Add a USER instruction to a dockerfile

Adds a USER instruction to set the user or UID to use when running subsequent instructions and the default user for the container.

Usage

dfi_user(dockerfile, user, group = NULL)

Arguments

dockerfile

A dockerfile object

user

Username or UID

group

Group or GID (optional)

Value

An updated dockerfile object with the USER instruction added

Details

The USER instruction sets the user and optionally the user group for subsequent instructions in the Dockerfile, and as the default user for running the container. This is important for security, as it's a best practice to run containers with non-root users when possible.

If the user specified does not exist in the container, you'll need to create it first using a RUN instruction.

See also

dfi_run() for creating users & Official Docker USER documentation

Other dockerfile instruction functions: dfi_add(), dfi_arg(), dfi_cmd(), dfi_copy(), dfi_entrypoint(), dfi_env(), dfi_expose(), dfi_from(), dfi_healthcheck(), dfi_label(), dfi_maintainer(), dfi_onbuild(), dfi_run(), dfi_shell(), dfi_stopsignal(), dfi_volume(), dfi_workdir()

Examples

# Set user by name
df <- dockerfile() |>
  dfi_from("rocker/r-ver:4.4.0") |>
  dfi_user("r-user")
df
#> FROM rocker/r-ver:4.4.0
#> USER r-user 
  
# Set user and group by ID
df <- dockerfile() |>
  dfi_from("rocker/r-ver:4.4.0") |>
  dfi_user(1000, 1000)
df 
#> FROM rocker/r-ver:4.4.0
#> USER 1000:1000