Add (guix inferior) and (guix scripts repl).

* guix/inferior.scm, guix/scripts/repl.scm, tests/inferior.scm: New
files.
* Makefile.am (MODULES): Add 'guix/scripts/repl.scm' and
'guix/inferior.scm'.
(SCM_TESTS): Add 'tests/inferior.scm'.
* doc/guix.texi (Invoking guix repl): New node.
This commit is contained in:
Ludovic Courtès 2018-07-10 14:18:36 +02:00
parent bc6e291ef0
commit 2ca299caf6
No known key found for this signature in database
GPG key ID: 090B11993D9AEBB5
5 changed files with 521 additions and 0 deletions

View file

@ -85,6 +85,7 @@ MODULES = \
guix/nar.scm \
guix/derivations.scm \
guix/grafts.scm \
guix/inferior.scm \
guix/gnu-maintenance.scm \
guix/self.scm \
guix/upstream.scm \
@ -200,6 +201,7 @@ MODULES = \
guix/scripts/substitute.scm \
guix/scripts/authenticate.scm \
guix/scripts/refresh.scm \
guix/scripts/repl.scm \
guix/scripts/system.scm \
guix/scripts/system/search.scm \
guix/scripts/lint.scm \
@ -357,6 +359,7 @@ SCM_TESTS = \
tests/profiles.scm \
tests/search-paths.scm \
tests/syscalls.scm \
tests/inferior.scm \
tests/gremlin.scm \
tests/bournish.scm \
tests/lint.scm \

View file

@ -166,6 +166,7 @@ Programming Interface
* Derivations:: Low-level interface to package derivations.
* The Store Monad:: Purely functional interface to the store.
* G-Expressions:: Manipulating build expressions.
* Invoking guix repl:: Fiddling with Guix interactively.
Defining Packages
@ -3267,6 +3268,7 @@ package definitions.
* Derivations:: Low-level interface to package derivations.
* The Store Monad:: Purely functional interface to the store.
* G-Expressions:: Manipulating build expressions.
* Invoking guix repl:: Fiddling with Guix interactively.
@end menu
@node Defining Packages
@ -5544,6 +5546,57 @@ corresponding to @var{obj} for @var{system}, cross-compiling for
has an associated gexp compiler, such as a @code{<package>}.
@end deffn
@node Invoking guix repl
@section Invoking @command{guix repl}
@cindex REPL, read-eval-print loop
The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
(REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
GNU Guile Reference Manual}). Compared to just launching the @command{guile}
command, @command{guix repl} guarantees that all the Guix modules and all its
dependencies are available in the search path. You can use it this way:
@example
$ guix repl
scheme@@(guile-user)> ,use (gnu packages base)
scheme@@(guile-user)> coreutils
$1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
@end example
@cindex inferiors
In addition, @command{guix repl} implements a simple machine-readable REPL
protocol for use by @code{(guix inferior)}, a facility to interact with
@dfn{inferiors}, separate processes running a potentially different revision
of Guix.
The available options are as follows:
@table @code
@item --type=@var{type}
@itemx -t @var{type}
Start a REPL of the given @var{TYPE}, which can be one of the following:
@table @code
@item guile
This is default, and it spawns a standard full-featured Guile REPL.
@item machine
Spawn a REPL that uses the machine-readable protocol. This is the protocol
that the @code{(guix inferior)} module speaks.
@end table
@item --listen=@var{endpoint}
By default, @command{guix repl} reads from standard input and writes to
standard output. When this option is passed, it will instead listen for
connections on @var{endpoint}. Here are examples of valid options:
@table @code
@item --listen=tcp:37146
Accept connections on localhost on port 37146.
@item --listen=unix:/tmp/socket
Accept connections on the Unix-domain socket @file{/tmp/socket}.
@end table
@end table
@c *********************************************************************
@node Utilities

197
guix/inferior.scm Normal file
View file

@ -0,0 +1,197 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix inferior)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-9 gnu)
#:use-module (ice-9 match)
#:use-module (ice-9 popen)
#:export (inferior?
open-inferior
close-inferior
inferior-eval
inferior-object?
inferior-package?
inferior-package-name
inferior-package-version
inferior-packages
inferior-package-synopsis
inferior-package-description))
;;; Commentary:
;;;
;;; This module provides a way to spawn Guix "inferior" processes and to talk
;;; to them. It allows us, from one instance of Guix, to interact with
;;; another instance of Guix coming from a different commit.
;;;
;;; Code:
;; Inferior Guix process.
(define-record-type <inferior>
(inferior pid socket version)
inferior?
(pid inferior-pid)
(socket inferior-socket)
(version inferior-version)) ;REPL protocol version
(define (inferior-pipe directory command)
"Return an input/output pipe on the Guix instance in DIRECTORY. This runs
'DIRECTORY/COMMAND repl' if it exists, or falls back to some other method if
it's an old Guix."
(let ((pipe (with-error-to-port (%make-void-port "w")
(lambda ()
(open-pipe* OPEN_BOTH
(string-append directory "/" command)
"repl" "-t" "machine")))))
(if (eof-object? (peek-char pipe))
(begin
(close-pipe pipe)
;; Older versions of Guix didn't have a 'guix repl' command, so
;; emulate it.
(open-pipe* OPEN_BOTH "guile"
"-L" (string-append directory "/share/guile/site/"
(effective-version))
"-C" (string-append directory "/share/guile/site/"
(effective-version))
"-C" (string-append directory "/lib/guile/"
(effective-version) "/site-ccache")
"-c"
(object->string
`(begin
(primitive-load ,(search-path %load-path
"guix/scripts/repl.scm"))
((@ (guix scripts repl) machine-repl))))))
pipe)))
(define* (open-inferior directory #:key (command "bin/guix"))
"Open the inferior Guix in DIRECTORY, running 'DIRECTORY/COMMAND repl' or
equivalent. Return #f if the inferior could not be launched."
(define pipe
(inferior-pipe directory command))
(setvbuf pipe _IOLBF)
(match (read pipe)
(('repl-version 0 rest ...)
(let ((result (inferior 'pipe pipe (cons 0 rest))))
(inferior-eval '(use-modules (guix)) result)
(inferior-eval '(use-modules (gnu)) result)
(inferior-eval '(define %package-table (make-hash-table))
result)
result))
(_
#f)))
(define (close-inferior inferior)
"Close INFERIOR."
(close-pipe (inferior-socket inferior)))
;; Non-self-quoting object of the inferior.
(define-record-type <inferior-object>
(inferior-object address appearance)
inferior-object?
(address inferior-object-address)
(appearance inferior-object-appearance))
(define (write-inferior-object object port)
(match object
(($ <inferior-object> _ appearance)
(format port "#<inferior-object ~a>" appearance))))
(set-record-type-printer! <inferior-object> write-inferior-object)
(define (inferior-eval exp inferior)
"Evaluate EXP in INFERIOR."
(define sexp->object
(match-lambda
(('value value)
value)
(('non-self-quoting address string)
(inferior-object address string))))
(write exp (inferior-socket inferior))
(newline (inferior-socket inferior))
(match (read (inferior-socket inferior))
(('values objects ...)
(apply values (map sexp->object objects)))
(('exception key objects ...)
(apply throw key (map sexp->object objects)))))
;;;
;;; Inferior packages.
;;;
(define-record-type <inferior-package>
(inferior-package inferior name version id)
inferior-package?
(inferior inferior-package-inferior)
(name inferior-package-name)
(version inferior-package-version)
(id inferior-package-id))
(define (write-inferior-package package port)
(match package
(($ <inferior-package> _ name version)
(format port "#<inferior-package ~a@~a ~a>"
name version
(number->string (object-address package) 16)))))
(set-record-type-printer! <inferior-package> write-inferior-package)
(define (inferior-packages inferior)
"Return the list of packages known to INFERIOR."
(let ((result (inferior-eval
'(fold-packages (lambda (package result)
(let ((id (object-address package)))
(hashv-set! %package-table id package)
(cons (list (package-name package)
(package-version package)
id)
result)))
'())
inferior)))
(map (match-lambda
((name version id)
(inferior-package inferior name version id)))
result)))
(define (inferior-package-field package getter)
"Return the field of PACKAGE, an inferior package, accessed with GETTER."
(let ((inferior (inferior-package-inferior package))
(id (inferior-package-id package)))
(inferior-eval `(,getter (hashv-ref %package-table ,id))
inferior)))
(define* (inferior-package-synopsis package #:key (translate? #t))
"Return the Texinfo synopsis of PACKAGE, an inferior package. When
TRANSLATE? is true, translate it to the current locale's language."
(inferior-package-field package
(if translate?
'(compose (@ (guix ui) P_) package-synopsis)
'package-synopsis)))
(define* (inferior-package-description package #:key (translate? #t))
"Return the Texinfo description of PACKAGE, an inferior package. When
TRANSLATE? is true, translate it to the current locale's language."
(inferior-package-field package
(if translate?
'(compose (@ (guix ui) P_) package-description)
'package-description)))

199
guix/scripts/repl.scm Normal file
View file

@ -0,0 +1,199 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix scripts repl)
#:use-module (guix ui)
#:use-module (guix scripts)
#:use-module (guix utils)
#:use-module (guix packages)
#:use-module (gnu packages)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-37)
#:use-module (ice-9 match)
#:use-module (rnrs bytevectors)
#:autoload (system repl repl) (start-repl)
#:autoload (system repl server)
(make-tcp-server-socket make-unix-domain-server-socket)
#:export (machine-repl
guix-repl))
;;; Commentary:
;;;
;;; This command provides a Guile REPL
(define %default-options
`((type . guile)))
(define %options
(list (option '(#\h "help") #f #f
(lambda args
(show-help)
(exit 0)))
(option '(#\V "version") #f #f
(lambda args
(show-version-and-exit "guix repl")))
(option '(#\t "type") #t #f
(lambda (opt name arg result)
(alist-cons 'type (string->symbol arg) result)))
(option '("listen") #t #f
(lambda (opt name arg result)
(alist-cons 'listen arg result)))))
(define (show-help)
(display (G_ "Usage: guix repl [OPTIONS...]
Start a Guile REPL in the Guix execution environment.\n"))
(display (G_ "
-t, --type=TYPE start a REPL of the given TYPE"))
(newline)
(display (G_ "
-h, --help display this help and exit"))
(display (G_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
(define (self-quoting? x)
"Return #t if X is self-quoting."
(letrec-syntax ((one-of (syntax-rules ()
((_) #f)
((_ pred rest ...)
(or (pred x)
(one-of rest ...))))))
(one-of symbol? string? pair? null? vector?
bytevector? number? boolean?)))
(define user-module
;; Module where we execute user code.
(let ((module (resolve-module '(guix-user) #f #f #:ensure #t)))
(beautify-user-module! module)
module))
(define* (machine-repl #:optional
(input (current-input-port))
(output (current-output-port)))
"Run a machine-usable REPL over ports INPUT and OUTPUT.
The protocol of this REPL is meant to be machine-readable and provides proper
support to represent multiple-value returns, exceptions, objects that lack a
read syntax, and so on. As such it is more convenient and robust than parsing
Guile's REPL prompt."
(define (value->sexp value)
(if (self-quoting? value)
`(value ,value)
`(non-self-quoting ,(object-address value)
,(object->string value))))
(write `(repl-version 0 0) output)
(newline output)
(force-output output)
(let loop ()
(match (read input)
((? eof-object?) #t)
(exp
(catch #t
(lambda ()
(let ((results (call-with-values
(lambda ()
(primitive-eval exp))
list)))
(write `(values ,@(map value->sexp results))
output)
(newline output)
(force-output output)))
(lambda (key . args)
(write `(exception ,key ,@(map value->sexp args)))
(newline output)
(force-output output)))
(loop)))))
(define (call-with-connection spec thunk)
"Dynamically-bind the current input and output ports according to SPEC and
call THUNK."
(if (not spec)
(thunk)
;; Note: the "PROTO:" prefix in SPEC is here so that we can eventually
;; parse things like "fd:123" in a non-ambiguous way.
(match (string-index spec #\:)
(#f
(leave (G_ "~A: invalid listen specification~%") spec))
(index
(let ((protocol (string-take spec index))
(address (string-drop spec (+ index 1))))
(define socket
(match protocol
("tcp"
(make-tcp-server-socket #:port (string->number address)))
("unix"
(make-unix-domain-server-socket #:path address))
(_
(leave (G_ "~A: unsupported protocol family~%")
protocol))))
(listen socket 10)
(let loop ()
(match (accept socket)
((connection . address)
(if (= AF_UNIX (sockaddr:fam address))
(info (G_ "accepted connection~%"))
(info (G_ "accepted connection from ~a~%")
(inet-ntop (sockaddr:fam address)
(sockaddr:addr address))))
(dynamic-wind
(const #t)
(lambda ()
(parameterize ((current-input-port connection)
(current-output-port connection))
(thunk)))
(lambda ()
(false-if-exception (close-port connection))
(info (G_ "connection closed~%"))))))
(loop)))))))
(define (guix-repl . args)
(define opts
;; Return the list of package names.
(args-fold* args %options
(lambda (opt name arg result)
(leave (G_ "~A: unrecognized option~%") name))
(lambda (arg result)
(leave (G_ "~A: extraneous argument~%") arg))
%default-options))
(with-error-handling
(let ((type (assoc-ref opts 'type)))
(call-with-connection (assoc-ref opts 'listen)
(lambda ()
(case type
((guile)
(save-module-excursion
(lambda ()
(set-current-module user-module)
(start-repl))))
((machine)
(machine-repl))
(else
(leave (G_ "~a: unknown type of REPL~%") type))))))))
;; Local Variables:
;; eval: (put 'call-with-connection 'scheme-indent-function 1)
;; End:

69
tests/inferior.scm Normal file
View file

@ -0,0 +1,69 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (test-inferior)
#:use-module (guix inferior)
#:use-module (guix packages)
#:use-module (gnu packages)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-64))
(define %top-srcdir
(dirname (search-path %load-path "guix.scm")))
(define %top-builddir
(dirname (search-path %load-compiled-path "guix.go")))
(test-begin "inferior")
(test-equal "open-inferior"
'(42 #t)
(let ((inferior (open-inferior %top-builddir
#:command "scripts/guix")))
(and (inferior? inferior)
(let ((a (inferior-eval '(apply * '(6 7)) inferior))
(b (inferior-eval '(@ (gnu packages base) coreutils)
inferior)))
(close-inferior inferior)
(list a (inferior-object? b))))))
(test-equal "inferior-packages"
(take (sort (fold-packages (lambda (package lst)
(alist-cons (package-name package)
(package-version package)
lst))
'())
(lambda (x y)
(string<? (car x) (car y))))
10)
(let* ((inferior (open-inferior %top-builddir
#:command "scripts/guix"))
(packages (inferior-packages inferior)))
(and (every string? (map inferior-package-synopsis packages))
(begin
(close-inferior inferior)
(take (sort (map (lambda (package)
(cons (inferior-package-name package)
(inferior-package-version package)))
packages)
(lambda (x y)
(string<? (car x) (car y))))
10)))))
(test-end "inferior")