Exporting Dockerfiles

[MarvinWeitz]

Add the ability to export the current notebook as a Dockerfile. Each cell in the notebook is turned into a line of the resulting Dockerfile. Markdown should be exported as Dockerfile comments. The export functionality is accessed via a custom button

[MarvinWeitz]

Implemented here

[MarvinWeitz]

Additional / Missing features:

• Add linebreaks for each cell's input
• Markdown isn't exported as comments yey
• Export magics as comments

[MarvinWeitz]

Implemented here