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Consider the following scenario: - The user selects an image from an external drive - The user selects a drive - The user unmounts/ejects the external drive - The user clicks flash The application state will contain an image path that is no longer accessible, causing an ENOENT error when spawning the CLI process. Change-Type: patch Changelog-Entry: Display a user error if the image is no longer accessible when the writer starts. Signed-off-by: Juan Cruz Viotti <jviotti@openmailbox.org>
Etcher CLI
The Etcher CLI is a command line interface to the Etcher writer backend, and currently the only module in the "Etcher" umbrella that makes use of this backend directly.
This module also has the task of unmounting the drives before and after flashing.
Notice the Etcher CLI is not worried about elevation, and assumes it has enough
permissions to continue, throwing an error otherwise. Consult the
lib/child-writer module to understand how elevation works on
Etcher.
The robot option
Setting the ETCHER_CLI_ROBOT environment variable allows other applications
to easily consume the output of the Etcher CLI in real-time. When using the
ETCHER_CLI_ROBOT option, the --yes option is implicit, therefore you need
to manually specify --drive.
When ETCHER_CLI_ROBOT is used, the program will output JSON lines containing
the progress state and other useful information. For example:
$ sudo ETCHER_CLI_ROBOT=1 etcher image.iso --drive /dev/disk2
{"command":"progress","data":{"type":"write","percentage":1,"eta":130,"speed":1703936}}
...
{"command":"progress","data":{"type":"check","percentage":100,"eta":0,"speed":17180514}}
{"command":"done","data":{"sourceChecksum":"27c39a5d"}}
See documentation about the robot mode at lib/shared/robot.
Exit codes
The Etcher CLI uses certain exit codes to signal the result of the operation.
These are documented in lib/shared/exit-codes.js and are also
printed on the Etcher CLI help page.