Top 30 Oracle Service Bus (OSB) Interview questions and answers

28 Oct 2020 oracleappsadmin

The blog provides the commonly asked Oracle SOA Oracle Service Bus (OSB)   Interview questions & answers to be helpful for beginners and experienced professionals.

Refer the below given blog for more OSB Interview Questions and Answers

OSB Interview Questions and Answers -Set 2

What is the role of Oracle Service Bus (OSB) in SOA Suite ?

  • Oracle Service Bus (OSB) is a configuration based policy driven enterprise service to manage the SOA Life Cycle management
  • Oracle Service Bus (OSB) follows the SOA principles of developing loosely coupled standard based services executing the business functions through service consumers.
  • Oracle Service Bus (OSB) provides service discovery, service provisioning and service deployment capabilities
  • Oracle Service Bus (OSB) provides the message brokering , message transformation and message routing  across heterogenous environments

What are the features of Oracle Service Bus (OSB) ?

 The Oracle Service Bus (OSB) provides the below features:

  • Provides Service Orchestration
  • Provides location transparency 
  • Provides Message Transformation
  • Provides message processing using multiprotocol
  • Provides support for Dynamic routing of the message
  • Provides Service Level Agreement
  • Provide Service Security using OPSS and OWSM

Explain how Oracle Service Bus (OSB) supports Adaptive Messaging ? 

The Oracle Service Bus (OSB) provides support for message handling and message transformation between client and services. For instance, the Client send the SOAP message over HTTP and transforms message and invoke JMS Adapter to put the message into Queue 

Another example could be of transforming the REST/ JSON message into SOAP /XML message for processing to service consumers. 

The OSB communication patterns like Request-Response, Publish -Subscribe , Split-Join, Synchronous – Asynchronous also considered as part of Adaptive messaging.

What are the levels where Service Security can be applied in Oracle Service Bus (OSB) ? 

The Oracle Platform Security Services (OPSS) and Oracle Web Service Manager (OWSM) allows Oracle Service Bus (OSB) to apply the service security at below given levels:

  • Transport Level Security  (includes SSL , Basic Authentication /Authorization, Custom Security) 
  • Message Level Security ( includes WS-Security , SAML, UserId /Password , Encryption, Custom Security) 
  • Console Level Security ( includes Single-Sign-On , Role based Access) 
  • Policy Security

What is Service Virtualization in Oracle Service Bus (OSB) ?

Service Virtualization provides agility through message manipulation and control by providing the flexibility to control message validation, message transformation, message content based routing, message parallel processing , error handling in the message flow. 

What features are provided by Configuration Framework in Oracle Service Bus (OSB) ?

The configuration framework in Oracle Service Bus provides the below features:

  • The Configuration framework provides control over the Service Bus Environment and associated resources
  • The configuration changes made within the session does not interrupt the running services
  • The Test Control allows user to validate the resources, expressions, pipelines and split -joins 
  • The Test Control allows to execute and validate the result data
  • The Import/ Export Tool allows to move the configuration data from one environment to another 
  • The configuration framework also includes metadata -driven interface for service discovery, publishing and UDDI registry synchronization

Describe the steps for message processing in Oracle Service Bus (OSB) ?

The Oracle Service Bus (OSB) performs the Adaptive Messaging , message transformation, and route messages based on message content which includes the below given sequence of steps :

  • The Oracle Service Bus (OSB) receives the message from client though Transport Protocol
  • The Transport Provides passes the inbound message  , communicates with the client end point considering as the entry point for the message
  • The Binding Layer preforms the Pack/Unpack of the messages , manages message security and pass on the message content to the Pipeline
  • The pipeline performs validation, transformation, logging, reporting and message routing to the target end point
  • The received response is sent back to the Client

What is Proxy Service in Oracle Service Bus (OSB) ?

The Proxy Service in Oracle Service Bus acts as the interface for the service consumers that connects with managed back-end services.  Proxy Services provides “Location Transparency” through isolation of Service Consumers from Service Providers and act as a proxy layer to transport the message

The Proxy Service interface can be defined as Web Services Description Language (WSDL)  or as Web Application Definition Language (WADL) using the transport protocol.

The Proxy Service can route message to multiple Business Services as per defined interfaces.

What is Business Service in Oracle Service Bus (OSB) ?

The Business Service in Oracle Service Bus acts as the interface which connects to the service producers to perform business processes. The Business Service interface can be defined as Web Services Description Language (WSDL)  or as Web Application Definition Language (WADL) using the transport protocol.

The Business Service is similar to Proxy Service but provides additional options for message
handling, endpoint throttling, and result caching, which help improve performance.

What is OSB Service Orchestration ?

The Oracle Service Bus (OSB) provides the Orchestration where single Proxy Service can route messages to multiple Web Services  based on the message content or message operations defined as per business validation / logic.

Explain Inbound Transport Layer in Oracle Service Bus (OSB) ?

The Inbound Transport Layer acts as the communication layer between client services ( service consumers) and Oracle Service Bus and passes the inbound message (raw bytes of message)  , communicates with the client end point considering as the entry point for the message.

The Inbound Transport Layer provides support for the transport protocol like HTTP, FTP, JMS, File and other protocols.

The Inbound Transport Layer returns the response messages to the service consumers

The Inbound Transport Layer handles transport headers, message metadata, endpoint URIs

Explain Outbound Transport Layer in Oracle Service Bus (OSB) ?

The Outbound Transport Layer acts as the communication layer between external services ( service producers) and Oracle Service Bus

The Outbound Transport Layer acts passes the message (raw bytes of message) from Service Bus to Business Service or Proxy Service. 

The Outbound Transport Layer provides support for the transport protocol like HTTP, FTP, JMS, File and other protocols.

The Outbound Transport Layer returns the response messages to the service producers

The Outbound Transport Layer handles transport headers, message metadata, endpoint URIs

What functions are performed by Binding Layer in OSB message processing ?

The binding layer performs the below functions for Inbound and Outbound messages:

  • Message Pack / Message Unpack
  • Message Security
  • Move Message to the Pipeline ( Request-Response) 

What is message flow ? 

A message flow determines on how a message is going to be Validated, Transformed and routed among services. A message flow can be defined using Pipeline and Split -Join for the Parallel Processing of the message.

What is the role of Pipeline in Oracle Service Bus (OSB) ?

The pipeline determines the transformation and message routing logic  and provides message handling options ( publishing, logging, reporting, alerts, and service exception )

What are the primary elements in pipeline for the message flow ?

The pipeline includes the below given elements for the message flow: 

  • A Start Node
  • A Pipeline Pair : includes one for request and one for receiving response
  • A Branch Node: based on operations invoking specified branch for message processing
  • A Route Node: includes the target end point definition
  • An Error Handler : handles run time errors 

What is Split-Joins in Oracle Service Bus (OSB) ?

The Split-Join is useful for splitting a message payload and processing through multiple operations and the received responses are combined for get the final result. 

What are the primary elements in Split – Join for the message flow ?

The split -Join includes the below given elements for the message flow: 

  • A Start Node
  • A Receive Node : to receive inbound messages
  • A Reply Node: to send outbound messages
  • A Scope Node: creates a context that influences the behavior of enclosed elements
  • A Parallel Node: placeholder for processing branches

What are the available Service Types in Oracle Service Bus (OSB) ?

The below given are the OSB Service Types: 

  • Web Based Services:  
  • Any SOAP Service 
  • Any XML Service  
  • Messaging Service 
  • Native REST Service

What is Message Enrichment and how it is supported in OSB ?  

The Message Enrichment helps in retrieving additional information from the existing service using Service Callout option

Pass the Additional Received Information to the Inbound Message

Route the Message to invoke the Target Business Service 

Route the Message to applications supporting Java using Java Callout

 

When should we use the Message Service Type? 

The Message Service Type should be used when one of the Request or Response messages are Non-XML as Service bus cannot identify automatically and performs the SOAP Header Validation.

What are available Content Types  for the request and response message? 

The below content types are supported:

  • Binary
  • Text
  • MFL
  • XML
  • Java
  • None

What response content type is supported by File , FTP and SFTP Transport Proxy Service?

The Transport Proxy Services for Email, File, FTP, SFTP with a message service type support only one way message processing and returns NO response.  Thus, the content type for response message should be set to None

When should we use Any SOAP or Any XML Service Types in OSB ?

When a single port is to be exposed for multiple enterprise applications, Any SOAP or Any XML should be used.  

For Any SOAP , must specify the SOAP 1.1 or SOAP1.2 specification.