.containterignore

[pierreyves-lebrun]

Actual behavior Kaniko currently expects .dockerignore file for excluding files/folders from image builds.

Expected behavior As the industry is moving away from Docker, it would be nice to support .containerignore as an alternate filename.

Additional Information Would you accept a PR that moves the currently hard coded .dockerignore value to a command line argument?

Description	Yes/No
Please check if this a new feature you are proposing	- [x]
Please check if the build works in docker but not in kaniko	- [ ]
Please check if this error is seen when you use --cache flag	- [ ]
Please check if your dockerfile is a multistage dockerfile	- [ ]