,
providerIdentity);
Topic topic;
for (size_t i = 0; i < topicList.size(); ++i) {
if (topicList.statusAt(i) == TopicList::CREATED) {
topic = session.getTopic(topicList.messageAt(i));
}
}
… …
2.1.4 Publishing Events
In this example, data is published by sending events to the designated service, "//blp/test". Event
objects are obtained from the service and populated with the topic and the application specific data. In this
simple example, each event contains a single data message; however, in general, each event can contain
multiple messages. In this simple example, the data is just an integer value that is incremented and
published every ten seconds.
… …
Name messageType ("MyMessageType");
Name fieldType ("MyFieldType");
Service service = session.getService(myService.c_str());
for (int value = 1; true; ++value, sleep(10)) {
Event event = service.createPublishEvent();
EventFormatter eventFormatter(event);
eventFormatter.appendMessage(messageType, topic);
eventFormatter.setElement(fieldName, value);
session.publish(event);
}
session.stop();
return 0;
}
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Bloomberg Open API – Publishing Developer Guide
Note: The standard C library 'sleep' function is used above. The argument specifies the number of
seconds to sleep.
2.2.
Interactive Publisher
The Bloomberg infrastructure can send events to provider applications when data is needed for a given
topic. These events allow the customer applications to "interact" with the Bloomberg infrastructure. Data
for a topic need be published only when it is known to have subscribers.
In this simple example, data is published, only as needed, for a set of topics on a single service. The major
steps involved are:
Creating a session
Obtaining authorization
Registering for subscription start and stop messages
Handling subscription start/stop events, which add and remove topics to the active publication set
Creating a topic
Publishing events for the active topics of the designated service
The details for creating a session, obtaining a provider identity, and authorization are the same as for
‘Simple Broadcast’; they will not be detailed again.
This design requires the management of a collection of "active" topics for publication. That collection will be
populated (and depopulated) by event handling threads and accessed for periodic publication by the main
thread. A map will be used to store pairs of topic/CUSIP pairs (keyed on topic). The topics are provided in
the start and stop messages, and CUSIPs are obtained by requesting resolution of the received topics.
The multiple threads of this application must not concurrently access the collection; standard template
library (STL) containers are not thread-safe in that respect. Since there is only one "reading" thread in this
application, a simple mutex suffices. A pthread mutex was chosen because it is familiar to many readers.
The event handler is designed to hold pointers to the collection of active topics and to the mutex that
manages access to that collection.
// InteractivePublisher.cpp
… …
int main(int argc, char **argv)
{
Publications activePublications; pthread_mutex_t
activePublicationsMutex;
pthread_mutex_init(&activePublicationsMutex, NULL); MyEventHandler
myEventHandler(&activePublications,
&activePublicationsMutex);
SessionOptions sessionOptions;
sessionOptions.setServerHost("192.168.9.155");
sessionOptions.setServerPort(8197);
//sessionOptions.setAuthenticationOptions("AuthenticationType=OS_LOGON");
sessionOptions.setAuthenticationOptions("AuthenticationMode=APPLICATION_ONLY;
ApplicationAuthenticationType=APPNAME_AND_KEY;ApplicationName=blp:APP_BBOX");
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Bloomberg Open API – Publishing Developer Guide
ProviderSession session(sessionOptions, &myEventHandler, 0);
if (!session.start()) {
std::cerr << "Failed to start session." << std::endl;
return -1;
}
2.2.1. Registration
On completion of service registration, the application can expect subscription start and subscription stop
messages in the context of subscription status events.
… … create ’activePublication’ collection, the managing mutex,
and the event handler … …
… … create ’session’ and obtain ’Identity’… …
const char *myService = "//blp/mktdata8";
if (!session.registerService(myService, providerIdentity)) {
std::cerr <<"Failed to register " << myService << std::endl;
return -1;
}
… …
}
2.2.2. Event Handling
The event handler in this example is detailed below. The relevant event type is TOPIC_STATUS. The
TOPIC_STATUS event has three message types of interest: TOPIC_CREATED, TOPIC_SUBSCRIBED,
and TOPIC_UNSUBSCRIBED.
On receipt of "started" type messages, the event handler adds the topic to a set of topics that require
asynchronous topic creation. Once all of the messages in the event have been examined, that list (if nonempty) is sent for resolution. Use of the session’s createTopicsAsync method means that the
operation does not block. Rather, the result is returned in a separate event of type TOPIC_CREATED.
When messages indicating successful topic creation are received, the event handler extracts the topic and
the corresponding string, creates an item, and adds that item to the collection of active publications. Since
a topic may have received a "stop" message while it was being created, there is first a check to see if the
topic is still in the "needed" set before it is added to the "active" collection.
On receipt of a "stopped" type, the event handler extracts the topic from the message and deletes the
corresponding item in the collection of active publications or the collection of topics needing creation.
Note that all operations use the provided mutex to provide exclusive access for each other.
bool MyEventHandler::processEvent(const Event& event, ProviderSession*
session)
{
switch (event.eventType()) {
case Event::TOPIC_STATUS: {
TopicList topicList;
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Bloomberg Open API – Publishing Developer Guide
MessageIterator iter(event);
while (iter.next()) {
Message msg = iter.message();
std::cout << msg << std::endl;
if (msg.messageType() == TOPIC_SUBSCRIBED)
{ Topic topic;
try {
topic = session->getTopic(msg);
}
catch (blpapi::Exception &) {
}
if (!topic.isValid()) {
topicList.add(msg);
}
else if (d_actPub_p->find(topic) == d_actPub_p->end())
{ std::string topicStr =
msg.getElementAsString("topic");
pthread_mutex_lock(d_actMutex_p);
PublicationItem publicationItem(topic, topicStr);
d_actPub_p->insert(publicationItem);
pthread_mutex_unlock(d_actMutex_p);
}
}
else if (msg.messageType() == TOPIC_UNSUBSCRIBED) {
Topic topic;
try {
topic = session->getTopic(msg);
pthread_mutex_lock(d_actMutex_p);
Publications::iterator it = d_actPub_p->find(topic);
if (it != d_actPub_p->end()) {
d_actPub_p->erase(it);
}
pthread_mutex_unlock(d_actMutex_p);
}
catch (blpapi::Exception &) {
}
}
else if (msg.messageType() == TOPIC_CREATED) {
try {
Topic topic = session->getTopic(msg);
std::string topicStr =
msg.getElementAsString("topic");
pthread_mutex_lock(d_actMutex_p);
PublicationItem publicationItem(topic, topicStr);
d_actPub_p->insert(publicationItem);
pthread_mutex_unlock(d_actMutex_p);
} catch (blpapi::Exception &e) {
std::cerr
<< "Exception in Session::getTopic(): "
<< e.description()
<< std::endl;
continue;
}
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Bloomberg Open API – Publishing Developer Guide
}
}
if (topicList.size()) {
session->createTopicsAsync(topicList);
}
}
break
;
defau
lt:
printMessages(event);
}
return true;
}
2.2.3. Publication
The publication loop in this example is, in many ways, similar to that used in the first example. There is a
value that is incremented every ten seconds and is used to create an event for publication.
Service service = session.getService(myService);
Name messageType("MyMessageType");
Name fieldName("MyFieldName");
for (int value = 1; true; ++ value, sleep(10)) {
pthread_mutex_lock(&activePublicationsMutex);
if (0 == activePublications.size()) {
continue;
}
Event event = service.createPublishEvent(); EventFormatter
eventFormatter(event);
for (Publications::iterator iter = activePublications.begin();
iter != activePublications.end();
++iter) {
const std::string& cusip = iter->second;
eventFormatter.appendMessage(messageType, iter->first);
eventFormatter.setElement(fieldName, myValueFor(cusip,
value));
}
pthread_mutex_unlock(&activePublicationsMutex);
session.publish(event);
}
session.stop();
return 0;
}
Note: The standard C library 'sleep' function is used above. The argument specifies the number
of seconds to sleep.
However, there are some differences, rather than a single fixed topic, publication is made for all of the
topics in the collection of active publications.
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Bloomberg Open API – Publishing Developer Guide
Note that the mutex is acquired before iterating over that collection.
There is at most one published event per cycle. Each event may have multiple messages, each with data
for a specific topic. Although sending an empty event would not be harmful, if the collection of active
publications is empty, no event is published for that cycle. The published data might vary by topic.
Details of the myValueFor function are not important and, therefore, not shown.
3. Publishing Classes
This section gives an overview on the Publishing classes for the Platform. The figure below displays the
Class Representations in detail, each one of these will be explained in detail.
Concepts
Classes
ProviderSession
Platform
Schemas
Services
Resolve
Service
Topic
Messages
Data
DaData
Figure 2: Platform Class Datata
Representation
3.1.
Service
Topic
String
Events
Session
Options
Event
Formatter
TopicList
Event
Element
Element
ProviderSession
The ProviderSession object provides the context of a customer application's connection to the
Bloomberg infrastructure via the Bloomberg API. Having a ProviderSession object, customer applications
can use them to create Service objects for using specific Bloomberg services.
The SessionOptions class is used to initiate ProviderSession:
SessionOptions sessionOptions;
ProviderSession session(sessionOptions,
&myEventHandler, 0);
if (!session.start())
{
HandleFailure();
return;
}
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Bloomberg Open API – Publishing Developer Guide
3.1.1. Session Options/Software Failover
The SessionOptions class provides all of the initialization information that the ProviderSession requires.
Many of its methods are used to implement a software failover mechanism. Given a list of possible hosts
(d_hosts) and a port to connect on (d_port), the SessionOptions class can be populated with a number
of potential hosts to connect to.
for (size_t i = 0; i < d_hosts.size(); ++i)
{
sessionOptions.setServerAddress(d_hosts[i],
d_port, i);
}
The options to enable the failover are as follows:
sessionOptions.setAutoRestartOnDisconnection(true);
sessionOptions.setNumStartAttempts(d_hosts.size());
Once the API receives a disconnection event, or tries to connect to a server that isn’t active, it will
advance to the next host on the list.
3.2.
Services
All Bloomberg data provided by the Bloomberg API is accessed through a "service”. The Schema defines
the format of requests to the service and the events returned from that service. The customer
application's interface to a Bloomberg service is a Service object. Multiple applications can publish to a
single service with the same topics. Platform provides the ability to assign priorities:
Priority
o Integer Value
o Higher the value the more preferred
Group
o Set of publishers for a service that support identical sets of topics
o Possibly different priorities within group
3.2.1.
Registering a Service
There are two ways to registering a service:
a. ServiceRegistrationOptions is one where a setGroupID is to set the identifier for the group that
the application belongs to and the other one is setServicePriority where the priority is set for
the application for this service.
b. ProviderSession is the second way where the registerService (service_name, app_identity,
service_options) helps in registering the service with the ProviderSession and Platform and
getService(service_name) is used to retrieve a Service object for use after it’s been registered.
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Bloomberg Open API – Publishing Developer Guide
3.3.
Topics and TopicList
The concept of a Topic is an “instrument” of data that is to be distributed and all the messages are
created with the topic object. A Topic (Concept) is an instrument of data that is to be distributed. All
messages are created using the topic object.
The TopicList is used to construct a list of topics to be created:
topicList.add("//viper/mktdata/ABCDE Equity",
CorrelationId(1));
It is possible to check status of a topic:
for (size_t i = 0; i < topicList.size(); ++i)
{
int status = topicList.statusAt(i);
if (status == TopicList::CREATED)
The PrvideSession help to create Topics(topic_list, .., ..); and also updates the status in the TopicList.
3.4.
Events and EventFormatter
An event is encapsulates data to be sent to the platform that is created via a Service’s createPublishEvent.
This is populated via the EventFormatter object:
Event event = service.createPublishEvent();
An EventFormatter is constructed with the Event it updates:
EventFormatter = new EventFormatter(event);
The ProviderSession.publish(Event) sends the event to the platform.
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Bloomberg Open API – Publishing Developer Guide
3.4.1.
E
V
E
N
T
Example Event Structure
Action
Method
Get New Message – MSG1
(MessageIterator)
Get Field1
getElementAs
Get Seq1
getElement
Field2
Get Field2
getElementAs
Field3
Get Field3
getElementAs
Get New Message – MSG2
(MessageIterator)
Get Array Field4
getElement
Get Field4 – Element # 1
getValue
Get Field4 – Element # 2
getValue
MSG1
Field1
Seq1(Array)
Seq1[0]
MSG2
Field4 (Array)
Field4[0]
Field4[1]
Figure 3: Event Structure - example
3.4.2.
Event Formatter
Note:
In both deployments, the end-user application and the customer’s active Bloomberg
Professional service (BPS) share the same display/monitor(s).
Event Formatter
Description
.appendMessage(msg_name, topic)
Appends a message of the specified type to the event for the
specified topic
.setElement(element_name, value)
Set the value of a named element
.pushElement(string)
Creates a new element for the EventFormatter.
Pushes one level up in the stack that needs to be popped
All subsequent operations apply to the element at top the stack
.appendElement()
Creates a new Array Element
Pushes one level up in the stack that needs to be popped
.appendValue(value)
Adds the value to the current Array
.popElement()
Removes the current top element from the event formatter stack
Each call to pushElement and appendElement requires one call to
popElement
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Bloomberg Open API – Publishing Developer Guide
4. Local Publishing
Local Publishing responds to subscriptions and can be locally subscribed to. It is displayed in containers
and can use directly in local application. It will be available globally soon and will have full control of
schema, container is Restricted. This is available in Excel and uses BLPAPI. Listed below is a code
example:
Topic topic = session->getTopic(msg);
CorrelationId cid = msg.correlationId(); // Solicited Only
CorrelationId * cidptr = (isSolicited) ? &cid : 0;
Event event = service.createPublishEvent();
EventFormatter eventFormatter(event);
eventFormatter.appendRecapMessage(topic, cidptr);
Bloomberg LP
Bloomberg LP
Customer Site
X-link
Bloomberg
Appliances
(1U)
Existing
Ethernet
Handoff
To Client
For Bloomberg
Terminal
Managed Client Side Platform Net
BBG L3
Switch
Client DMZ Network
Existing
Ethernet
Handoff
To Client
For Bloomberg
Terminal
[Client VLAN Details]
Client Platform Publisher
Bloomberg Professional
Terminals
Application Server
Figure 4: Local Publishing
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Bloomberg Open API – Publishing Developer Guide
4.1.
Publisher Groups
These groups are needed if multiple publishers on the same topic and determine how the Platform
behaves. The publisher will send subscriptions to publishers with the highest priority. If groups are
different, multiple publishers can send to the same topic and if groups are the same, only the
assigned publisher’s data will be used.
Backup Pub
This is a publisher that receives no subscription requests until the primary pub fails. It is achieved by
using a publisher group; the backup simply has a lower priority:
ServiceRegistrationOptions options;
char *groupID = "SomeGroupID";
options.setGroupId(groupID, strlen(groupID));
options.setServicePriority(Priority);
providerSession.regisqterService(serviceName,identity, options);
The presert values for Priority are ‘PRIORITY_LOW’, PRIORITRY_MEDIUM and PRIORITY_HIGH. The
Platform will load balance between all active members of the group with the currently highest
priority.
4.2.
Launchpad Page Publishing
Page Monitor is a Launchpad component that is included as a part of (BPS) Bloomberg Professional
Service. This understands a set schema on Platform for Page Publishing.
Platform on
Appliance
Page Monitor
Page
Publish
er
DMZ
Figure 5: Page Publishing Overview
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Bloomberg Open API – Publishing Developer Guide
Events
PageUpdate
Page Update event
PageUpdate [SEQUENCE]
numCols [INT32]
numRows [INT32]
Number of rows and
columns on the page
rowUpdate [SEQUENCE]
rowNum [INT32]
spanUpdate [SEQUENCE]
attr [ENUMERATION]
bgColor[ENUMERATION]
Span update event
Attributes like background Color,
foreground Color, text etc,.
fgColor[ENUMERATION]
length [INT32]
startCol [INT32]
text [STRING]
RowUpdate
RowUpdate [SEQUENCE]
rowNum [INT32]
spanUpdate [SEQUENCE]
attr [ENUMERATION]
bgColor[ENUMERATION]
fgColor[ENUMERATION]
length [INT32]
startCol [INT32]
text [STRING]
Figure 6: Publishing Schema
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Bloomberg Open API – Publishing Developer Guide
5. Platform Failover
Failover occurs when one of the paired platforms is unavailable for any reason –
Network/Server/Router/Service:
API gets notified of lost connection
API will hunt through list of Appliances
o
Until it finds an active Platform
API will re-establish all subscriptions and API keeps a replay buffer (of limited size).
Platform Groups
Any number of platforms can be grouped together.
A service will be primary on any of the platforms in a group.
All other platforms in the group will receive data from the primary to be distributed to any subscriber
connected to that platform.
In the event of the primary failing, a new platform will become the primary for that service.
The new platform to become primary is guaranteed to be one with a publisher connected to it.
Platform groups are connected either via cross connect in the same site or via Blolomberg network between
sites.
Publisher Groups
Are needed if multiple publishers on the same topic.
How the Platform behaves is determined by publisher groups and priority
The publisher will send subscriptions to publishers with the highest priority
If groups are different, multiple publishers can send to the same topic
If groups are the same, only the assigned publisher’s data will be used
Backup Pub
A publisher that receives no subscription requests until the primary pub fails
This is achieved by using a publisher group
The backup simply has a lower priority
Load Balancing
Giving both publishers the same priority in the same group will achieve load balancing
Each publisher gets topic requests by round robin
The same level of redundancy will be achieved
This is not recommended, if this will result in publishing across sites where such network traffic is an
issue
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Bloomberg Open API – Publishing Developer Guide
Disconnected operation
In the event that a platform cannot connect to Bloomberg
All local publishing will continue
All permissioning will use the last cached copies
Changes to EMRS will not be available
6. Contribution
Contribution is any piece of data that is published to the Bloomberg back end. It is the data that is
submitted to the Bloomberg Ticker plant and provides data for distribution to other Bloomberg clients.
It provides access to contribute data controlled via Enterprise Management and Reporting service
(EMRS) and access to consume controlled via traditional NFPV (a contribution Entitlement function that
displays the attributes for all products.
6.1.
Contribution Example Code
All examples are in C++. However, only language specific differences exist for other programming
languages. The structure of the code is essentially the same. For specific details, please refer to the
standard examples provided with the API in each language specific directory.
a. Create the ProvideSession object
The Assumption is that there exists a sessionOptions object, and a defined event handler…
ProviderSession session(sessionOptions, &myEventHandler, 0);
b. Service registration
A service can be explicitly registered...
ServiceRegistrationOptions serviceOptions;
// Set of publishers for a service that support identical set of topics, but may
have different priorities.
serviceOptions.setGroupId(groupId, groupId.size());
//Integer value, the higher the value, the more preferred
serviceOptions.setServicePriority(priority);
// Assuming user already has service and identity object...
if(!providerSession->registerService(service, providerIdentity, serviceOptions))
{
...
}
...or alternatively, user can specify AUTO_REGISTER_SERVICES on Topic creation...as shown below
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c. Create the TopicList object and register
TopicList topicList;
Topic topic;
// add topic to the resolution list
topicList.add(service + topic, CorrelationId(topic));
// createTopics() is synchronous, topicList will be updated
// with the results of topic creation (resolution will happen
// under the covers)
providerSession->createTopics(topicList,
ProviderSession::DONT_REGISTER_SERVICES,
providerIdentity);
d. Verify Topic resolution
//Parse the topicList to check resolution status of the list of topics
for (size_t i = 0; i < topicList.size(); ++i)
{
int resolutionStatus = topicList.statusAt(i);
if (resolutionStatus == TopicList::CREATED)
{
topic = providerSession->getTopic(topicList.messageAt(i));
} else
{
…
}
}
e. Create the publish Event object
The Event object is the mechanism by which data is communicated to the back end
Service service = session.getService(service);
Event event = service.createPublishEvent();
f. Create the EventFormatter object
This may take place within a loop if multiple topics are being contributed...
EventFormatter eventFormatter(event);
The use of the event formatter object depends on the specific activity taking place.
g. EventFormatter for Market Data contribution
The EventFormatter object allows the developer to format an event message, in this case, Market
Data...
eventFormatter.appendMessage("MarketData", topic);
eventFormatter.setElement("BID", bid_value);
eventFormatter.setElement("ASK", ask_value);
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h. EventFormatter for Page Data contribution
The EventFormatter object for Page Data. The data is similar to XML in structure. Each pushElement
makes that the current element. Each popElement restores the parent element as the current
element..
eventFormatter.appendMessage("PageData", topic);
eventFormatter.pushElement("rowUpdate");
eventFormatter.appendElement();
eventFormatter.setElement("rowNum", 1);
eventFormatter.pushElement("spanUpdate");
eventFormatter.appendElement();
eventFormatter.setElement("startCol", 20);
eventFormatter.setElement("length", 4);
eventFormatter.setElement("text", "TEST");
eventFormatter.popElement();
eventFormatter.appendElement();
eventFormatter.setElement("startCol", 25);
eventFormatter.setElement("length", 4);
eventFormatter.setElement("text", "PAGE");
eventFormatter.popElement();
eventFormatter.popElement();
eventFormatter.popElement();
eventFormatter.setElement("productCode", 1);
eventFormatter.setElement("pageNumber", 1);
i. EventFormatter to Clear a GDCO Page
The EventFormatter object also allows for a GDCO page to be cleared. This unloads any currently
loaded securities :
eventFormatter.appendMessage("MonitorablePageData", topic);
eventFormatter.pushElement("clearMonitorablePage");
eventFormatter.setElement("pageID", gdco); // GDCO number
eventFormatter.setElement("pageSubID", monitor); //Monitor number
eventFormatter.popElement();
j. EventFormatter to Clear a GPGX Page
The EventFormatter object also allows for a GPGX page to be cleared :eventFormatter.appendMessage(“PageData", topic);
eventFormatter.pushElement("clearPage");
eventFormatter.setElement(“contributorId", contributorID); // Contributor no.
eventFormatter.setElement("pageNumber", gpgx); // GPGX number
eventFormatter.setElement(“productCode", product); //Monitor number
eventFormatter.popElement();
k. EventFormatter to load a security on GDCO Page
The EventFormatter object is used to load a security onto a GDCO page, at a specified row :eventFormatter.appendMessage("MonitorablePageData", topic);
eventFormatter.pushElement("loadMonitorableSecurities");
eventFormatter.setElement("pageID", gdco); // GDCO
eventFormatter.setElement("pageSubID", monitor); // Monitor
// A security is being loaded...
eventFormatter.setElement("pageOperation", "ADD");
// identifierType has to match with what is setup on the terminal for the monitor
// on the GDCO# in use.
// Contact the contribution representative and use the appropriate type.
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// If there is a mismatch in the identifierType sent by the application and what is
// on the terminal, the packet will not be displayed on the GDCO.
// Possible values for identifierType are:
//
- PAGE_ACCESS_TYPE_ISIN
//
- PAGE_ACCESS_TYPE_NONE
//
- PAGE_ACCESS_TYPE_BBG_NUMBER
//
- PAGE_ACCESS_TYPE_CUSIP
//
- PAGE_ACCESS_TYPE_TICKER
//
- PAGE_ACCESS_TYPE_NEW_ISIN
eventFormatter.setElement("identifierType", identifierType);
eventFormatter.setElement("identifier", security);
// loadIndicatior specify how to load the securities on the page.
// Possible values are ABSOLUTE_ORDER/MATURITY_ORDER
eventFormatter.setElement("loadIndicator", "ABSOLUTE_ORDER"); //No maturity sorting
eventFormatter.popElement();
l. Publishing the Event
This passes the event object to the back end to be processed :session.publish(event);
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