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Creating a Custom Transformer

The easiest way to create a custom transformer is from an existing workspace, and by choosing transformers that you are often reusing, or transformers that take up a lot of space on the canvas.

Open a workspace.
Select a group of transformers: click and hold the left mouse button, and drag a box around the transformers. Release the mouse button.
Press Ctrl + T, or right-click and select Create Custom Transformer.

In the Transformer Properties dialog, enter a name for the custom transformer.

Creating Category Names: In the Category field, you can choose an existing category in which to store the transformer; however, you can also enter your own category name. The category will be added to the Transformer Gallery. Note that you will have to restart Workbench to see the new category.

You can also enter other optional information, including a description. This information is the same as Workspace Properties.

Click OK. In this example, Workbench opens a new tab named PointCloudThinning and the original group of transformers is shown on the canvas. Note that the properties buttons have turned yellow again, so you will have to reconfirm the parameters.

The input and output (if included) arrows are for reference only, to reflect the input/output to the custom transformer in the main workspace.

The original group of transformers is replaced with the new custom transformer in the main workspace:

Note: You cannot include any reader or writer feature types in a custom transformer.

The Navigator includes details about custom transformers: it lists the transformers (and their attributes) that are part of the custom transformer, and its own parameters are included under a Transformer Properties icon. See Workspace Properties for more information.

In the main workspace, the custom transformers are listed in the Navigator (much like any other transformer), except they appear as green icons:

Other Ways to Create Custom Transformers

Right-click in your main workspace and choosing Insert Custom Transformer. You can build the transformer workflow separately, and then manually connect it to both the input and output transformer arrows, and in the main workspace.
Create a bookmark and turn its contents into a custom transformer.

Embedded or Linked?

Custom Transformers can be defined in two forms: embedded and linked.

Embedded is the default state of a Custom Transformer. This means that the transformer is stored as part of this workspace, and is, therefore, not otherwise available to other users.

A linked transformer is one whose definition is saved as an external file. Each reference to the transformer from a workspace is a link to that definition and if the definition changes, then so does the workspace behavior. Exporting transformers is the way to share them with other users.

You can export an embedded transformer to a file by clicking File > Export as Custom Transformer on the menu bar. You can embed a linked transformer by right-clicking the transformer and selecting Embed.

What can you do with a custom transformer?

After you have created a custom transformer, you can:

edit its definition in separate tabbed window
duplicate it (copy/paste it) within the same workspace
select it from the Transformer Gallery, and include it any number of times
copy/paste it into a new workspace (its elements are also copied)
share it with other users
export it as a separate .fmx file (by default, it will be stored in My Documents\FME\Transformers)