Command line arguments

If you run loki via yarn or npm, you need to make sure to prepend your argument list with -- so that yarn passes them though to loki. You can also add ./node_modules/.bin to your PATH to be able to run loki directly.

loki test

Capture screenshots and compare them against the reference files.

yarn loki test -- --port 9009

Flag	Description	Default
--host	Storybook host	localhost
--port	Storybook port	None
--reactUri	URI to base of React Storybook. For static build use file:./storybook-static.	None
--reactPort	React Storybook port	6006
--reactNativePort	React Native Storybook port	7007
--reference	Path to screenshot reference folder	./.loki/reference
--output	Path to screenshot output folder	./.loki/current
--difference	Path to image diff folder	./.loki/difference
--diffingEngine	What diffing engine to use, currently supported are pixelmatch, looks-same and gm	pixelmatch
--chromeAwsLambdaBatchSize	Number of stories to test per lambda invocation.	1
--chromeAwsLambdaBatchConcurrency	Number of stories to test in parallel per lambda invocation.	1
--chromeAwsLambdaFunctionName	Name of the use to capture screenshots.	loki
--chromeAwsLambdaRetries	The number of retries for invoking the lambda, in case of failure.	0
--chromeConcurrency	How many stories to test in parallel when using chrome	4
--chromeDockerImage	What docker image to use when running chrome	yukinying/chrome-headless-browser-stable:118.0.5993.117
--chromeDockerWithoutSeccomp	Run chrome docker without unconfined seccomp settings.	false
--chromeDockerUseCopy	Use docker copy instead of volume mount for local stories	false
--chromeEnableAnimations	Enable CSS transitions and animations.	false
--chromeFlags	Custom chrome flags.	--headless --disable-gpu --hide-scrollbars
--chromeLoadTimeout	How many milliseconds loki will wait for the page to load before taking as screenshot.	60000
--chromeRetries	The number of retries for taking the screenshot, in case of failure.	0
--chromeSelector	CSS selector to the part of the DOM to screenshot. Useful you have decorators that should be excluded.	#root > *
--chromeTolerance	How many percent tolerated difference compared to reference image. Behaviour of tolerance depends on diffingEngine.	0
--chromeEmulatedMedia	Emulates the given media for CSS media queries. Set to print to test print styles.	None
--skipStories	DEPRECATED Regular expression for stories that should not be tested, it will be tested against a string with the format ${kind} ${story}.	None
--storiesFilter	Opposite of --skipStories.	None
--configurationFilter	Regular expression for targets that should be tested.	None
--targetFilter	Regular expression for targets that should be tested.	None
--requireReference	Fail stories without reference image, useful for CI.	False, true for CI
--passWithNoStories	If no stories are detected consider this a success.	False
--verboseRenderer	Plain text renderer, useful for CI.	False, true for CI
--silent	Plain text renderer that will only output errors.	false
--dockerWithSudo	Run docker commands with sudo.	false
--dockerNet	Argument to pass to docker --net, e.g. host or bridge.	None
--device	Device/emulator ID to target for screenshots. Useful when running multiple devices on a single machine.	None

loki update

Capture screenshots and update the reference files.

Takes same arguments as loki test.

loki approve

Prunes old and updates reference files with the images generated in the last run.

Flag	Description	Default
--reference	Path to screenshot reference folder	./.loki/reference
--output	Path to screenshot output folder	./.loki/current
--diffOnly	Only approve files that failed loki test before	false

loki init

yarn run loki init path/to/storybook -- --force

Flag	Description	Default
--config	Path to storybook folder	.storybook & storybook
--force	Overwrite loki configuration	false