pack: Add '--format' option and Docker output support.

* guix/docker.scm: Remove dependency on (guix store) and (guix utils).
Use (guix build store-copy).  Load (json) lazily.
(build-docker-image): Remove #:system.  Add #:closure, #:compressor, and
'image' parameters.  Use 'uname' to determine the architecture.  Remove
use of 'call-with-temporary-directory'.  Use 'read-reference-graph' to
compute ITEMS.  Honor #:compressor.
* guix/scripts/pack.scm (docker-image): New procedure.
(%default-options): Add 'format'.
(%formats): New variable.
(%options, show-help): Add '--format'.
(guix-pack): Honor '--format'.
* guix/scripts/archive.scm: Remove '--format' option.  This reverts
commits 1545a012cb7cd78e25ed99ecee26df457be590e9,
01445711db6771cea6122859c3f717f130359f55, and
03476a23ff2d4175b7d3c808726178f764359bec.
* doc/guix.texi (Invoking guix pack): Document '--format'.
(Invoking guix archive): Remove documentation of '--format'.

1 files changed, 17 insertions, 17 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index 3382ac414e..45d171c52d 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -2435,6 +2435,22 @@ guix pack -S /opt/gnu/bin=bin guile emacs geiser
 @noindent
 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
 
+Alternatively, you can produce a pack in the Docker image format, as
+described in
+@uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
+version 1.2 of the specification}.  This is what the following command
+does:
+
+@example
+guix pack -f docker guile emacs geiser
+@end example
+
+@noindent
+The result is a tarball that can be passed to the @command{docker load}
+command.  See the
+@uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
+documentation} for more information.
+
 Several command-line options allow you to customize your pack:
 
 @table @code
@@ -2537,7 +2553,7 @@ what you should use in this case (@pxref{Invoking guix copy}).
 
 @cindex nar, archive format
 @cindex normalized archive (nar)
-By default archives are stored in the ``normalized archive'' or ``nar'' format, which is
+Archives are stored in the ``normalized archive'' or ``nar'' format, which is
 comparable in spirit to `tar', but with differences
 that make it more appropriate for our purposes.  First, rather than
 recording all Unix metadata for each file, the nar format only mentions
@@ -2553,9 +2569,6 @@ verifies the signature and rejects the import in case of an invalid
 signature or if the signing key is not authorized.
 @c FIXME: Add xref to daemon doc about signatures.
 
-Optionally, archives can be exported as a Docker image in the tar
-archive format using @code{--format=docker}.
-
 The main options are:
 
 @table @code
@@ -2584,19 +2597,6 @@ Read a list of store file names from the standard input, one per line,
 and write on the standard output the subset of these files missing from
 the store.
 
-@item -f
-@item --format=@var{FMT}
-@cindex docker, export
-@cindex export format
-Specify the export format.  Acceptable arguments are @code{nar} and
-@code{docker}.  The default is the nar format.  When the format is
-@code{docker}, recursively export the specified store directory as a
-Docker image in tar archive format, as specified in
-@uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
-version 1.2.0 of the Docker Image Specification}.  Using
-@code{--format=docker} implies @code{--recursive}.  The generated
-archive can be loaded by Docker using @command{docker load}.
-
 @item --generate-key[=@var{parameters}]
 @cindex signing, archives
 Generate a new key pair for the daemon.  This is a prerequisite before