Life cycle of a data source

The following actions indicate key points in the life cycle of a data source. The events take place after a data source extension has been implemented, packaged, and installed into the Integrator Acquisition System.

Action	Corresponding life cycle event
The Endeca IAS Service starts.	IAS Server instantiates any `DataSource` that is installed and correctly annotated.
The following items perform the same action. In the IAS Server API - Calling either `IasCrawler.createCrawl()` or `IasCrawler.updateCrawl()`. In the `ias-cmd` utility - Running either `createCrawls` or `updateCrawls`.	IAS Server instantiates the `PipelineComponentConfiguration` specified by the `DataSource`. IAS Server performs data type and constraint validation and also calls `PipelineComponentConfiguration.validate()` to execute any additional custom validation code you wrote in the method's implementation.
The following items perform the same action. In the IAS Server API - Calling `IasCrawler.startCrawl()`. In the `ias-cmd` utility - Running `startCrawl`.	IAS Server re-creates the `PipelineComponentConfiguration` specified by the `DataSource` and re-validates the `PipelineComponentConfiguration` by calling `validate()`. (IAS Server injects configuration property values via reflection before calling `validate()`.) IAS Server calls `createDataSourceRuntime()` on the `DataSource` instance. The resulting `DataSourceRuntime` exists for the duration of the acquisition. If an incremental acquisition is requested, IAS Server calls `checkFullAcquisitionRequired()` on the new `DataSourceRuntime`. The check returns a Boolean value to indicate whether a full acquisition is required or not. If any data source or manipulator in the IAS pipeline returns `true`, IAS Server calls `DataSourceRuntime.runFullAcquisition()`. If all extensions return `false`, IAS Server calls `IncrementalDataSourceRuntime.runIncrementalAcquisition()`. After all records have been processed by all extensions, IAS Server calls `PipelineComponentRuntime.endAcquisition()`. IAS Server passes in an `AcquisitionEndState` value to `endAcquisition()` to indicate whether the extension succeeded, failed, or requires a full acquisition to recover from a failure.
The following items perform the same action. In the IAS Server API - Calling `IasCrawler.deleteCrawl()`. In the `ias-cmd` utility - Running `deleteCrawl`.	IAS Server calls `PipelineComponent.deleteInstance()` when a data source is removed from an application as part of updating or deleting an acquisition, and `deleteInstance()` is also called if the data source type of the acquisition has changed. (The data source type is represented by a `ModuleId` setting in the IAS Server API).