Custom Transformers and FME Flow

Liz Sanderson
Liz Sanderson
  • Updated

Question

Are there any special considerations when dealing with custom transformers and FME Flow (formerly FME Server)? Full Guide: FME Flow Troubleshooting Guide

 

Answer

There are two types of custom transformers:

  • Embedded custom transformers are those whose definition is contained within a workspace. The custom transformer can be used within that workspace, but nowhere else. Embedded transformers are coloured green within the workspace.
  • Linked custom transformers are those whose definition is contained within a separate .fmx file. Such a file enables the transformer to be used in multiple workspaces; for example by emailing them to other FME users, or by placing them in a shared directory. Linked transformers are coloured cyan within the workspace.


Q: If I upload a workspace to FME Flow that contains an embedded transformer, is that transformer available to the workspace on Flow?
A: Yes. If the custom transformer is an embedded transformer, it is self-contained within the workspace - all you need to do is publish the workspace to FME Flow and it will work.

Q: How do I upload my linked transformers to FME Flow?
A: To quickly allow all workspaces on an FME Flow server to have access to a linked transformer, upload it to Resources > Engine > Transformers in the Flow UI. For other options or more information, see this step-by-step guide.

Q: What happens if there are two definitions of the same custom transformer, one in the repository directory and the other in the shared directory?
A: FME Flow will always try to find the transformer in the FME_SHARED_RESOURCE_DIR first. If it does not find it, it will look for the transformer defined in the repository resource directory.

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