Log Failure Level

The failure_level key specifies the severity threshold that, when met or exceeded, causes Antora to exit with a non-zero (i.e., failure) exit code.

To be clear, this setting doesn’t stop Antora from running. Rather, it merely impacts the exit code value of the process in which Antora is running. It’s up to the shell to interpret this value, as most CI environments do.

Default failure level

Explicitly assigning a value to the failure_level key is optional. If it isn’t set in the playbook or specified using the --log-failure-level option or ANTORA_LOG_FAILURE_LEVEL variable, Antora assigns the value fatal to the key at runtime. If a logged message meets the fatal severity threshold, Antora will exit with a non-zero exit code.

failure_level key

The failure_level key is configured under the runtime and log keys in a playbook.

Example 1. antora-playbook.yml
runtime:
  log:
    failure_level: error

The key accepts the following built-in values:

  • fatal (default)

  • error

  • warn

  • none

These values correspond to the severity levels Antora assigns to log messages. Except when the value is none, Antora exits with a non-zero exit code if a message is logged that meets or exceeds the value assigned to failure_level. When the value is none, Antora always exits with zero exit code, even when an unhandled error is thrown. Note that when Antora’s logger is turned off, the failure_level key and its value aren’t applied.

Force zero exit code

When the failure_level key is assigned the value none, Antora always exits with the exit code zero (0), even if a fatal error is encountered.

Specify a failure level

Let’s assign the value warn to the failure_level key in the playbook shown in Example 2.

Example 2. Assign warn severity threshold to failure_level key
runtime:
  log:
    failure_level: warn

Antora will finish generating the site, as long as it doesn’t encounter any fatal errors, and exit with a non-zero exit code if any messages are logged with a severity of warn or greater. If no warning, error, or fatal messages are logged, Antora exits with a zero (0) exit code. That is, your site built successfully without any errors or potential problems!

Log failure level option

Alternatively, you can use the --log-failure-level option from the CLI to assign a failure threshold.

$ antora --failure-level=warn antora-playbook.yml

The --log-failure-level option overrides the value assigned to the failure_level key or the ANTORA_LOG_FAILURE_LEVEL environment variable.