unofficial mirror of bug-guix@gnu.org 
 help / color / mirror / code / Atom feed
blob ad2442f50eeada7ac29c239c7a349376255c8f94 45375 bytes (raw)
name: guix/channels.scm 	 # note: path name is non-authoritative(*)

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
 
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2018 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2019 Jan (janneke) Nieuwenhuizen <janneke@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 channels)
  #:use-module (git)
  #:use-module (guix git)
  #:use-module (guix git-authenticate)
  #:use-module ((guix openpgp)
                #:select (openpgp-public-key-fingerprint
                          openpgp-format-fingerprint))
  #:use-module (guix base16)
  #:use-module (guix records)
  #:use-module (guix gexp)
  #:use-module (guix modules)
  #:use-module (guix discovery)
  #:use-module (guix monads)
  #:use-module (guix profiles)
  #:use-module (guix packages)
  #:use-module (guix progress)
  #:use-module (guix derivations)
  #:use-module (guix combinators)
  #:use-module (guix diagnostics)
  #:use-module (guix sets)
  #:use-module (guix store)
  #:use-module (guix i18n)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-2)
  #:use-module (srfi srfi-9)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:autoload   (guix self) (whole-package make-config.scm)
  #:autoload   (guix inferior) (gexp->derivation-in-inferior) ;FIXME: circular dep
  #:autoload   (guix quirks) (%quirks %patches applicable-patch? apply-patch)
  #:use-module (ice-9 format)
  #:use-module (ice-9 match)
  #:use-module (ice-9 vlist)
  #:use-module ((ice-9 rdelim) #:select (read-string))
  #:use-module ((rnrs bytevectors) #:select (bytevector=?))
  #:export (channel
            channel?
            channel-name
            channel-url
            channel-branch
            channel-commit
            channel-introduction
            channel-location

            channel-introduction?
            make-channel-introduction
            channel-introduction-first-signed-commit
            channel-introduction-first-commit-signer

            openpgp-fingerprint->bytevector
            openpgp-fingerprint

            %default-channels
            guix-channel?

            channel-instance?
            channel-instance-channel
            channel-instance-commit
            channel-instance-checkout

            authenticate-channel
            latest-channel-instances
            checkout->channel-instance
            latest-channel-derivation
            channel-instances->manifest
            %channel-profile-hooks
            channel-instances->derivation
            ensure-forward-channel-update

            profile-channels

            channel-news-entry?
            channel-news-entry-commit
            channel-news-entry-tag
            channel-news-entry-title
            channel-news-entry-body

            channel-news-for-commit))

;;; Commentary:
;;;
;;; This module implements "channels."  A channel is usually a source of
;;; package definitions.  There's a special channel, the 'guix' channel, that
;;; provides all of Guix, including its commands and its documentation.
;;; User-defined channels are expected to typically provide a bunch of .scm
;;; files meant to be added to the '%package-search-path'.
;;;
;;; This module provides tools to fetch and update channels from a Git
;;; repository and to build them.
;;;
;;; Code:

(define-record-type* <channel> channel make-channel
  channel?
  (name      channel-name)
  (url       channel-url)
  (branch    channel-branch (default "master"))
  (commit    channel-commit (default #f))
  (introduction channel-introduction (default #f))
  (location  channel-location
             (default (current-source-location)) (innate)))

;; Channel introductions.  A "channel introduction" provides a commit/signer
;; pair that specifies the first commit of the authentication process as well
;; as its signer's fingerprint.  Introductions are used to bootstrap trust in
;; a channel.
(define-record-type <channel-introduction>
  (%make-channel-introduction first-signed-commit first-commit-signer)
  channel-introduction?
  (first-signed-commit  channel-introduction-first-signed-commit)  ;hex string
  (first-commit-signer  channel-introduction-first-commit-signer)) ;bytevector

(define (make-channel-introduction commit signer)
  "Return a new channel introduction: COMMIT is the introductory where
authentication starts, and SIGNER is the OpenPGP fingerprint (a bytevector) of
the signer of that commit."
  (%make-channel-introduction commit signer))

(define (openpgp-fingerprint->bytevector str)
  "Convert STR, an OpenPGP fingerprint (hexadecimal string with whitespace),
to the corresponding bytevector."
  (base16-string->bytevector
   (string-downcase (string-filter char-set:hex-digit str))))

(define-syntax openpgp-fingerprint
  (lambda (s)
    "Convert STR, an OpenPGP fingerprint (hexadecimal string with whitespace),
to the corresponding bytevector."
    (syntax-case s ()
      ((_ str)
       (string? (syntax->datum #'str))
       (openpgp-fingerprint->bytevector (syntax->datum #'str)))
      ((_ str)
       #'(openpgp-fingerprint->bytevector str)))))

(define %guix-channel-introduction
  ;; Introduction of the official 'guix channel.  The chosen commit is the
  ;; first one that introduces '.guix-authorizations' on the 'staging'
  ;; branch that was eventually merged in 'master'.  Any branch starting
  ;; before that commit cannot be merged or it will be rejected by 'guix pull'
  ;; & co.
  (make-channel-introduction
   "9edb3f66fd807b096b48283debdcddccfea34bad"     ;2020-05-26
   (openpgp-fingerprint                           ;mbakke
    "BBB0 2DDF 2CEA F6A8 0D1D  E643 A2A0 6DF2 A33A 54FA")))

(define %default-channel-url
  ;; URL of the default 'guix' channel.
  "https://git.savannah.gnu.org/git/guix.git")

(define %default-channels
  ;; Default list of channels.
  (list (channel
         (name 'guix)
         (branch "master")
         (url %default-channel-url)
         (introduction %guix-channel-introduction))))

(define (guix-channel? channel)
  "Return true if CHANNEL is the 'guix' channel."
  (eq? 'guix (channel-name channel)))

(define (ensure-default-introduction chan)
  "If CHAN represents the \"official\" 'guix' channel and lacks an
introduction, add it."
  (if (and (guix-channel? chan)
           (not (channel-introduction chan))
           (string=? (channel-url chan) %default-channel-url))
      (channel (inherit chan)
               (introduction %guix-channel-introduction))
      chan))

(define-record-type <channel-instance>
  (channel-instance channel commit checkout)
  channel-instance?
  (channel   channel-instance-channel)
  (commit    channel-instance-commit)
  (checkout  channel-instance-checkout))

(define-record-type <channel-metadata>
  (channel-metadata directory dependencies news-file keyring-reference url)
  channel-metadata?
  (directory     channel-metadata-directory)      ;string with leading slash
  (dependencies  channel-metadata-dependencies)   ;list of <channel>
  (news-file     channel-metadata-news-file)      ;string | #f
  (keyring-reference channel-metadata-keyring-reference) ;string
  (url           channel-metadata-url))           ;string | #f

(define %default-keyring-reference
  ;; Default value of the 'keyring-reference' field.
  "keyring")

(define (channel-reference channel)
  "Return the \"reference\" for CHANNEL, an sexp suitable for
'latest-repository-commit'."
  (match (channel-commit channel)
    (#f      `(branch . ,(channel-branch channel)))
    (commit  `(commit . ,(channel-commit channel)))))

(define sexp->channel-introduction
  (match-lambda
    (('channel-introduction ('version 0)
                            ('commit commit) ('signer signer)
                            _ ...)
     (make-channel-introduction commit (openpgp-fingerprint signer)))
    (x #f)))

(define (read-channel-metadata port)
  "Read from PORT channel metadata in the format expected for the
'.guix-channel' file.  Return a <channel-metadata> record, or raise an error
if valid metadata could not be read from PORT."
  (match (read port)
    (('channel ('version 0) properties ...)
     (let ((directory    (and=> (assoc-ref properties 'directory) first))
           (dependencies (or (assoc-ref properties 'dependencies) '()))
           (news-file    (and=> (assoc-ref properties 'news-file) first))
           (url          (and=> (assoc-ref properties 'url) first))
           (keyring-reference
            (or (and=> (assoc-ref properties 'keyring-reference) first)
                %default-keyring-reference)))
       (channel-metadata
        (cond ((not directory) "/")               ;directory
              ((string-prefix? "/" directory) directory)
              (else (string-append "/" directory)))
        (map (lambda (item)                       ;dependencies
               (let ((get (lambda* (key #:optional default)
                            (or (and=> (assoc-ref item key) first) default))))
                 (and-let* ((name (get 'name))
                            (url (get 'url))
                            (branch (get 'branch "master")))
                   (channel
                    (name name)
                    (branch branch)
                    (url url)
                    (commit (get 'commit))
                    (introduction (and=> (get 'introduction)
                                         sexp->channel-introduction))))))
             dependencies)
        news-file
        keyring-reference
        url)))
    ((and ('channel ('version version) _ ...) sexp)
     (raise (condition
             (&message (message "unsupported '.guix-channel' version"))
             (&error-location
              (location (source-properties->location
                         (source-properties sexp)))))))
    (sexp
     (raise (condition
             (&message (message "invalid '.guix-channel' file"))
             (&error-location
              (location (source-properties->location
                         (source-properties sexp)))))))))

(define (read-channel-metadata-from-source source)
  "Return a channel-metadata record read from channel's SOURCE/.guix-channel
description file, or return the default channel-metadata record if that file
doesn't exist."
  (catch 'system-error
    (lambda ()
      (call-with-input-file (string-append source "/.guix-channel")
        read-channel-metadata))
    (lambda args
      (if (= ENOENT (system-error-errno args))
          (channel-metadata "/" '() #f %default-keyring-reference #f)
          (apply throw args)))))

(define (channel-instance-metadata instance)
  "Return a channel-metadata record read from the channel INSTANCE's
description file or its default value."
  (read-channel-metadata-from-source (channel-instance-checkout instance)))

(define (channel-instance-dependencies instance)
  "Return the list of channels that are declared as dependencies for the given
channel INSTANCE."
  (channel-metadata-dependencies (channel-instance-metadata instance)))

(define (apply-patches checkout commit patches)
  "Apply the matching PATCHES to CHECKOUT, modifying files in place.  The
result is unspecified."
  (let loop ((patches patches))
    (match patches
      (() #t)
      ((patch rest ...)
       (when (applicable-patch? patch checkout commit)
         (apply-patch patch checkout))
       (loop rest)))))

(define commit-short-id
  (compose (cut string-take <> 7) oid->string commit-id))

(define* (authenticate-channel channel checkout commit
                               #:key (keyring-reference-prefix "origin/"))
  "Authenticate the given COMMIT of CHANNEL, available at CHECKOUT, a
directory containing a CHANNEL checkout.  Raise an error if authentication
fails."
  (define intro
    (channel-introduction channel))

  (define cache-key
    (string-append "channels/" (symbol->string (channel-name channel))))

  (define keyring-reference
    (channel-metadata-keyring-reference
     (read-channel-metadata-from-source checkout)))

  (define (make-reporter start-commit end-commit commits)
    (format (current-error-port)
            (G_ "Authenticating channel '~a', commits ~a to ~a (~h new \
commits)...~%")
            (channel-name channel)
            (commit-short-id start-commit)
            (commit-short-id end-commit)
            (length commits))

    (progress-reporter/bar (length commits)))

  ;; XXX: Too bad we need to re-open CHECKOUT.
  (with-repository checkout repository
    (authenticate-repository repository
                             (string->oid
                              (channel-introduction-first-signed-commit intro))
                             (channel-introduction-first-commit-signer intro)
                             #:end (string->oid commit)
                             #:keyring-reference
                             (string-append keyring-reference-prefix
                                            keyring-reference)
                             #:make-reporter make-reporter
                             #:cache-key cache-key)))

(define* (latest-channel-instance store channel
                                  #:key (patches %patches)
                                  starting-commit
                                  (authenticate? #f)
                                  (validate-pull
                                   ensure-forward-channel-update))
  "Return the latest channel instance for CHANNEL.  When STARTING-COMMIT is
true, call VALIDATE-PULL with CHANNEL, STARTING-COMMIT, the target commit, and
their relation.  When AUTHENTICATE? is false, CHANNEL is not authenticated."
  (define (dot-git? file stat)
    (and (string=? (basename file) ".git")
         (eq? 'directory (stat:type stat))))

  (let-values (((channel)
                (ensure-default-introduction channel))
               ((checkout commit relation)
                (update-cached-checkout (channel-url channel)
                                        #:ref (channel-reference channel)
                                        #:starting-commit starting-commit)))
    (when relation
      (validate-pull channel starting-commit commit relation))

    (if authenticate?
        (if (channel-introduction channel)
            (authenticate-channel channel checkout commit)
            ;; TODO: Warn for all the channels once the authentication interface
            ;; is public.
            (when (guix-channel? channel)
              (raise (make-compound-condition
                      (formatted-message (G_ "channel '~a' lacks an \
introduction and cannot be authenticated~%")
                                         (channel-name channel))
                      (condition
                       (&fix-hint
                        (hint (G_ "Add the missing introduction to your
channels file to address the issue.  Alternatively, you can pass
@option{--disable-authentication}, at the risk of running unauthenticated and
thus potentially malicious code."))))))))
        (warning (G_ "channel authentication disabled~%")))

    (when (guix-channel? channel)
      ;; Apply the relevant subset of PATCHES directly in CHECKOUT.  This is
      ;; safe to do because 'switch-to-ref' eventually does a hard reset.
      (apply-patches checkout commit patches))

    (let* ((name     (url+commit->name (channel-url channel) commit))
           (checkout (add-to-store store name #t "sha256" checkout
                                   #:select? (negate dot-git?))))
      (channel-instance channel commit checkout))))

(define (ensure-forward-channel-update channel start commit relation)
  "Raise an error if RELATION is not 'ancestor, meaning that START is not an
ancestor of COMMIT, unless CHANNEL specifies a commit.

This procedure implements a channel update policy meant to be used as a
#:validate-pull argument."
  (match relation
    ('ancestor #t)
    ('self #t)
    (_
     (raise (make-compound-condition
             (condition
              (&message (message
                         (format #f (G_ "\
aborting update of channel '~a' to commit ~a, which is not a descendant of ~a")
                                 (channel-name channel)
                                 commit start))))

             ;; If the user asked for a specific commit, they might want
             ;; that to happen nevertheless, so tell them about the
             ;; relevant 'guix pull' option.
             (if (channel-commit channel)
                 (condition
                  (&fix-hint
                   (hint (G_ "Use @option{--allow-downgrades} to force
this downgrade."))))
                 (condition
                  (&fix-hint
                   (hint (G_ "This could indicate that the channel has
been tampered with and is trying to force a roll-back, preventing you from
getting the latest updates.  If you think this is not the case, explicitly
allow non-forward updates."))))))))))

(define (channel-instance-primary-url instance)
  "Return the primary URL advertised for INSTANCE, or #f if there is no such
information."
  (channel-metadata-url (channel-instance-metadata instance)))

(define* (latest-channel-instances store channels
                                   #:key
                                   (current-channels '())
                                   (authenticate? #t)
                                   (validate-pull
                                    ensure-forward-channel-update))
  "Return a list of channel instances corresponding to the latest checkouts of
CHANNELS and the channels on which they depend.

When AUTHENTICATE? is true, authenticate the subset of CHANNELS that has a
\"channel introduction\".

CURRENT-CHANNELS is the list of currently used channels.  It is compared
against the newly-fetched instances of CHANNELS, and VALIDATE-PULL is called
for each channel update and can choose to emit warnings or raise an error,
depending on the policy it implements."
  ;; Only process channels that are unique, or that are more specific than a
  ;; previous channel specification.
  (define (ignore? channel others)
    (member channel others
            (lambda (a b)
              (and (eq? (channel-name a) (channel-name b))
                   (or (channel-commit b)
                       (not (or (channel-commit a)
                                (channel-commit b))))))))

  (define (current-commit name)
    ;; Return the current commit for channel NAME.
    (any (lambda (channel)
           (and (eq? (channel-name channel) name)
                (channel-commit channel)))
         current-channels))

  (let loop ((channels channels)
             (previous-channels '()))
    ;; Accumulate a list of instances.  A list of processed channels is also
    ;; accumulated to decide on duplicate channel specifications.
    (define-values (resulting-channels instances)
      (fold2 (lambda (channel previous-channels instances)
               (if (ignore? channel previous-channels)
                   (values previous-channels instances)
                   (begin
                     (format (current-error-port)
                             (G_ "Updating channel '~a' from Git repository at '~a'...~%")
                             (channel-name channel)
                             (channel-url channel))
                     (let* ((current (current-commit (channel-name channel)))
                            (instance
                             (latest-channel-instance store channel
                                                      #:authenticate?
                                                      authenticate?
                                                      #:validate-pull
                                                      validate-pull
                                                      #:starting-commit
                                                      current)))
                       (when authenticate?
                         ;; CHANNEL is authenticated so we can trust the
                         ;; primary URL advertised in its metadata and warn
                         ;; about possibly stale mirrors.
                         (let ((primary-url (channel-instance-primary-url
                                             instance)))
                           (unless (or (not primary-url)
                                       (channel-commit channel)
                                       (string=? primary-url (channel-url channel)))
                             (warning (G_ "pulled channel '~a' from a mirror \
of ~a, which might be stale~%")
                                      (channel-name channel)
                                      primary-url))))

                       (let-values (((new-instances new-channels)
                                     (loop (channel-instance-dependencies instance)
                                           previous-channels)))
                         (values (append (cons channel new-channels)
                                         previous-channels)
                                 (append (cons instance new-instances)
                                         instances)))))))
             previous-channels
             '()                                  ;instances
             channels))

    (let ((instance-name (compose channel-name channel-instance-channel)))
      ;; Remove all earlier channel specifications if they are followed by a
      ;; more specific one.
      (values (delete-duplicates instances
                                 (lambda (a b)
                                   (eq? (instance-name a) (instance-name b))))
              resulting-channels))))

(define* (checkout->channel-instance checkout
                                     #:key commit
                                     (url checkout) (name 'guix))
  "Return a channel instance for CHECKOUT, which is assumed to be a checkout
of COMMIT at URL.  Use NAME as the channel name."
  (let* ((commit  (or commit (make-string 40 #\0)))
         (channel (channel (name name)
                           (commit commit)
                           (url url))))
    (channel-instance channel commit checkout)))

(define %self-build-file
  ;; The file containing code to build Guix.  This serves the same purpose as
  ;; a makefile, and, similarly, is intended to always keep this name.
  "build-aux/build-self.scm")

(define %pull-version
  ;; This is the version of the 'guix pull' protocol.  It specifies what's
  ;; expected from %SELF-BUILD-FILE.  The initial version ("0") was when we'd
  ;; place a set of compiled Guile modules in ~/.config/guix/latest.
  1)

(define (standard-module-derivation name source core dependencies)
  "Return a derivation that builds with CORE, a Guix instance, the Scheme
modules in SOURCE and that depend on DEPENDENCIES, a list of lowerable
objects.  The assumption is that SOURCE contains package modules to be added
to '%package-module-path'."

  (let* ((metadata (read-channel-metadata-from-source source))
         (directory (channel-metadata-directory metadata)))

    (define build
      ;; This is code that we'll run in CORE, a Guix instance, with its own
      ;; modules and so on.  That way, we make sure these modules are built for
      ;; the right Guile version, with the right dependencies, and that they get
      ;; to see the right (gnu packages …) modules.
      (with-extensions dependencies
        #~(begin
            (use-modules (guix build compile)
                         (guix build utils)
                         (srfi srfi-26))

            (define go
              (string-append #$output "/lib/guile/" (effective-version)
                             "/site-ccache"))
            (define scm
              (string-append #$output "/share/guile/site/"
                             (effective-version)))

            (let* ((subdir #$directory)
                   (source (string-append #$source subdir)))
              (compile-files source go (find-files source "\\.scm$"))
              (mkdir-p (dirname scm))
              (symlink (string-append #$source subdir) scm))

            scm)))

    (gexp->derivation-in-inferior name build core)))

(define* (guile-for-source source #:optional (quirks %quirks))
  "Return the Guile package to use when building SOURCE or #f if the default
'%guile-for-build' should be good enough."
  (let loop ((quirks quirks))
    (match quirks
      (()
       #f)
      (((predicate . guile) rest ...)
       (if (predicate source) (guile) (loop rest))))))

(define (call-with-guile guile thunk)
  (lambda (store)
    (values (parameterize ((%guile-for-build
                            (if guile
                                (package-derivation store guile)
                                (%guile-for-build))))
              (run-with-store store (thunk)))
            store)))

(define-syntax-rule (with-guile guile exp ...)
  "Set GUILE as the '%guile-for-build' parameter for the dynamic extent of
EXP, a series of monadic expressions."
  (call-with-guile guile (lambda ()
                           (mbegin %store-monad exp ...))))

(define (with-trivial-build-handler mvalue)
  "Run MVALUE, a monadic value, with a \"trivial\" build handler installed
that unconditionally resumes the continuation."
  (lambda (store)
    (with-build-handler (lambda (continue . _)
                          (continue #t))
      (values (run-with-store store mvalue)
              store))))

(define* (build-from-source name source
                            #:key core verbose? commit
                            (dependencies '()))
  "Return a derivation to build Guix from SOURCE, using the self-build script
contained therein; use COMMIT as the version string.  When CORE is true, build
package modules under SOURCE using CORE, an instance of Guix."
  ;; Running the self-build script makes it easier to update the build
  ;; procedure: the self-build script of the Guix-to-be-installed contains the
  ;; right dependencies, build procedure, etc., which the Guix-in-use may not
  ;; be know.
  (define script
    (string-append source "/" %self-build-file))

  (if (file-exists? script)
      (let ((build (save-module-excursion
                    (lambda ()
                      ;; Disable deprecation warnings; it's OK for SCRIPT to
                      ;; use deprecated APIs and the user doesn't have to know
                      ;; about it.
                      (parameterize ((guix-warning-port
                                      (%make-void-port "w")))
                        (primitive-load script)))))
            (guile (guile-for-source source)))
        ;; BUILD must be a monadic procedure of at least one argument: the
        ;; source tree.
        ;;
        ;; Note: BUILD can return #f if it does not support %PULL-VERSION.  In
        ;; the future we'll fall back to a previous version of the protocol
        ;; when that happens.
        (with-guile guile
          ;; BUILD is usually quite costly.  Install a "trivial" build handler
          ;; so we don't bounce an outer build-accumulator handler that could
          ;; cause us to redo half of the BUILD computation several times just
          ;; to realize it gives the same result.
          (with-trivial-build-handler
           (build source #:verbose? verbose? #:version commit
                  #:pull-version %pull-version))))

      ;; Build a set of modules that extend Guix using the standard method.
      (standard-module-derivation name source core dependencies)))

(define* (build-channel-instance instance
                                 #:optional core (dependencies '()))
  "Return, as a monadic value, the derivation for INSTANCE, a channel
instance.  DEPENDENCIES is a list of extensions providing Guile modules that
INSTANCE depends on."
  (build-from-source (symbol->string
                      (channel-name (channel-instance-channel instance)))
                     (channel-instance-checkout instance)
                     #:commit (channel-instance-commit instance)
                     #:core core
                     #:dependencies dependencies))

(define (resolve-dependencies instances)
  "Return a procedure that, given one of the elements of INSTANCES, returns
list of instances it depends on."
  (define channel-instance-name
    (compose channel-name channel-instance-channel))

  (define table                                   ;map a name to an instance
    (fold (lambda (instance table)
            (vhash-consq (channel-instance-name instance)
                         instance table))
          vlist-null
          instances))

  (define edges
    (fold (lambda (instance edges)
            (fold (lambda (channel edges)
                    (let ((name (channel-name channel)))
                      (match (vhash-assq name table)
                        ((_ . target)
                         (vhash-consq instance target edges)))))
                  edges
                  (channel-instance-dependencies instance)))
          vlist-null
          instances))

  (lambda (instance)
    (vhash-foldq* cons '() instance edges)))

(define (channel-instance-derivations instances)
  "Return the list of derivations to build INSTANCES, in the same order as
INSTANCES."
  (define core-instance
    ;; The 'guix' channel is treated specially: it's an implicit dependency of
    ;; all the other channels.
    (find (lambda (instance)
            (guix-channel? (channel-instance-channel instance)))
          instances))

  (define edges
    (resolve-dependencies instances))

  (define (instance->derivation instance)
    (mlet %store-monad ((system (current-system)))
      (mcached (if (eq? instance core-instance)
                   (build-channel-instance instance)
                   (mlet %store-monad ((core (instance->derivation core-instance))
                                       (deps (mapm %store-monad instance->derivation
                                                   (edges instance))))
                     (build-channel-instance instance core deps)))
               instance
               system)))

  (unless core-instance
    (let ((loc (and=> (any (compose channel-location channel-instance-channel)
                           instances)
                      source-properties->location)))
      (raise (apply make-compound-condition
                    (condition
                     (&message (message "'guix' channel is lacking")))
                    (condition
                     (&fix-hint (hint (G_ "Make sure your list of channels
contains one channel named @code{guix} providing the core of Guix."))))
                    (if loc
                        (list (condition (&error-location (location loc))))
                        '())))))

  (mapm %store-monad instance->derivation instances))

(define (whole-package-for-legacy name modules)
  "Return a full-blown Guix package for MODULES, a derivation that builds Guix
modules in the old ~/.config/guix/latest style."
  (define packages
    (resolve-interface '(gnu packages guile)))

  (define modules+compiled
    ;; Since MODULES contains both .scm and .go files at its root, re-bundle
    ;; it so that it has share/guile/site and lib/guile, which is what
    ;; 'whole-package' expects.
    (computed-file (derivation-name modules)
                   (with-imported-modules '((guix build utils))
                     #~(begin
                         (use-modules (guix build utils))

                         (define version
                           (effective-version))
                         (define share
                           (string-append #$output "/share/guile/site"))
                         (define lib
                           (string-append #$output "/lib/guile/" version))

                         (mkdir-p share) (mkdir-p lib)
                         (symlink #$modules (string-append share "/" version))
                         (symlink #$modules (string-append lib "/site-ccache"))))))

  (letrec-syntax ((list (syntax-rules (->)
                          ((_)
                           '())
                          ((_ (module -> variable) rest ...)
                           (cons (module-ref (resolve-interface
                                              '(gnu packages module))
                                             'variable)
                                 (list rest ...)))
                          ((_ variable rest ...)
                           (cons (module-ref packages 'variable)
                                 (list rest ...))))))
    (whole-package name modules+compiled

                   ;; In the "old style", %SELF-BUILD-FILE would simply return a
                   ;; derivation that builds modules.  We have to infer what the
                   ;; dependencies of these modules were.
                   (list guile-json-3 guile-git guile-bytestructures
                         (ssh -> guile-ssh) (tls -> gnutls)))))

(define (old-style-guix? drv)
  "Return true if DRV corresponds to a ~/.config/guix/latest style of
derivation."
  ;; Here we rely on a gross historical fact: that derivations produced by the
  ;; "old style" (before commit 8a0d9bc8a3f153159d9e239a151c0fa98f1e12d8,
  ;; dated May 30, 2018) did not depend on "guix-command.drv".
  (not (find (lambda (input)
               (string=? "guix-command"
                         (derivation-name
                          (derivation-input-derivation input))))
             (derivation-inputs drv))))

(define (channel-instances->manifest instances)
  "Return a profile manifest with entries for all of INSTANCES, a list of
channel instances."
  (define (instance->entry instance drv)
    (let* ((commit  (channel-instance-commit instance))
           (channel (channel-instance-channel instance))
           (intro   (channel-introduction channel)))
      (manifest-entry
        (name (symbol->string (channel-name channel)))
        (version (string-take commit 7))
        (item (if (guix-channel? channel)
                  (if (old-style-guix? drv)
                      (whole-package-for-legacy (string-append name "-" version)
                                                drv)
                      drv)
                  drv))
        (properties
         `((source (repository
                    (version 0)
                    (url ,(channel-url channel))
                    (branch ,(channel-branch channel))
                    (commit ,commit)
                    ,@(if intro
                          `((introduction
                             (channel-introduction
                              (version 0)
                              (commit
                               ,(channel-introduction-first-signed-commit
                                 intro))
                              (signer
                               ,(openpgp-format-fingerprint
                                 (channel-introduction-first-commit-signer
                                  intro))))))
                          '()))))))))

  (mlet* %store-monad ((derivations (channel-instance-derivations instances))
                       (entries ->  (map instance->entry instances derivations)))
    (return (manifest entries))))

(define (package-cache-file manifest)
  "Build a package cache file for the instance in MANIFEST.  This is meant to
be used as a profile hook."
  (let ((profile (profile (content manifest) (hooks '()))))
    (define build
      #~(begin
          (use-modules (gnu packages))

          (if (defined? 'generate-package-cache)
              (begin
                ;; Delegate package cache generation to the inferior.
                (format (current-error-port)
                        "Generating package cache for '~a'...~%"
                        #$profile)
                (generate-package-cache #$output))
              (mkdir #$output))))

    (gexp->derivation-in-inferior "guix-package-cache" build
                                  profile

                                  ;; If the Guix in PROFILE is too old and
                                  ;; lacks 'guix repl', don't build the cache
                                  ;; instead of failing.
                                  #:silent-failure? #t

                                  #:properties '((type . profile-hook)
                                                 (hook . package-cache))
                                  #:local-build? #t)))

(define %channel-profile-hooks
  ;; The default channel profile hooks.
  (cons package-cache-file %default-profile-hooks))

(define (channel-instances->derivation instances)
  "Return the derivation of the profile containing INSTANCES, a list of
channel instances."
  (mlet %store-monad ((manifest (channel-instances->manifest instances)))
    (profile-derivation manifest
                        #:hooks %channel-profile-hooks)))

(define latest-channel-instances*
  (store-lift latest-channel-instances))

(define* (latest-channel-derivation #:optional (channels %default-channels)
                                    #:key
                                    (current-channels '())
                                    (validate-pull
                                     ensure-forward-channel-update))
  "Return as a monadic value the derivation that builds the profile for the
latest instances of CHANNELS.  CURRENT-CHANNELS and VALIDATE-PULL are passed
to 'latest-channel-instances'."
  (mlet %store-monad ((instances
                       (latest-channel-instances* channels
                                                  #:current-channels
                                                  current-channels
                                                  #:validate-pull
                                                  validate-pull)))
    (channel-instances->derivation instances)))

(define (profile-channels profile)
  "Return the list of channels corresponding to entries in PROFILE.  If
PROFILE is not a profile created by 'guix pull', return the empty list."
  (filter-map (lambda (entry)
                (match (assq 'source (manifest-entry-properties entry))
                  (('source ('repository ('version 0)
                                         ('url url)
                                         ('branch branch)
                                         ('commit commit)
                                         rest ...))
                   (channel (name (string->symbol
                                   (manifest-entry-name entry)))
                            (url url)
                            (commit commit)
                            (introduction
                             (match (assq 'introduction rest)
                               (#f #f)
                               (('introduction intro)
                                (sexp->channel-introduction intro))))))

                  ;; No channel information for this manifest entry.
                  ;; XXX: Pre-0.15.0 Guix did not provide that information,
                  ;; but there's not much we can do in that case.
                  (_ #f)))

              ;; Show most recently installed packages last.
              (reverse
               (manifest-entries (profile-manifest profile)))))

\f
;;;
;;; News.
;;;

;; Channel news.
(define-record-type <channel-news>
  (channel-news entries)
  channel-news?
  (entries channel-news-entries))                 ;list of <channel-news-entry>

;; News entry, associated with a specific commit of the channel.
(define-record-type <channel-news-entry>
  (channel-news-entry commit tag title body)
  channel-news-entry?
  (commit  channel-news-entry-commit)             ;hex string | #f
  (tag     channel-news-entry-tag)                ;#f | string
  (title   channel-news-entry-title)              ;list of language tag/string pairs
  (body    channel-news-entry-body))              ;list of language tag/string pairs

(define (sexp->channel-news-entry entry)
  "Return the <channel-news-entry> record corresponding to ENTRY, an sexp."
  (define (pair language message)
    (cons (symbol->string language) message))

  (match entry
    (('entry ((and (or 'commit 'tag) type) commit-or-tag)
             ('title ((? symbol? title-tags) (? string? titles)) ...)
             ('body ((? symbol? body-tags) (? string? bodies)) ...)
             _ ...)
     (channel-news-entry (and (eq? type 'commit) commit-or-tag)
                         (and (eq? type 'tag) commit-or-tag)
                         (map pair title-tags titles)
                         (map pair body-tags bodies)))
    (_
     (raise (condition
             (&message (message "invalid channel news entry"))
             (&error-location
              (location (source-properties->location
                         (source-properties entry)))))))))

(define (read-channel-news port)
  "Read a channel news feed from PORT and return it as a <channel-news>
record."
  (match (false-if-exception (read port))
    (('channel-news ('version 0) entries ...)
     (channel-news (map sexp->channel-news-entry entries)))
    (('channel-news ('version version) _ ...)
     ;; This is an unsupported version from the future.  There's nothing wrong
     ;; with that (the user may simply need to upgrade the 'guix' channel to
     ;; be able to read it), so silently ignore it.
     (channel-news '()))
    (#f
     (raise (condition
             (&message (message "syntactically invalid channel news file")))))
    (sexp
     (raise (condition
             (&message (message "invalid channel news file"))
             (&error-location
              (location (source-properties->location
                         (source-properties sexp)))))))))

(define (resolve-channel-news-entry-tag repository entry)
  "If ENTRY has its 'commit' field set, return ENTRY.  Otherwise, lookup
ENTRY's 'tag' in REPOSITORY and return ENTRY with its 'commit' field set to
the field its 'tag' refers to.  A 'git-error' exception is raised if the tag
cannot be found."
  (if (channel-news-entry-commit entry)
      entry
      (let* ((tag       (channel-news-entry-tag entry))
             (reference (string-append "refs/tags/" tag))
             (oid       (reference-name->oid repository reference)))
        (channel-news-entry (oid->string oid) tag
                            (channel-news-entry-title entry)
                            (channel-news-entry-body entry)))))

(define* (channel-news-for-commit channel new #:optional old)
  "Return a list of <channel-news-entry> for CHANNEL between commits OLD and
NEW.  When OLD is omitted or is #f, return all the news entries of CHANNEL."
  (catch 'git-error
    (lambda ()
      (let* ((checkout  (update-cached-checkout (channel-url channel)
                                                #:ref `(commit . ,new)))
             (metadata  (read-channel-metadata-from-source checkout))
             (news-file (channel-metadata-news-file metadata))
             (news-file (and news-file
                             (string-append checkout "/" news-file))))
        (if (and news-file (file-exists? news-file))
            (with-repository checkout repository
              (let* ((news    (call-with-input-file news-file
                                read-channel-news))
                     (entries (map (lambda (entry)
                                     (resolve-channel-news-entry-tag repository
                                                                     entry))
                                   (channel-news-entries news))))
                (if old
                    (let* ((new     (commit-lookup repository (string->oid new)))
                           (old     (commit-lookup repository (string->oid old)))
                           (commits (list->set
                                     (map (compose oid->string commit-id)
                                          (commit-difference new old)))))
                      (filter (lambda (entry)
                                (set-contains? commits
                                               (channel-news-entry-commit entry)))
                              entries))
                    entries)))
            '())))
    (lambda (key error . rest)
      ;; If commit NEW or commit OLD cannot be found, then something must be
      ;; wrong (for example, the history of CHANNEL was rewritten and these
      ;; commits no longer exist upstream), so quietly return the empty list.
      (if (= GIT_ENOTFOUND (git-error-code error))
          '()
          (apply throw key error rest)))))

;;; Local Variables:
;;; eval: (put 'with-guile 'scheme-indent-function 1)
;;; End:

debug log:

solving ad2442f50e ...
found ad2442f50e in https://git.savannah.gnu.org/cgit/guix.git

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/guix.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).