The Transform Router (T-Router) configures engine transformers automatically by retrieving the engine transform configurations from each configured Transform Engine (i.e T-Engine). The engine transform configurations provide the transformer configuration, including the supported transformers and their transform options.
For more information on the format of the transform configuration and instructions on how to create a transform configuration files for a custom engine, see Creating a T-Engine.
T-Engines are added to the T-Router by adding the engine's URL and JMS queue name used by each and every engine. See next section for the URL and JMS queue name property format.
The T-Router supports 2 types of transformers:
- Single-step transformer: This maps T-Requests to a single T-Engine, which can directly transform the
source media typeto thetarget media typewith the providedtransform optionsandsource file size.
For example: image/png to image/png is handled by the IMAGEMAGICK transformer.
- Pipeline transformer: This maps T-Requests to a sequence of intermediate T-Request steps, which are handled by multiple
T-Engines. These transformers handle situations where there is no single engine that can directly transform one media type to another, but that can be achieved through intermediate media types and transformations.
For example: application/msword to image/png can't be directly performed by one single engine, but it can be handled by LIBREOFFICE (which would generate application/pdf) and then PDF_RENDERER.
Single-step transformers map to a transformer, which in turn maps to an engine. Each engine can have multiple transformers defined in its configuration. The single-step transformers are configured automatically from engine transform configuration files.
Pipeline transforms map to a pipeline transformer, which in turn maps to a series of single-step transformers. These are defined through configuration files in the T-Router. This is described in the later section about pipelines.