The Log Debug option returns a lot of BADNEWS errors. What do they mean and should I be worried?

Background

The Log Debug option causes additional messages to be logged in the FME log file.

In general, you should only use Log Debug when an error has already occurred, and you are seeking further information. The additional messages may provide extra details that help you resolve problems in your translation.

It is not recommended to leave this option enabled permanently. BADNEWS "errors" (one type of additional debug message) are usually part of the regular internal workings of FME, yet their wording reads like a serious error. For example, BADNEWS: End of File Reached, is a message common to almost every translation.

So, Log Debug is of little benefit to the average user and can lead to concerns that the translation has failed.

Our advice is not to use Log Debug if your translation appears to run correctly. Only if there is a regular warning or error should Log Debug be used to obtain further information.

How to Enable or Disable Log Debug

Workbench Methodology

Debug logging can be enabled/disabled as follows in FME Workbench:

1. Click the settings wheel in the Translation Log window to edit log options. 
Or, select Utilities > FME Options > Translation (or Tools > FME Options > Translation in 2025.0 and older).

2. Check (or uncheck) the "Log Debug" option under Log Settings

3. Click OK to close the FME Options dialog

Saved Workspaces

Once activated, Log Debug is enabled in the current workspace and saved as an option within that workspace. If the workspace is then published and run on FME Flow, in the FME Quick Translator, or from the command line, the log will include debug information.

Therefore, care should be taken to disable Log Debug before sharing a workspace or using it in production, as Log Debug may impact workspace performance or include too much detail for other users.

To use Run Workspace with Log Debug enabled in FME Flow, set the Log Debug toggle to True under the Advanced parameters. Then, click "Run." This will enable Log Debug only for that job and reduce the likelihood that Log Debug remains enabled.

Command Line Methodology

Debug logging can be enabled using the keyword FME_DEBUG on the command line. There are various parameters that are available to go with this keyword, some of which are:

• ALL (FME 2024.1+, includes all recommended flags)
• EXTRA (FME 2024.1+, includes selected extra flags)
• EVERYTHING (FME 2024.1+, includes all known flags)
• FME_DEBUG
• MAPPING_FILE
• BADNEWS
• FME_STACK_TRACE
• UNGROUPED
• UNCORRELATED
• DUMP_SCHEMA
• XSD_VERBOSE
• HTTP_DEBUG
• FTP_DEBUG

Using these individually would let you be more selective about the types of logging than the Log Debug option as a whole allows.

Example 1: Applying BADNEWS logging to a translation:

In FME 2024.1 and newer:

fme [myworkspace.fmw] FME_DEBUG ALL

And before FME 2024.1:

fme [myworkspace.fmw] FME_DEBUG FME_DEBUG

...applies BADNEWS logging to a translation.

Example 2: Using multiple options:

In FME 2024.1 and newer:

fme [myworkspace.fmw] FME_DEBUG ALL +FME_DEBUG EXTRA

And before FME 2024.1:

fme [myworkspace.fmw] FME_DEBUG FME_DEBUG +FME_DEBUG HTTP_DEBUG

...applies multiple instances of FME_DEBUG with a + symbol.

Old School Methodology

The older style of setting options in FME involves what are called Directives. The Directive to turn on Log Debug is called FME_DEBUG. This can be used inside a Mapping File, for example, in FME 2024.1 and newer:

FME_DEBUG ALL

And before FME 2024.1:

FME_DEBUG FME_DEBUG MAPPING_FILE BADNEWS UNGROUPED UNCORRELATED DUMP_SCHEMA

You could also set this in the dialog under Tools > Edit Header in Workbench.