January 29, 2012
When implementing process automation initiatives, it is important to have a reuse strategy – why? Because, the process flows are a rich minefield for reusing services and common interfaces across a variety of use cases. It can also act as a service provider for other teams to invoke/integrate a common set of processing flows.
Host business process definitions and instances
- Provide a modeling and execution environment for designing and implementing business processes
- Implement a generic data structure for manipulating & orchestrating workflow state
- Provide the ability to reuse a workflow patterns across business processes. E.g. enable reuse via sub-processes, process extension points, etc.
- Provide the ability to access and orchestrate activities requiring interaction with data services and business rules, and legacy services
Act as services consumer & provider
- Host process orchestrations, while consuming persistence, validation, and security services
- Abstract legacy capabilities and reduce tight coupling between internal systems
- Publish and consume business events to reduce application to application coupling
Evolve a reusable asset catalog
- Ensure technology components and APIs have domain relevance – data, events, and relationships are fundamental abstractions need to be brought together
- Reduce learning curve for application developers to identify, evaluate, and integrate process definitions and services from a library of reusable assets
November 7, 2011
Many teams are pursuing BPM and SOA based initiatives to automate, streamline, and standardize business processes. As more solutions start to embark on BPM-based solutions, there is a need for a common set of software components that aid in hosting and managing business processes. The following are capabilities that need to be present in such a solution:
- Common messaging architecture & utilities for facilitating the development and maintenance of stateful business processes & stateless services.
- Support business process orchestrations that join across multiple services (data services, business services, legacy services, etc.). This is essential for orchestrating complex
- Handle workflow and system business process events via a configuration driven Event Handler Service, enabling reuse of event handler processes
- Provide ability to reuse sub-processes across larger business processes.
- Runtime metrics including reporting and the ability to perform diagnostic troubleshooting
- Reusable schemas for request dispatching, event handling, generic transport listeners, metrics, and error handling
- Supports synchronous and asynchronous request/reply & fire/forget message exchange patterns
- Provides the ability to create reusable components for assembling new business processes
- Standard client interfaces across multiple transports such as HTTP and EMS
- Ability to query various data sources, rules engine, as well as write custom java code to integrate with existing functionality
- Provides interface for executing administrative functions
- Provides developer tools for WSDL generation, unit testing, deployment, & viewing metrics
December 20, 2010
Implementing business process re-engineering and/or automation involves several moving parts from a technology perspective – stateful business process data, interfaces for external systems/user interfaces to interact with process information, and rules that determine several aspects of process behavior.
Here are some practices to avoid/minimize when pursuing BPM projects:
- Building monolithic process definitions – as the number of process definitions increase there will be opportunities to refactor and simplify orchestration logic. As projects start to build on existing processes, there will be an increasing need for modular process definitions that can be leveraged as part of larger process definitions.
- Placing business rules that validate domain objects in the process orchestration graphs. This will effectively tightly couple rules and a specific process hurting the ability to reuse domain-specific rules across process definitions. Certain class of rules could change often and need to be managed as a separate artifact.
- Invoking vendor specific services directly from the process definition. Over time this will result in coupling between a vendor implementation and multiple process definitions. This also applies to service capabilities hosted on legacy systems. Hence, the need to use a service mediation layer.
- Defining key domain objects within the scope of a particular process definition. This will result in multiple definitions of domain objects across processes. Over time, this will increase maintenance effort, data transformation, and redundant definitions across processes and service interfaces.
- Integrating clients directly to the vendor-specific business process API. This will result in multiple clients implementing boiler plate logic – better practice will be to service enable these processes and consolidate entry points into the BPM layer.
This isn’t an exhaustive list – intent is to to highlight the areas where tight coupling could occur in the business process layer.
November 13, 2010
New episode added to the Software Reuse Podcast Series on designing reusable exception handling for SOA efforts. It elaborates on using a simple set of components for handling exceptions, capturing relevant metadata, and determining notifications.
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November 6, 2010
When working on implementing business process automation solutions, the team needs to bring together several related concepts: chief among them are events, process instances, and service capabilities. I like to think of them in the context of an overall enterprise architecture being aligned with individual solutions and projects. Bringing these concepts together holistically has several benefits:
- Better alignment between BPM & SOA initiatives (wrote earlier about the risks of not doing so)
- Consistent interfaces for event producers and consumers (e.g. clients who initiate changes to data or alter a process will be able to reuse a standardized set of messages)
- Simpler solution architecture – aligning data models across event processing and services will reduce data transformation needs. It will greatly reduce the need for data mapping and complex adapters.
Events can be internal or external and can impact business processes in several ways. An external event could initiate a business process (thereby a new process instance is created), or alter an existing process (execution is moved from some kind of wait state or an existing instance could be terminated). These events could be data, state, or a combination of the two impacting a business process. The business process instance might take an alternate path or spawn a new instance of another process as appropriate.
Process instances themselves can be implemented by leveraging several service capabilities. These service capabilities need to share a consistent set of domain-relevant interfaces. The process instances can then be loosely coupled with services thus enabling the service implementations to evolve over time. As state changes happen in a process instance, outbound events can be generated – these are publications or notifications that are of interest to potentially multiple consumers. Service capabilities can be leveraged for not just creating/changing data but also when encapsulating business rules for decision steps, as well as for publishing messages to downstream systems/processes.
October 9, 2010
Business processes hosted in a BPM container (whether running in-process or as an external engine) need to be exposed to consumers in your enterprise. Here’s where your SOA efforts can come in handy – these business processes can be exposed as services via interfaces provided in the service mediation layer. Doing so decouples the vendor specific business process interfaces from enterprise consumers and allows for additional horizontal capabilities to be hooked in (metrics capture, monitoring, authentication, authorization etc.).
So what can these services do? Here’s a very simplified diagram of how these services fit in:
These services are commonly referred to as Task Services and they encapsulate operations on business processes. Common domain-relevant schemas can be leveraged from other services efforts – facilitating consistency and reduce data transformations between the business and services layers.
August 21, 2010
The word ‘governance’ seems to conjure up all sorts of negative images for IT folks – needless bureaucracy seems to top that list. However, without lightweight governance, SOA and systematic reuse efforts will fail to achieve their full potential. Can you spot signs that indicate need for governance? I believe so and here are five:
- Every project seems to reinvent business abstractions that are fundamental to your problem domain. No sharing or consistency of information models – this will be painfully evident when projects are happening back to back and your teams seem to be running into overlapping data modeling, data definition, and data validation issues.
- Directly linked to above – is service definitions seem to not reuse schemas – i.e. each service has a unique schema definition for a customer or product (or some key object from your domain) and your service consumers are forced to deal with multiple conflicting schemas.
- Legacy capabilities are leveraged as-is without mediation – increasing coupling between consumers and legacy systems. Tell tale sign here is if you see arcane naming and needless legacy data attributes sprinkled all over service interfaces.
- Services seem to have inconsistent runtime characteristics – new service capabilities are added without regard to performance requirements – issues tend to manifest in production where users or entire processes/applications get impacted to service behavior.
- Business processes bypass a service layer and directly access underlying data stores – if you have seen a business process invoking several stored procedures, doing FTP, publishing to multiple messaging destinations – all from a monolithic process definition that is a clear sign that governance is non existent.
These are few signs but key indicators that services are being built in a tactical fashion. In a follow up post, will expand on how governance can be leveraged appropriately to address these issues.