guix-devel/guix/scripts/environment.scm

285 lines
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Scheme

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2014, 2015 David Thompson <davet@gnu.org>
;;; Copyright © 2015 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 environment)
#:use-module (guix ui)
#:use-module (guix store)
#:use-module (guix derivations)
#:use-module (guix packages)
#:use-module (guix profiles)
#:use-module (guix search-paths)
#:use-module (guix utils)
#:use-module (guix monads)
#:use-module ((guix gexp) #:select (lower-inputs))
#:use-module (guix scripts build)
#:use-module (gnu packages)
#:use-module (ice-9 format)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-37)
#:use-module (srfi srfi-98)
#:export (guix-environment))
(define (evaluate-input-search-paths inputs search-paths)
"Evaluate SEARCH-PATHS, a list of search-path specifications, for the
directories corresponding to INPUTS, a list of (DERIVATION) or (DERIVATION
OUTPUT) tuples."
(let ((directories (map (match-lambda
(((? derivation? drv))
(derivation->output-path drv))
(((? derivation? drv) output)
(derivation->output-path drv output))
(((? string? item))
item))
inputs)))
(evaluate-search-paths search-paths directories)))
;; Protect some env vars from purification. Borrowed from nix-shell.
(define %precious-variables
'("HOME" "USER" "LOGNAME" "DISPLAY" "TERM" "TZ" "PAGER"))
(define (purify-environment)
"Unset almost all environment variables. A small number of variables such
as 'HOME' and 'USER' are left untouched."
(for-each unsetenv
(remove (cut member <> %precious-variables)
(match (get-environment-variables)
(((names . _) ...)
names)))))
(define (create-environment inputs paths pure?)
"Set the environment variables specified by PATHS for all the packages
within INPUTS. When PURE? is #t, unset the variables in the current
environment. Otherwise, augment existing enviroment variables with additional
search paths."
(when pure? (purify-environment))
(for-each (match-lambda
((($ <search-path-specification> variable _ separator) . value)
(let ((current (getenv variable)))
(setenv variable
(if (and current (not pure?))
(string-append value separator current)
value)))))
(evaluate-input-search-paths inputs paths))
;; Give users a way to know that they're in 'guix environment', so they can
;; adjust 'PS1' accordingly, for instance.
(setenv "GUIX_ENVIRONMENT" "t"))
(define (show-search-paths inputs search-paths pure?)
"Display SEARCH-PATHS applied to the packages specified by INPUTS, a list of
(DERIVATION) or (DERIVATION OUTPUT) tuples. When PURE? is #t, do not augment
existing environment variables with additional search paths."
(for-each (match-lambda
((search-path . value)
(display
(search-path-definition search-path value
#:kind (if pure? 'exact 'prefix)))
(newline)))
(evaluate-input-search-paths inputs search-paths)))
(define (package+propagated-inputs package output)
"Return the union of PACKAGE's OUTPUT and its transitive propagated inputs."
`((,(package-name package) ,package ,output)
,@(package-transitive-propagated-inputs package)))
(define (show-help)
(display (_ "Usage: guix environment [OPTION]... PACKAGE...
Build an environment that includes the dependencies of PACKAGE and execute a
shell command in that environment.\n"))
(display (_ "
-e, --expression=EXPR create environment for the package that EXPR
evaluates to"))
(display (_ "
-l, --load=FILE create environment for the package that the code within
FILE evaluates to"))
(display (_ "
-E, --exec=COMMAND execute COMMAND in new environment"))
(display (_ "
--ad-hoc include all specified packages in the environment instead
of only their inputs"))
(display (_ "
--pure unset existing environment variables"))
(display (_ "
--search-paths display needed environment variable definitions"))
(display (_ "
-s, --system=SYSTEM attempt to build for SYSTEM--e.g., \"i686-linux\""))
(newline)
(show-build-options-help)
(newline)
(display (_ "
-h, --help display this help and exit"))
(display (_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
(define %default-options
;; Default to opening a new shell.
`((exec . ,(or (getenv "SHELL") "/bin/sh"))
(system . ,(%current-system))
(substitutes? . #t)
(max-silent-time . 3600)
(verbosity . 0)))
(define %options
;; Specification of the command-line options.
(cons* (option '(#\h "help") #f #f
(lambda args
(show-help)
(exit 0)))
(option '(#\V "version") #f #f
(lambda args
(show-version-and-exit "guix environment")))
(option '("pure") #f #f
(lambda (opt name arg result)
(alist-cons 'pure #t result)))
(option '(#\E "exec") #t #f
(lambda (opt name arg result)
(alist-cons 'exec arg result)))
(option '("search-paths") #f #f
(lambda (opt name arg result)
(alist-cons 'search-paths #t result)))
(option '(#\l "load") #t #f
(lambda (opt name arg result)
(alist-cons 'load arg result)))
(option '(#\e "expression") #t #f
(lambda (opt name arg result)
(alist-cons 'expression arg result)))
(option '("ad-hoc") #f #f
(lambda (opt name arg result)
(alist-cons 'ad-hoc? #t result)))
(option '(#\n "dry-run") #f #f
(lambda (opt name arg result)
(alist-cons 'dry-run? #t result)))
(option '(#\s "system") #t #f
(lambda (opt name arg result)
(alist-cons 'system arg
(alist-delete 'system result eq?))))
%standard-build-options))
(define (pick-all alist key)
"Return a list of values in ALIST associated with KEY."
(define same-key? (cut eq? key <>))
(fold (lambda (pair memo)
(match pair
(((? same-key? k) . v)
(cons v memo))
(_ memo)))
'() alist))
(define (options/resolve-packages opts)
"Return OPTS with package specification strings replaced by actual
packages."
(append-map (match-lambda
(('package . (? string? spec))
(let-values (((package output)
(specification->package+output spec)))
`((package ,package ,output))))
(('expression . str)
;; Add all the outputs of the package STR evaluates to.
(match (read/eval str)
((? package? package)
(map (lambda (output)
`(package ,package ,output))
(package-outputs package)))))
(('load . file)
;; Add all the outputs of the package defined in FILE.
(let ((package (load* file (make-user-module '()))))
(map (lambda (output)
`(package ,package ,output))
(package-outputs package))))
(opt (list opt)))
opts))
(define (build-inputs inputs opts)
"Build the derivations in INPUTS, a list of (DERIVATION) or (DERIVATION
OUTPUT) tuples, using the build options in OPTS."
(let ((substitutes? (assoc-ref opts 'substitutes?))
(dry-run? (assoc-ref opts 'dry-run?)))
(match inputs
(((derivations _ ...) ...)
(mbegin %store-monad
(show-what-to-build* derivations
#:use-substitutes? substitutes?
#:dry-run? dry-run?)
(if dry-run?
(return #f)
(mbegin %store-monad
(set-build-options-from-command-line* opts)
(built-derivations derivations)
(return derivations))))))))
;; Entry point.
(define (guix-environment . args)
(define (handle-argument arg result)
(alist-cons 'package arg result))
(with-error-handling
(let* ((opts (parse-command-line args %options (list %default-options)
#:argument-handler handle-argument))
(pure? (assoc-ref opts 'pure))
(ad-hoc? (assoc-ref opts 'ad-hoc?))
(command (assoc-ref opts 'exec))
(packages (pick-all (options/resolve-packages opts) 'package))
(inputs (if ad-hoc?
(append-map (match-lambda
((package output)
(package+propagated-inputs package
output)))
packages)
(append-map (compose bag-transitive-inputs
package->bag
first)
packages)))
(paths (delete-duplicates
(cons $PATH
(append-map (match-lambda
((label (? package? p) _ ...)
(package-native-search-paths p))
(_
'()))
inputs))
eq?)))
(with-store store
(run-with-store store
(mlet %store-monad ((inputs (lower-inputs
(map (match-lambda
((label item)
(list item))
((label item output)
(list item output)))
inputs)
#:system (assoc-ref opts 'system))))
(mbegin %store-monad
;; First build INPUTS. This is necessary even for
;; --search-paths.
(build-inputs inputs opts)
(cond ((assoc-ref opts 'dry-run?)
(return #t))
((assoc-ref opts 'search-paths)
(show-search-paths inputs paths pure?)
(return #t))
(else
(create-environment inputs paths pure?)
(return (exit (status:exit-val (system command)))))))))))))