Output Controls

drydock keeps stdout machine-parseable for structured output. Diagnostics and failure summaries go to stderr unless status text is the primary output.

Formats

Use -o or --output to select the format supported by each command:

Command area Output formats
get apps, get images table, name, json, yaml
test apps, test app text, json, yaml
diff apps, diff app unified, markdown, json, yaml
diff images unified, markdown, json, yaml, name
diag text, json, yaml

-o name is intended for list-style output. It is not supported for manifest diffs, and removed-only image changes print no names while still counting as a diff for exit-code behavior.

Diff Controls

Unified manifest and image diffs support terminal color with --color=auto|always|never. The default auto colors only when stdout is a terminal. JSON and YAML outputs never include ANSI color.

Use markdown output when the result will be read in a pull request comment:

drydock diff apps --repo . --ref HEAD --ref-orig origin/main -o markdown
drydock diff images --repo . --ref HEAD --ref-orig origin/main -o markdown

Exit Codes

Diff commands use fixed exit codes:

Code Meaning
0 Success, no diff
1 Success, diff found
2 Runtime, config, or render error

Use --exit-code=false for local inspection when a diff should not fail the command.

For the full command reference, see the CLI usage guide . For action outputs and PR comment controls, see the GitHub Actions guide .