SOA Design & Architecture (S90-03A) Practice Questions
Prepare for S90.03 with more than an answer.
- Exam fee
- $300 USD
- Level
- Professional
- Valid for
- Lifetime
Domains covered on the exam 5
- Fundamental SOA, Services & Microservices20%
- Service Technology Concepts20%
- SOA Design & Architecture25%
- Advanced SOA Design & Architecture20%
- SOA Design & Architecture Lab15%
- 1
In an event-driven architecture, a service publishes an 'OrderCreated' event. Several other services need to react to this event: one to update inventory, one to process payment, and another to send a confirmation email. Which communication pattern best describes this scenario?
Show answer details
Correct answer: C
The Publish-Subscribe (Pub/Sub) pattern allows a message producer (the publisher) to send a message without knowing who the consumers (subscribers) are. The 'OrderCreated' service publishes an event to a topic, and multiple subscriber services (Inventory, Payment, Email) independently receive and process that event. This highly decouples the services from one another.
- 2
True or False: A primary benefit of building an agnostic service is that its logic is specifically tied to one business process, which guarantees its optimal performance within that context.
Show answer details
Correct answer: B
This statement is false. The defining characteristic of an agnostic service is that its logic is intentionally NOT tied to any single business process. It is designed to be generic and context-neutral to maximize its potential for reuse across multiple business processes, which is a core tenet of the Service Reusability principle.
- 3
During the analysis phase of a project, architects identify a set of services that encapsulate core business entities like 'Customer', 'Product', and 'Order'. These services are designed to be agnostic and reusable across the entire enterprise. According to the standard service layers model, what type of services are these?
Show answer details
Correct answer: D
Entity Services are designed to manage and expose information about specific business entities (nouns), such as Customer or Product. They are a cornerstone of a reusable service inventory because they provide a single, authoritative source for key business data, making them highly agnostic and composable.
- 4
A project requires integrating a cloud-based SaaS application with an on-premise legacy database. The SaaS application sends notifications via a modern webhook (HTTP POST with a JSON payload), while the legacy database can only be updated via a stored procedure call. An architect needs to design a solution that receives the webhook, transforms the JSON payload into the format required by the stored procedure, and then invokes the procedure. Which pattern from the Enterprise Integration Patterns (EIP) catalog is most central to this solution?
Show answer details
Correct answer: B
The Message Translator pattern is used to translate a message from one format to another. In this scenario, the core task is to transform the incoming JSON payload from the webhook into a different data structure suitable for the legacy database's stored procedure. This is a classic application of the Message Translator pattern, often implemented within an integration layer or ESB.
- 5
When designing a service composition, an architect must decide between orchestration and choreography. Which of the following statements accurately describes the primary trade-off between these two approaches?
Show answer details
Correct answer: B
This statement correctly identifies the core trade-off. Orchestration uses a central controller (an orchestrator) to manage the process flow, providing clear visibility and control but creating a dependency on that controller. Choreography relies on services reacting to events from other services without a central controller, which increases service autonomy and decoupling but can make the overall process flow harder to monitor and debug.
- 6
During a design review for a new enterprise-wide service inventory, an architect proposes a data model that strictly enforces a canonical format for all business entities. Another architect argues this approach will create excessive transformation logic for services that use domain-specific variations of these entities. Which two service-orientation principles are most directly in tension in this scenario? (Select TWO)
Show answer details
Correct answer: A, B
The principle of Service Reusability, particularly through the application of a Standardized Service Contract, encourages the use of a canonical data model to ensure consistency and interoperability across the enterprise. However, this can conflict with Service Autonomy, which posits that services should have significant control over their own logic and resources. Forcing a service to conform to a rigid, enterprise-wide model can limit its ability to evolve independently and may require it to contain complex, non-native transformation logic, thus reducing its autonomy.
- 7
A financial services company is building a loan origination process as a service composition. The process involves a credit check service, an underwriting service, and a funding service. To ensure data consistency, the entire process must be atomic; if the funding service fails, the credit check and underwriting actions must be rolled back. However, the credit check service is a third-party API that does not support two-phase commit (2PC) transactions. Which design pattern is most appropriate for managing this long-running, distributed transaction?
Show answer details
Correct answer: B
The Saga pattern is designed to manage data consistency across microservices in distributed transaction scenarios without relying on traditional locking mechanisms like two-phase commit (2PC). It sequences a series of local transactions. If any transaction fails, the saga executes a series of compensating transactions to revert the preceding transactions. This is ideal for the described scenario where a participating service does not support 2PC.
- 8
An architect is designing a service that retrieves customer profiles. The initial design exposes a rich data model directly from the underlying CRM database. A senior architect flags this as a violation of the Service Abstraction principle, specifically citing that it leaks implementation details. Which meta abstraction type is primarily being violated by exposing the raw database model?
Show answer details
Correct answer: B
Technology Abstraction is concerned with hiding the specific technologies used to implement a service. By exposing a data model that directly mirrors the CRM database schema, the service contract is tightly coupled to the underlying database technology (e.g., its table structure, column names, and data types). This violates Technology Abstraction because changes to the CRM database schema would directly impact service consumers.
- 9
True or False: The application of the Service Discoverability principle is solely concerned with publishing a service's technical endpoint (WSDL or OpenAPI specification) to a central registry.
Show answer details
Correct answer: B
This statement is false. Service Discoverability goes beyond simply publishing a technical endpoint. It requires supplementing services with communicative metadata that allows them to be effectively discovered and interpreted. This includes business-level information, quality-of-service details (SLAs), versioning information, and usage policies, not just the technical contract.
- 10
A logistics company needs to provide a real-time package tracking service to its partners. The underlying system is a legacy mainframe application that processes data in batches every 15 minutes. Direct, real-time queries to the mainframe are not possible. The company wants to expose a modern, stateless REST API for tracking. Which combination of design patterns is the best approach to bridge this gap?
Show answer details
Correct answer: C
This is the most comprehensive solution. A Service Agent runs on a schedule (e.g., every 15 minutes) to perform a Data Transfer from the mainframe batch system. The retrieved data is then stored in a cache (State Caching). The modern REST API (a Service Façade) then serves requests by querying this cache, providing a real-time experience to consumers while decoupling them from the legacy system's batch nature.
