IBM BPM, V8.0.1, All platforms > Authoring services in Integration Designer > Services and service-related functions > Access external services with adapters > Configure and using adapters > IBM WebSphere Adapters > Flat Files > Overview of WebSphere Adapter for Flat Files
Technical overview of the WebSphere Adapter for Flat Files
IBM WebSphere Adapter for Flat Files makes it possible for services running on IBM BPM or WebSphere Enterprise Service Bus to exchange data with the local file system.
Services can use the adapter to exchange data with the local file system in two ways:
- Through outbound processing, services running on IBM BPM or WebSphere Enterprise Service Bus use the adapter to perform operations on files in the local file system, for example, to update an order document.
- Through inbound processing, services running on IBM BPM or WebSphere Enterprise Service Bus use the adapter to receive events from the local file system, for example, to be notified that a customer record has been updated.
You configure the adapter to perform either outbound or inbound processing through the external service wizard, launched through IBM Integration Designer. Using the external service wizard, you can create a module, which consists of a project in IBM Integration Designer and a unit of deployment to IBM BPM or WebSphere Enterprise Service Bus. Each module contains components that make up a service for either an import or an export:
- An import is the point at which a SCA module accesses an external service (a service outside the Service Component Architecture module) as if it were local. An import defines interactions between the SCA module and the service provider. An import consists of a binding and one or more interfaces.
- An export, also known as an endpoint, is an exposed interface from a SCA module that offers a business service to the outside world. An export has a binding that defines how the service can be accessed by service requesters, for example, as a web service.
The module is packaged and deployed to IBM BPM or WebSphere Enterprise Service Bus as an enterprise archive (EAR) file.
To represent files that are exchanged between a module and the local file system, the adapter uses business objects. A business object is a logical data container that contains the data that is processed by the adapter.
You can create business objects using the external service wizard or by using the business object editor in IBM Integration Designer.
The adapter uses adapter-specific data bindings and data handlers to transform data from one format to another during inbound and outbound processing. Data bindings are essentially maps that define how a business object is to be formatted. A data binding reads the fields in a business object and populates the corresponding fields in the file. The data binding that is used depends on the internal format of the file. Each data type has an equivalent data binding. You use the external service wizard to configure the data binding.
Data handlers perform the conversions between a business object and a native format. When you select a data type that contains business objects, you must specify the data handler that performs the conversion. Data handlers are provided by IBM BPM or WebSphere Enterprise Service Bus.
- Outbound processing
During outbound processing, the adapter receives a request from the module, in the form of a business object, to perform an operation on a file in the local file system. The adapter performs the requested operation and returns a business object, if applicable, that represents the result of the operation to the component.- Inbound processing
WebSphere Adapter for Flat Files supports inbound event processing. It polls the local file system at specified intervals for events, such as the creation of a file. When it detects an event, it converts the event data into a business object and sends it to the module for processing.- Business objects
A business object is a logical data container that represents the data that is processed by the adapter. The data can represent either a business entity, such as an invoice or an employee record, or unstructured text, such as the body of an e-mail or a word-processing document. The adapter uses business objects to send data to or obtain data from the local file system.- WebSphere Application Server environment variables
WebSphere Application Server environment variables can be used in the external service wizard to specify directory values.- The external service wizard
Use the external service wizard to configure your adapter before it is deployed to IBM BPM or WebSphere Enterprise Service Bus. The wizard examines files on the local file system, builds services (based on search criteria you provide), and generates business objects and interfaces.