Instruction WRITE
See the section on file options.
The WRITE instruction writes a fixed string to the given path.
A file can be added to the build output with COPY, but sometimes we just need
to write a short value, and COPY might feel like overkill.
Using WRITE, we can put values directly into files:
WRITE "hello world" hello.txt
Be aware that WRITE does not add a newline at the end of your input.
For text files, it is almost always preferred to end with a newline.
To do this, add \n at the end of the quoted string:
WRITE "hostname\n" /etc/hostname
The same file options as COPY and RENDER are accepted:
WRITE --chmod 0600 --chown service:root "API-TOKEN" /etc/service/token.conf