contrib / mw-to-git / git-remote-mediawiki.perlon commit Merge branch 'maint' (4d1c565)
   1#! /usr/bin/perl
   2
   3# Copyright (C) 2011
   4#     Jérémie Nikaes <jeremie.nikaes@ensimag.imag.fr>
   5#     Arnaud Lacurie <arnaud.lacurie@ensimag.imag.fr>
   6#     Claire Fousse <claire.fousse@ensimag.imag.fr>
   7#     David Amouyal <david.amouyal@ensimag.imag.fr>
   8#     Matthieu Moy <matthieu.moy@grenoble-inp.fr>
   9# License: GPL v2 or later
  10
  11# Gateway between Git and MediaWiki.
  12# Documentation & bugtracker: https://github.com/moy/Git-Mediawiki/
  13
  14use strict;
  15use MediaWiki::API;
  16use DateTime::Format::ISO8601;
  17
  18# By default, use UTF-8 to communicate with Git and the user
  19binmode STDERR, ":utf8";
  20binmode STDOUT, ":utf8";
  21
  22use URI::Escape;
  23use IPC::Open2;
  24
  25use warnings;
  26
  27# Mediawiki filenames can contain forward slashes. This variable decides by which pattern they should be replaced
  28use constant SLASH_REPLACEMENT => "%2F";
  29
  30# It's not always possible to delete pages (may require some
  31# privileges). Deleted pages are replaced with this content.
  32use constant DELETED_CONTENT => "[[Category:Deleted]]\n";
  33
  34# It's not possible to create empty pages. New empty files in Git are
  35# sent with this content instead.
  36use constant EMPTY_CONTENT => "<!-- empty page -->\n";
  37
  38# used to reflect file creation or deletion in diff.
  39use constant NULL_SHA1 => "0000000000000000000000000000000000000000";
  40
  41# Used on Git's side to reflect empty edit messages on the wiki
  42use constant EMPTY_MESSAGE => '*Empty MediaWiki Message*';
  43
  44my $remotename = $ARGV[0];
  45my $url = $ARGV[1];
  46
  47# Accept both space-separated and multiple keys in config file.
  48# Spaces should be written as _ anyway because we'll use chomp.
  49my @tracked_pages = split(/[ \n]/, run_git("config --get-all remote.". $remotename .".pages"));
  50chomp(@tracked_pages);
  51
  52# Just like @tracked_pages, but for MediaWiki categories.
  53my @tracked_categories = split(/[ \n]/, run_git("config --get-all remote.". $remotename .".categories"));
  54chomp(@tracked_categories);
  55
  56# Import media files on pull
  57my $import_media = run_git("config --get --bool remote.". $remotename .".mediaimport");
  58chomp($import_media);
  59$import_media = ($import_media eq "true");
  60
  61# Export media files on push
  62my $export_media = run_git("config --get --bool remote.". $remotename .".mediaexport");
  63chomp($export_media);
  64$export_media = !($export_media eq "false");
  65
  66my $wiki_login = run_git("config --get remote.". $remotename .".mwLogin");
  67# Note: mwPassword is discourraged. Use the credential system instead.
  68my $wiki_passwd = run_git("config --get remote.". $remotename .".mwPassword");
  69my $wiki_domain = run_git("config --get remote.". $remotename .".mwDomain");
  70chomp($wiki_login);
  71chomp($wiki_passwd);
  72chomp($wiki_domain);
  73
  74# Import only last revisions (both for clone and fetch)
  75my $shallow_import = run_git("config --get --bool remote.". $remotename .".shallow");
  76chomp($shallow_import);
  77$shallow_import = ($shallow_import eq "true");
  78
  79# Fetch (clone and pull) by revisions instead of by pages. This behavior
  80# is more efficient when we have a wiki with lots of pages and we fetch
  81# the revisions quite often so that they concern only few pages.
  82# Possible values:
  83# - by_rev: perform one query per new revision on the remote wiki
  84# - by_page: query each tracked page for new revision
  85my $fetch_strategy = run_git("config --get remote.$remotename.fetchStrategy");
  86unless ($fetch_strategy) {
  87        $fetch_strategy = run_git("config --get mediawiki.fetchStrategy");
  88}
  89chomp($fetch_strategy);
  90unless ($fetch_strategy) {
  91        $fetch_strategy = "by_page";
  92}
  93
  94# Dumb push: don't update notes and mediawiki ref to reflect the last push.
  95#
  96# Configurable with mediawiki.dumbPush, or per-remote with
  97# remote.<remotename>.dumbPush.
  98#
  99# This means the user will have to re-import the just-pushed
 100# revisions. On the other hand, this means that the Git revisions
 101# corresponding to MediaWiki revisions are all imported from the wiki,
 102# regardless of whether they were initially created in Git or from the
 103# web interface, hence all users will get the same history (i.e. if
 104# the push from Git to MediaWiki loses some information, everybody
 105# will get the history with information lost). If the import is
 106# deterministic, this means everybody gets the same sha1 for each
 107# MediaWiki revision.
 108my $dumb_push = run_git("config --get --bool remote.$remotename.dumbPush");
 109unless ($dumb_push) {
 110        $dumb_push = run_git("config --get --bool mediawiki.dumbPush");
 111}
 112chomp($dumb_push);
 113$dumb_push = ($dumb_push eq "true");
 114
 115my $wiki_name = $url;
 116$wiki_name =~ s/[^\/]*:\/\///;
 117# If URL is like http://user:password@example.com/, we clearly don't
 118# want the password in $wiki_name. While we're there, also remove user
 119# and '@' sign, to avoid author like MWUser@HTTPUser@host.com
 120$wiki_name =~ s/^.*@//;
 121
 122# Commands parser
 123my $entry;
 124my @cmd;
 125while (<STDIN>) {
 126        chomp;
 127        @cmd = split(/ /);
 128        if (defined($cmd[0])) {
 129                # Line not blank
 130                if ($cmd[0] eq "capabilities") {
 131                        die("Too many arguments for capabilities") unless (!defined($cmd[1]));
 132                        mw_capabilities();
 133                } elsif ($cmd[0] eq "list") {
 134                        die("Too many arguments for list") unless (!defined($cmd[2]));
 135                        mw_list($cmd[1]);
 136                } elsif ($cmd[0] eq "import") {
 137                        die("Invalid arguments for import") unless ($cmd[1] ne "" && !defined($cmd[2]));
 138                        mw_import($cmd[1]);
 139                } elsif ($cmd[0] eq "option") {
 140                        die("Too many arguments for option") unless ($cmd[1] ne "" && $cmd[2] ne "" && !defined($cmd[3]));
 141                        mw_option($cmd[1],$cmd[2]);
 142                } elsif ($cmd[0] eq "push") {
 143                        mw_push($cmd[1]);
 144                } else {
 145                        print STDERR "Unknown command. Aborting...\n";
 146                        last;
 147                }
 148        } else {
 149                # blank line: we should terminate
 150                last;
 151        }
 152
 153        BEGIN { $| = 1 } # flush STDOUT, to make sure the previous
 154                         # command is fully processed.
 155}
 156
 157########################## Functions ##############################
 158
 159## credential API management (generic functions)
 160
 161sub credential_read {
 162        my %credential;
 163        my $reader = shift;
 164        my $op = shift;
 165        while (<$reader>) {
 166                my ($key, $value) = /([^=]*)=(.*)/;
 167                if (not defined $key) {
 168                        die "ERROR receiving response from git credential $op:\n$_\n";
 169                }
 170                $credential{$key} = $value;
 171        }
 172        return %credential;
 173}
 174
 175sub credential_write {
 176        my $credential = shift;
 177        my $writer = shift;
 178        # url overwrites other fields, so it must come first
 179        print $writer "url=$credential->{url}\n" if exists $credential->{url};
 180        while (my ($key, $value) = each(%$credential) ) {
 181                if (length $value && $key ne 'url') {
 182                        print $writer "$key=$value\n";
 183                }
 184        }
 185}
 186
 187sub credential_run {
 188        my $op = shift;
 189        my $credential = shift;
 190        my $pid = open2(my $reader, my $writer, "git credential $op");
 191        credential_write($credential, $writer);
 192        print $writer "\n";
 193        close($writer);
 194
 195        if ($op eq "fill") {
 196                %$credential = credential_read($reader, $op);
 197        } else {
 198                if (<$reader>) {
 199                        die "ERROR while running git credential $op:\n$_";
 200                }
 201        }
 202        close($reader);
 203        waitpid($pid, 0);
 204        my $child_exit_status = $? >> 8;
 205        if ($child_exit_status != 0) {
 206                die "'git credential $op' failed with code $child_exit_status.";
 207        }
 208}
 209
 210# MediaWiki API instance, created lazily.
 211my $mediawiki;
 212
 213sub mw_connect_maybe {
 214        if ($mediawiki) {
 215                return;
 216        }
 217        $mediawiki = MediaWiki::API->new;
 218        $mediawiki->{config}->{api_url} = "$url/api.php";
 219        if ($wiki_login) {
 220                my %credential = (url => $url);
 221                $credential{username} = $wiki_login;
 222                $credential{password} = $wiki_passwd;
 223                credential_run("fill", \%credential);
 224                my $request = {lgname => $credential{username},
 225                               lgpassword => $credential{password},
 226                               lgdomain => $wiki_domain};
 227                if ($mediawiki->login($request)) {
 228                        credential_run("approve", \%credential);
 229                        print STDERR "Logged in mediawiki user \"$credential{username}\".\n";
 230                } else {
 231                        print STDERR "Failed to log in mediawiki user \"$credential{username}\" on $url\n";
 232                        print STDERR "  (error " .
 233                                $mediawiki->{error}->{code} . ': ' .
 234                                $mediawiki->{error}->{details} . ")\n";
 235                        credential_run("reject", \%credential);
 236                        exit 1;
 237                }
 238        }
 239}
 240
 241sub fatal_mw_error {
 242        my $action = shift;
 243        print STDERR "fatal: could not $action.\n";
 244        print STDERR "fatal: '$url' does not appear to be a mediawiki\n";
 245        if ($url =~ /^https/) {
 246                print STDERR "fatal: make sure '$url/api.php' is a valid page\n";
 247                print STDERR "fatal: and the SSL certificate is correct.\n";
 248        } else {
 249                print STDERR "fatal: make sure '$url/api.php' is a valid page.\n";
 250        }
 251        print STDERR "fatal: (error " .
 252            $mediawiki->{error}->{code} . ': ' .
 253            $mediawiki->{error}->{details} . ")\n";
 254        exit 1;
 255}
 256
 257## Functions for listing pages on the remote wiki
 258sub get_mw_tracked_pages {
 259        my $pages = shift;
 260        get_mw_page_list(\@tracked_pages, $pages);
 261}
 262
 263sub get_mw_page_list {
 264        my $page_list = shift;
 265        my $pages = shift;
 266        my @some_pages = @$page_list;
 267        while (@some_pages) {
 268                my $last = 50;
 269                if ($#some_pages < $last) {
 270                        $last = $#some_pages;
 271                }
 272                my @slice = @some_pages[0..$last];
 273                get_mw_first_pages(\@slice, $pages);
 274                @some_pages = @some_pages[51..$#some_pages];
 275        }
 276}
 277
 278sub get_mw_tracked_categories {
 279        my $pages = shift;
 280        foreach my $category (@tracked_categories) {
 281                if (index($category, ':') < 0) {
 282                        # Mediawiki requires the Category
 283                        # prefix, but let's not force the user
 284                        # to specify it.
 285                        $category = "Category:" . $category;
 286                }
 287                my $mw_pages = $mediawiki->list( {
 288                        action => 'query',
 289                        list => 'categorymembers',
 290                        cmtitle => $category,
 291                        cmlimit => 'max' } )
 292                        || die $mediawiki->{error}->{code} . ': '
 293                                . $mediawiki->{error}->{details};
 294                foreach my $page (@{$mw_pages}) {
 295                        $pages->{$page->{title}} = $page;
 296                }
 297        }
 298}
 299
 300sub get_mw_all_pages {
 301        my $pages = shift;
 302        # No user-provided list, get the list of pages from the API.
 303        my $mw_pages = $mediawiki->list({
 304                action => 'query',
 305                list => 'allpages',
 306                aplimit => 'max'
 307        });
 308        if (!defined($mw_pages)) {
 309                fatal_mw_error("get the list of wiki pages");
 310        }
 311        foreach my $page (@{$mw_pages}) {
 312                $pages->{$page->{title}} = $page;
 313        }
 314}
 315
 316# queries the wiki for a set of pages. Meant to be used within a loop
 317# querying the wiki for slices of page list.
 318sub get_mw_first_pages {
 319        my $some_pages = shift;
 320        my @some_pages = @{$some_pages};
 321
 322        my $pages = shift;
 323
 324        # pattern 'page1|page2|...' required by the API
 325        my $titles = join('|', @some_pages);
 326
 327        my $mw_pages = $mediawiki->api({
 328                action => 'query',
 329                titles => $titles,
 330        });
 331        if (!defined($mw_pages)) {
 332                fatal_mw_error("query the list of wiki pages");
 333        }
 334        while (my ($id, $page) = each(%{$mw_pages->{query}->{pages}})) {
 335                if ($id < 0) {
 336                        print STDERR "Warning: page $page->{title} not found on wiki\n";
 337                } else {
 338                        $pages->{$page->{title}} = $page;
 339                }
 340        }
 341}
 342
 343# Get the list of pages to be fetched according to configuration.
 344sub get_mw_pages {
 345        mw_connect_maybe();
 346
 347        print STDERR "Listing pages on remote wiki...\n";
 348
 349        my %pages; # hash on page titles to avoid duplicates
 350        my $user_defined;
 351        if (@tracked_pages) {
 352                $user_defined = 1;
 353                # The user provided a list of pages titles, but we
 354                # still need to query the API to get the page IDs.
 355                get_mw_tracked_pages(\%pages);
 356        }
 357        if (@tracked_categories) {
 358                $user_defined = 1;
 359                get_mw_tracked_categories(\%pages);
 360        }
 361        if (!$user_defined) {
 362                get_mw_all_pages(\%pages);
 363        }
 364        if ($import_media) {
 365                print STDERR "Getting media files for selected pages...\n";
 366                if ($user_defined) {
 367                        get_linked_mediafiles(\%pages);
 368                } else {
 369                        get_all_mediafiles(\%pages);
 370                }
 371        }
 372        print STDERR (scalar keys %pages) . " pages found.\n";
 373        return %pages;
 374}
 375
 376# usage: $out = run_git("command args");
 377#        $out = run_git("command args", "raw"); # don't interpret output as UTF-8.
 378sub run_git {
 379        my $args = shift;
 380        my $encoding = (shift || "encoding(UTF-8)");
 381        open(my $git, "-|:$encoding", "git " . $args);
 382        my $res = do { local $/; <$git> };
 383        close($git);
 384
 385        return $res;
 386}
 387
 388
 389sub get_all_mediafiles {
 390        my $pages = shift;
 391        # Attach list of all pages for media files from the API,
 392        # they are in a different namespace, only one namespace
 393        # can be queried at the same moment
 394        my $mw_pages = $mediawiki->list({
 395                action => 'query',
 396                list => 'allpages',
 397                apnamespace => get_mw_namespace_id("File"),
 398                aplimit => 'max'
 399        });
 400        if (!defined($mw_pages)) {
 401                print STDERR "fatal: could not get the list of pages for media files.\n";
 402                print STDERR "fatal: '$url' does not appear to be a mediawiki\n";
 403                print STDERR "fatal: make sure '$url/api.php' is a valid page.\n";
 404                exit 1;
 405        }
 406        foreach my $page (@{$mw_pages}) {
 407                $pages->{$page->{title}} = $page;
 408        }
 409}
 410
 411sub get_linked_mediafiles {
 412        my $pages = shift;
 413        my @titles = map $_->{title}, values(%{$pages});
 414
 415        # The query is split in small batches because of the MW API limit of
 416        # the number of links to be returned (500 links max).
 417        my $batch = 10;
 418        while (@titles) {
 419                if ($#titles < $batch) {
 420                        $batch = $#titles;
 421                }
 422                my @slice = @titles[0..$batch];
 423
 424                # pattern 'page1|page2|...' required by the API
 425                my $mw_titles = join('|', @slice);
 426
 427                # Media files could be included or linked from
 428                # a page, get all related
 429                my $query = {
 430                        action => 'query',
 431                        prop => 'links|images',
 432                        titles => $mw_titles,
 433                        plnamespace => get_mw_namespace_id("File"),
 434                        pllimit => 'max'
 435                };
 436                my $result = $mediawiki->api($query);
 437
 438                while (my ($id, $page) = each(%{$result->{query}->{pages}})) {
 439                        my @media_titles;
 440                        if (defined($page->{links})) {
 441                                my @link_titles = map $_->{title}, @{$page->{links}};
 442                                push(@media_titles, @link_titles);
 443                        }
 444                        if (defined($page->{images})) {
 445                                my @image_titles = map $_->{title}, @{$page->{images}};
 446                                push(@media_titles, @image_titles);
 447                        }
 448                        if (@media_titles) {
 449                                get_mw_page_list(\@media_titles, $pages);
 450                        }
 451                }
 452
 453                @titles = @titles[($batch+1)..$#titles];
 454        }
 455}
 456
 457sub get_mw_mediafile_for_page_revision {
 458        # Name of the file on Wiki, with the prefix.
 459        my $filename = shift;
 460        my $timestamp = shift;
 461        my %mediafile;
 462
 463        # Search if on a media file with given timestamp exists on
 464        # MediaWiki. In that case download the file.
 465        my $query = {
 466                action => 'query',
 467                prop => 'imageinfo',
 468                titles => "File:" . $filename,
 469                iistart => $timestamp,
 470                iiend => $timestamp,
 471                iiprop => 'timestamp|archivename|url',
 472                iilimit => 1
 473        };
 474        my $result = $mediawiki->api($query);
 475
 476        my ($fileid, $file) = each( %{$result->{query}->{pages}} );
 477        # If not defined it means there is no revision of the file for
 478        # given timestamp.
 479        if (defined($file->{imageinfo})) {
 480                $mediafile{title} = $filename;
 481
 482                my $fileinfo = pop(@{$file->{imageinfo}});
 483                $mediafile{timestamp} = $fileinfo->{timestamp};
 484                # Mediawiki::API's download function doesn't support https URLs
 485                # and can't download old versions of files.
 486                print STDERR "\tDownloading file $mediafile{title}, version $mediafile{timestamp}\n";
 487                $mediafile{content} = download_mw_mediafile($fileinfo->{url});
 488        }
 489        return %mediafile;
 490}
 491
 492sub download_mw_mediafile {
 493        my $url = shift;
 494
 495        my $response = $mediawiki->{ua}->get($url);
 496        if ($response->code == 200) {
 497                return $response->decoded_content;
 498        } else {
 499                print STDERR "Error downloading mediafile from :\n";
 500                print STDERR "URL: $url\n";
 501                print STDERR "Server response: " . $response->code . " " . $response->message . "\n";
 502                exit 1;
 503        }
 504}
 505
 506sub get_last_local_revision {
 507        # Get note regarding last mediawiki revision
 508        my $note = run_git("notes --ref=$remotename/mediawiki show refs/mediawiki/$remotename/master 2>/dev/null");
 509        my @note_info = split(/ /, $note);
 510
 511        my $lastrevision_number;
 512        if (!(defined($note_info[0]) && $note_info[0] eq "mediawiki_revision:")) {
 513                print STDERR "No previous mediawiki revision found";
 514                $lastrevision_number = 0;
 515        } else {
 516                # Notes are formatted : mediawiki_revision: #number
 517                $lastrevision_number = $note_info[1];
 518                chomp($lastrevision_number);
 519                print STDERR "Last local mediawiki revision found is $lastrevision_number";
 520        }
 521        return $lastrevision_number;
 522}
 523
 524# Remember the timestamp corresponding to a revision id.
 525my %basetimestamps;
 526
 527# Get the last remote revision without taking in account which pages are
 528# tracked or not. This function makes a single request to the wiki thus
 529# avoid a loop onto all tracked pages. This is useful for the fetch-by-rev
 530# option.
 531sub get_last_global_remote_rev {
 532        mw_connect_maybe();
 533
 534        my $query = {
 535                action => 'query',
 536                list => 'recentchanges',
 537                prop => 'revisions',
 538                rclimit => '1',
 539                rcdir => 'older',
 540        };
 541        my $result = $mediawiki->api($query);
 542        return $result->{query}->{recentchanges}[0]->{revid};
 543}
 544
 545# Get the last remote revision concerning the tracked pages and the tracked
 546# categories.
 547sub get_last_remote_revision {
 548        mw_connect_maybe();
 549
 550        my %pages_hash = get_mw_pages();
 551        my @pages = values(%pages_hash);
 552
 553        my $max_rev_num = 0;
 554
 555        print STDERR "Getting last revision id on tracked pages...\n";
 556
 557        foreach my $page (@pages) {
 558                my $id = $page->{pageid};
 559
 560                my $query = {
 561                        action => 'query',
 562                        prop => 'revisions',
 563                        rvprop => 'ids|timestamp',
 564                        pageids => $id,
 565                };
 566
 567                my $result = $mediawiki->api($query);
 568
 569                my $lastrev = pop(@{$result->{query}->{pages}->{$id}->{revisions}});
 570
 571                $basetimestamps{$lastrev->{revid}} = $lastrev->{timestamp};
 572
 573                $max_rev_num = ($lastrev->{revid} > $max_rev_num ? $lastrev->{revid} : $max_rev_num);
 574        }
 575
 576        print STDERR "Last remote revision found is $max_rev_num.\n";
 577        return $max_rev_num;
 578}
 579
 580# Clean content before sending it to MediaWiki
 581sub mediawiki_clean {
 582        my $string = shift;
 583        my $page_created = shift;
 584        # Mediawiki does not allow blank space at the end of a page and ends with a single \n.
 585        # This function right trims a string and adds a \n at the end to follow this rule
 586        $string =~ s/\s+$//;
 587        if ($string eq "" && $page_created) {
 588                # Creating empty pages is forbidden.
 589                $string = EMPTY_CONTENT;
 590        }
 591        return $string."\n";
 592}
 593
 594# Filter applied on MediaWiki data before adding them to Git
 595sub mediawiki_smudge {
 596        my $string = shift;
 597        if ($string eq EMPTY_CONTENT) {
 598                $string = "";
 599        }
 600        # This \n is important. This is due to mediawiki's way to handle end of files.
 601        return $string."\n";
 602}
 603
 604sub mediawiki_clean_filename {
 605        my $filename = shift;
 606        $filename =~ s/@{[SLASH_REPLACEMENT]}/\//g;
 607        # [, ], |, {, and } are forbidden by MediaWiki, even URL-encoded.
 608        # Do a variant of URL-encoding, i.e. looks like URL-encoding,
 609        # but with _ added to prevent MediaWiki from thinking this is
 610        # an actual special character.
 611        $filename =~ s/[\[\]\{\}\|]/sprintf("_%%_%x", ord($&))/ge;
 612        # If we use the uri escape before
 613        # we should unescape here, before anything
 614
 615        return $filename;
 616}
 617
 618sub mediawiki_smudge_filename {
 619        my $filename = shift;
 620        $filename =~ s/\//@{[SLASH_REPLACEMENT]}/g;
 621        $filename =~ s/ /_/g;
 622        # Decode forbidden characters encoded in mediawiki_clean_filename
 623        $filename =~ s/_%_([0-9a-fA-F][0-9a-fA-F])/sprintf("%c", hex($1))/ge;
 624        return $filename;
 625}
 626
 627sub literal_data {
 628        my ($content) = @_;
 629        print STDOUT "data ", bytes::length($content), "\n", $content;
 630}
 631
 632sub literal_data_raw {
 633        # Output possibly binary content.
 634        my ($content) = @_;
 635        # Avoid confusion between size in bytes and in characters
 636        utf8::downgrade($content);
 637        binmode STDOUT, ":raw";
 638        print STDOUT "data ", bytes::length($content), "\n", $content;
 639        binmode STDOUT, ":utf8";
 640}
 641
 642sub mw_capabilities {
 643        # Revisions are imported to the private namespace
 644        # refs/mediawiki/$remotename/ by the helper and fetched into
 645        # refs/remotes/$remotename later by fetch.
 646        print STDOUT "refspec refs/heads/*:refs/mediawiki/$remotename/*\n";
 647        print STDOUT "import\n";
 648        print STDOUT "list\n";
 649        print STDOUT "push\n";
 650        print STDOUT "\n";
 651}
 652
 653sub mw_list {
 654        # MediaWiki do not have branches, we consider one branch arbitrarily
 655        # called master, and HEAD pointing to it.
 656        print STDOUT "? refs/heads/master\n";
 657        print STDOUT "\@refs/heads/master HEAD\n";
 658        print STDOUT "\n";
 659}
 660
 661sub mw_option {
 662        print STDERR "remote-helper command 'option $_[0]' not yet implemented\n";
 663        print STDOUT "unsupported\n";
 664}
 665
 666sub fetch_mw_revisions_for_page {
 667        my $page = shift;
 668        my $id = shift;
 669        my $fetch_from = shift;
 670        my @page_revs = ();
 671        my $query = {
 672                action => 'query',
 673                prop => 'revisions',
 674                rvprop => 'ids',
 675                rvdir => 'newer',
 676                rvstartid => $fetch_from,
 677                rvlimit => 500,
 678                pageids => $id,
 679        };
 680
 681        my $revnum = 0;
 682        # Get 500 revisions at a time due to the mediawiki api limit
 683        while (1) {
 684                my $result = $mediawiki->api($query);
 685
 686                # Parse each of those 500 revisions
 687                foreach my $revision (@{$result->{query}->{pages}->{$id}->{revisions}}) {
 688                        my $page_rev_ids;
 689                        $page_rev_ids->{pageid} = $page->{pageid};
 690                        $page_rev_ids->{revid} = $revision->{revid};
 691                        push(@page_revs, $page_rev_ids);
 692                        $revnum++;
 693                }
 694                last unless $result->{'query-continue'};
 695                $query->{rvstartid} = $result->{'query-continue'}->{revisions}->{rvstartid};
 696        }
 697        if ($shallow_import && @page_revs) {
 698                print STDERR "  Found 1 revision (shallow import).\n";
 699                @page_revs = sort {$b->{revid} <=> $a->{revid}} (@page_revs);
 700                return $page_revs[0];
 701        }
 702        print STDERR "  Found ", $revnum, " revision(s).\n";
 703        return @page_revs;
 704}
 705
 706sub fetch_mw_revisions {
 707        my $pages = shift; my @pages = @{$pages};
 708        my $fetch_from = shift;
 709
 710        my @revisions = ();
 711        my $n = 1;
 712        foreach my $page (@pages) {
 713                my $id = $page->{pageid};
 714
 715                print STDERR "page $n/", scalar(@pages), ": ". $page->{title} ."\n";
 716                $n++;
 717                my @page_revs = fetch_mw_revisions_for_page($page, $id, $fetch_from);
 718                @revisions = (@page_revs, @revisions);
 719        }
 720
 721        return ($n, @revisions);
 722}
 723
 724sub fe_escape_path {
 725    my $path = shift;
 726    $path =~ s/\\/\\\\/g;
 727    $path =~ s/"/\\"/g;
 728    $path =~ s/\n/\\n/g;
 729    return '"' . $path . '"';
 730}
 731
 732sub import_file_revision {
 733        my $commit = shift;
 734        my %commit = %{$commit};
 735        my $full_import = shift;
 736        my $n = shift;
 737        my $mediafile = shift;
 738        my %mediafile;
 739        if ($mediafile) {
 740                %mediafile = %{$mediafile};
 741        }
 742
 743        my $title = $commit{title};
 744        my $comment = $commit{comment};
 745        my $content = $commit{content};
 746        my $author = $commit{author};
 747        my $date = $commit{date};
 748
 749        print STDOUT "commit refs/mediawiki/$remotename/master\n";
 750        print STDOUT "mark :$n\n";
 751        print STDOUT "committer $author <$author\@$wiki_name> ", $date->epoch, " +0000\n";
 752        literal_data($comment);
 753
 754        # If it's not a clone, we need to know where to start from
 755        if (!$full_import && $n == 1) {
 756                print STDOUT "from refs/mediawiki/$remotename/master^0\n";
 757        }
 758        if ($content ne DELETED_CONTENT) {
 759                print STDOUT "M 644 inline " .
 760                    fe_escape_path($title . ".mw") . "\n";
 761                literal_data($content);
 762                if (%mediafile) {
 763                        print STDOUT "M 644 inline "
 764                            . fe_escape_path($mediafile{title}) . "\n";
 765                        literal_data_raw($mediafile{content});
 766                }
 767                print STDOUT "\n\n";
 768        } else {
 769                print STDOUT "D " . fe_escape_path($title . ".mw") . "\n";
 770        }
 771
 772        # mediawiki revision number in the git note
 773        if ($full_import && $n == 1) {
 774                print STDOUT "reset refs/notes/$remotename/mediawiki\n";
 775        }
 776        print STDOUT "commit refs/notes/$remotename/mediawiki\n";
 777        print STDOUT "committer $author <$author\@$wiki_name> ", $date->epoch, " +0000\n";
 778        literal_data("Note added by git-mediawiki during import");
 779        if (!$full_import && $n == 1) {
 780                print STDOUT "from refs/notes/$remotename/mediawiki^0\n";
 781        }
 782        print STDOUT "N inline :$n\n";
 783        literal_data("mediawiki_revision: " . $commit{mw_revision});
 784        print STDOUT "\n\n";
 785}
 786
 787# parse a sequence of
 788# <cmd> <arg1>
 789# <cmd> <arg2>
 790# \n
 791# (like batch sequence of import and sequence of push statements)
 792sub get_more_refs {
 793        my $cmd = shift;
 794        my @refs;
 795        while (1) {
 796                my $line = <STDIN>;
 797                if ($line =~ m/^$cmd (.*)$/) {
 798                        push(@refs, $1);
 799                } elsif ($line eq "\n") {
 800                        return @refs;
 801                } else {
 802                        die("Invalid command in a '$cmd' batch: ". $_);
 803                }
 804        }
 805}
 806
 807sub mw_import {
 808        # multiple import commands can follow each other.
 809        my @refs = (shift, get_more_refs("import"));
 810        foreach my $ref (@refs) {
 811                mw_import_ref($ref);
 812        }
 813        print STDOUT "done\n";
 814}
 815
 816sub mw_import_ref {
 817        my $ref = shift;
 818        # The remote helper will call "import HEAD" and
 819        # "import refs/heads/master".
 820        # Since HEAD is a symbolic ref to master (by convention,
 821        # followed by the output of the command "list" that we gave),
 822        # we don't need to do anything in this case.
 823        if ($ref eq "HEAD") {
 824                return;
 825        }
 826
 827        mw_connect_maybe();
 828
 829        print STDERR "Searching revisions...\n";
 830        my $last_local = get_last_local_revision();
 831        my $fetch_from = $last_local + 1;
 832        if ($fetch_from == 1) {
 833                print STDERR ", fetching from beginning.\n";
 834        } else {
 835                print STDERR ", fetching from here.\n";
 836        }
 837
 838        my $n = 0;
 839        if ($fetch_strategy eq "by_rev") {
 840                print STDERR "Fetching & writing export data by revs...\n";
 841                $n = mw_import_ref_by_revs($fetch_from);
 842        } elsif ($fetch_strategy eq "by_page") {
 843                print STDERR "Fetching & writing export data by pages...\n";
 844                $n = mw_import_ref_by_pages($fetch_from);
 845        } else {
 846                print STDERR "fatal: invalid fetch strategy \"$fetch_strategy\".\n";
 847                print STDERR "Check your configuration variables remote.$remotename.fetchStrategy and mediawiki.fetchStrategy\n";
 848                exit 1;
 849        }
 850
 851        if ($fetch_from == 1 && $n == 0) {
 852                print STDERR "You appear to have cloned an empty MediaWiki.\n";
 853                # Something has to be done remote-helper side. If nothing is done, an error is
 854                # thrown saying that HEAD is referring to unknown object 0000000000000000000
 855                # and the clone fails.
 856        }
 857}
 858
 859sub mw_import_ref_by_pages {
 860
 861        my $fetch_from = shift;
 862        my %pages_hash = get_mw_pages();
 863        my @pages = values(%pages_hash);
 864
 865        my ($n, @revisions) = fetch_mw_revisions(\@pages, $fetch_from);
 866
 867        @revisions = sort {$a->{revid} <=> $b->{revid}} @revisions;
 868        my @revision_ids = map $_->{revid}, @revisions;
 869
 870        return mw_import_revids($fetch_from, \@revision_ids, \%pages_hash);
 871}
 872
 873sub mw_import_ref_by_revs {
 874
 875        my $fetch_from = shift;
 876        my %pages_hash = get_mw_pages();
 877
 878        my $last_remote = get_last_global_remote_rev();
 879        my @revision_ids = $fetch_from..$last_remote;
 880        return mw_import_revids($fetch_from, \@revision_ids, \%pages_hash);
 881}
 882
 883# Import revisions given in second argument (array of integers).
 884# Only pages appearing in the third argument (hash indexed by page titles)
 885# will be imported.
 886sub mw_import_revids {
 887        my $fetch_from = shift;
 888        my $revision_ids = shift;
 889        my $pages = shift;
 890
 891        my $n = 0;
 892        my $n_actual = 0;
 893        my $last_timestamp = 0; # Placeholer in case $rev->timestamp is undefined
 894
 895        foreach my $pagerevid (@$revision_ids) {
 896                # Count page even if we skip it, since we display
 897                # $n/$total and $total includes skipped pages.
 898                $n++;
 899
 900                # fetch the content of the pages
 901                my $query = {
 902                        action => 'query',
 903                        prop => 'revisions',
 904                        rvprop => 'content|timestamp|comment|user|ids',
 905                        revids => $pagerevid,
 906                };
 907
 908                my $result = $mediawiki->api($query);
 909
 910                if (!$result) {
 911                        die "Failed to retrieve modified page for revision $pagerevid";
 912                }
 913
 914                if (defined($result->{query}->{badrevids}->{$pagerevid})) {
 915                        # The revision id does not exist on the remote wiki.
 916                        next;
 917                }
 918
 919                if (!defined($result->{query}->{pages})) {
 920                        die "Invalid revision $pagerevid.";
 921                }
 922
 923                my @result_pages = values(%{$result->{query}->{pages}});
 924                my $result_page = $result_pages[0];
 925                my $rev = $result_pages[0]->{revisions}->[0];
 926
 927                my $page_title = $result_page->{title};
 928
 929                if (!exists($pages->{$page_title})) {
 930                        print STDERR "$n/", scalar(@$revision_ids),
 931                                ": Skipping revision #$rev->{revid} of $page_title\n";
 932                        next;
 933                }
 934
 935                $n_actual++;
 936
 937                my %commit;
 938                $commit{author} = $rev->{user} || 'Anonymous';
 939                $commit{comment} = $rev->{comment} || EMPTY_MESSAGE;
 940                $commit{title} = mediawiki_smudge_filename($page_title);
 941                $commit{mw_revision} = $rev->{revid};
 942                $commit{content} = mediawiki_smudge($rev->{'*'});
 943
 944                if (!defined($rev->{timestamp})) {
 945                        $last_timestamp++;
 946                } else {
 947                        $last_timestamp = $rev->{timestamp};
 948                }
 949                $commit{date} = DateTime::Format::ISO8601->parse_datetime($last_timestamp);
 950
 951                # Differentiates classic pages and media files.
 952                my ($namespace, $filename) = $page_title =~ /^([^:]*):(.*)$/;
 953                my %mediafile;
 954                if ($namespace) {
 955                        my $id = get_mw_namespace_id($namespace);
 956                        if ($id && $id == get_mw_namespace_id("File")) {
 957                                %mediafile = get_mw_mediafile_for_page_revision($filename, $rev->{timestamp});
 958                        }
 959                }
 960                # If this is a revision of the media page for new version
 961                # of a file do one common commit for both file and media page.
 962                # Else do commit only for that page.
 963                print STDERR "$n/", scalar(@$revision_ids), ": Revision #$rev->{revid} of $commit{title}\n";
 964                import_file_revision(\%commit, ($fetch_from == 1), $n_actual, \%mediafile);
 965        }
 966
 967        return $n_actual;
 968}
 969
 970sub error_non_fast_forward {
 971        my $advice = run_git("config --bool advice.pushNonFastForward");
 972        chomp($advice);
 973        if ($advice ne "false") {
 974                # Native git-push would show this after the summary.
 975                # We can't ask it to display it cleanly, so print it
 976                # ourselves before.
 977                print STDERR "To prevent you from losing history, non-fast-forward updates were rejected\n";
 978                print STDERR "Merge the remote changes (e.g. 'git pull') before pushing again. See the\n";
 979                print STDERR "'Note about fast-forwards' section of 'git push --help' for details.\n";
 980        }
 981        print STDOUT "error $_[0] \"non-fast-forward\"\n";
 982        return 0;
 983}
 984
 985sub mw_upload_file {
 986        my $complete_file_name = shift;
 987        my $new_sha1 = shift;
 988        my $extension = shift;
 989        my $file_deleted = shift;
 990        my $summary = shift;
 991        my $newrevid;
 992        my $path = "File:" . $complete_file_name;
 993        my %hashFiles = get_allowed_file_extensions();
 994        if (!exists($hashFiles{$extension})) {
 995                print STDERR "$complete_file_name is not a permitted file on this wiki.\n";
 996                print STDERR "Check the configuration of file uploads in your mediawiki.\n";
 997                return $newrevid;
 998        }
 999        # Deleting and uploading a file requires a priviledged user
1000        if ($file_deleted) {
1001                mw_connect_maybe();
1002                my $query = {
1003                        action => 'delete',
1004                        title => $path,
1005                        reason => $summary
1006                };
1007                if (!$mediawiki->edit($query)) {
1008                        print STDERR "Failed to delete file on remote wiki\n";
1009                        print STDERR "Check your permissions on the remote site. Error code:\n";
1010                        print STDERR $mediawiki->{error}->{code} . ':' . $mediawiki->{error}->{details};
1011                        exit 1;
1012                }
1013        } else {
1014                # Don't let perl try to interpret file content as UTF-8 => use "raw"
1015                my $content = run_git("cat-file blob $new_sha1", "raw");
1016                if ($content ne "") {
1017                        mw_connect_maybe();
1018                        $mediawiki->{config}->{upload_url} =
1019                                "$url/index.php/Special:Upload";
1020                        $mediawiki->edit({
1021                                action => 'upload',
1022                                filename => $complete_file_name,
1023                                comment => $summary,
1024                                file => [undef,
1025                                         $complete_file_name,
1026                                         Content => $content],
1027                                ignorewarnings => 1,
1028                        }, {
1029                                skip_encoding => 1
1030                        } ) || die $mediawiki->{error}->{code} . ':'
1031                                 . $mediawiki->{error}->{details};
1032                        my $last_file_page = $mediawiki->get_page({title => $path});
1033                        $newrevid = $last_file_page->{revid};
1034                        print STDERR "Pushed file: $new_sha1 - $complete_file_name.\n";
1035                } else {
1036                        print STDERR "Empty file $complete_file_name not pushed.\n";
1037                }
1038        }
1039        return $newrevid;
1040}
1041
1042sub mw_push_file {
1043        my $diff_info = shift;
1044        # $diff_info contains a string in this format:
1045        # 100644 100644 <sha1_of_blob_before_commit> <sha1_of_blob_now> <status>
1046        my @diff_info_split = split(/[ \t]/, $diff_info);
1047
1048        # Filename, including .mw extension
1049        my $complete_file_name = shift;
1050        # Commit message
1051        my $summary = shift;
1052        # MediaWiki revision number. Keep the previous one by default,
1053        # in case there's no edit to perform.
1054        my $oldrevid = shift;
1055        my $newrevid;
1056
1057        if ($summary eq EMPTY_MESSAGE) {
1058                $summary = '';
1059        }
1060
1061        my $new_sha1 = $diff_info_split[3];
1062        my $old_sha1 = $diff_info_split[2];
1063        my $page_created = ($old_sha1 eq NULL_SHA1);
1064        my $page_deleted = ($new_sha1 eq NULL_SHA1);
1065        $complete_file_name = mediawiki_clean_filename($complete_file_name);
1066
1067        my ($title, $extension) = $complete_file_name =~ /^(.*)\.([^\.]*)$/;
1068        if (!defined($extension)) {
1069                $extension = "";
1070        }
1071        if ($extension eq "mw") {
1072                my $ns = get_mw_namespace_id_for_page($complete_file_name);
1073                if ($ns && $ns == get_mw_namespace_id("File") && (!$export_media)) {
1074                        print STDERR "Ignoring media file related page: $complete_file_name\n";
1075                        return ($oldrevid, "ok");
1076                }
1077                my $file_content;
1078                if ($page_deleted) {
1079                        # Deleting a page usually requires
1080                        # special privileges. A common
1081                        # convention is to replace the page
1082                        # with this content instead:
1083                        $file_content = DELETED_CONTENT;
1084                } else {
1085                        $file_content = run_git("cat-file blob $new_sha1");
1086                }
1087
1088                mw_connect_maybe();
1089
1090                my $result = $mediawiki->edit( {
1091                        action => 'edit',
1092                        summary => $summary,
1093                        title => $title,
1094                        basetimestamp => $basetimestamps{$oldrevid},
1095                        text => mediawiki_clean($file_content, $page_created),
1096                                  }, {
1097                                          skip_encoding => 1 # Helps with names with accentuated characters
1098                                  });
1099                if (!$result) {
1100                        if ($mediawiki->{error}->{code} == 3) {
1101                                # edit conflicts, considered as non-fast-forward
1102                                print STDERR 'Warning: Error ' .
1103                                    $mediawiki->{error}->{code} .
1104                                    ' from mediwiki: ' . $mediawiki->{error}->{details} .
1105                                    ".\n";
1106                                return ($oldrevid, "non-fast-forward");
1107                        } else {
1108                                # Other errors. Shouldn't happen => just die()
1109                                die 'Fatal: Error ' .
1110                                    $mediawiki->{error}->{code} .
1111                                    ' from mediwiki: ' . $mediawiki->{error}->{details};
1112                        }
1113                }
1114                $newrevid = $result->{edit}->{newrevid};
1115                print STDERR "Pushed file: $new_sha1 - $title\n";
1116        } elsif ($export_media) {
1117                $newrevid = mw_upload_file($complete_file_name, $new_sha1,
1118                                           $extension, $page_deleted,
1119                                           $summary);
1120        } else {
1121                print STDERR "Ignoring media file $title\n";
1122        }
1123        $newrevid = ($newrevid or $oldrevid);
1124        return ($newrevid, "ok");
1125}
1126
1127sub mw_push {
1128        # multiple push statements can follow each other
1129        my @refsspecs = (shift, get_more_refs("push"));
1130        my $pushed;
1131        for my $refspec (@refsspecs) {
1132                my ($force, $local, $remote) = $refspec =~ /^(\+)?([^:]*):([^:]*)$/
1133                    or die("Invalid refspec for push. Expected <src>:<dst> or +<src>:<dst>");
1134                if ($force) {
1135                        print STDERR "Warning: forced push not allowed on a MediaWiki.\n";
1136                }
1137                if ($local eq "") {
1138                        print STDERR "Cannot delete remote branch on a MediaWiki\n";
1139                        print STDOUT "error $remote cannot delete\n";
1140                        next;
1141                }
1142                if ($remote ne "refs/heads/master") {
1143                        print STDERR "Only push to the branch 'master' is supported on a MediaWiki\n";
1144                        print STDOUT "error $remote only master allowed\n";
1145                        next;
1146                }
1147                if (mw_push_revision($local, $remote)) {
1148                        $pushed = 1;
1149                }
1150        }
1151
1152        # Notify Git that the push is done
1153        print STDOUT "\n";
1154
1155        if ($pushed && $dumb_push) {
1156                print STDERR "Just pushed some revisions to MediaWiki.\n";
1157                print STDERR "The pushed revisions now have to be re-imported, and your current branch\n";
1158                print STDERR "needs to be updated with these re-imported commits. You can do this with\n";
1159                print STDERR "\n";
1160                print STDERR "  git pull --rebase\n";
1161                print STDERR "\n";
1162        }
1163}
1164
1165sub mw_push_revision {
1166        my $local = shift;
1167        my $remote = shift; # actually, this has to be "refs/heads/master" at this point.
1168        my $last_local_revid = get_last_local_revision();
1169        print STDERR ".\n"; # Finish sentence started by get_last_local_revision()
1170        my $last_remote_revid = get_last_remote_revision();
1171        my $mw_revision = $last_remote_revid;
1172
1173        # Get sha1 of commit pointed by local HEAD
1174        my $HEAD_sha1 = run_git("rev-parse $local 2>/dev/null"); chomp($HEAD_sha1);
1175        # Get sha1 of commit pointed by remotes/$remotename/master
1176        my $remoteorigin_sha1 = run_git("rev-parse refs/remotes/$remotename/master 2>/dev/null");
1177        chomp($remoteorigin_sha1);
1178
1179        if ($last_local_revid > 0 &&
1180            $last_local_revid < $last_remote_revid) {
1181                return error_non_fast_forward($remote);
1182        }
1183
1184        if ($HEAD_sha1 eq $remoteorigin_sha1) {
1185                # nothing to push
1186                return 0;
1187        }
1188
1189        # Get every commit in between HEAD and refs/remotes/origin/master,
1190        # including HEAD and refs/remotes/origin/master
1191        my @commit_pairs = ();
1192        if ($last_local_revid > 0) {
1193                my $parsed_sha1 = $remoteorigin_sha1;
1194                # Find a path from last MediaWiki commit to pushed commit
1195                print STDERR "Computing path from local to remote ...\n";
1196                my @local_ancestry = split(/\n/, run_git("rev-list --boundary --parents $local ^$parsed_sha1"));
1197                my %local_ancestry;
1198                foreach my $line (@local_ancestry) {
1199                        if (my ($child, $parents) = $line =~ m/^-?([a-f0-9]+) ([a-f0-9 ]+)/) {
1200                                foreach my $parent (split(' ', $parents)) {
1201                                        $local_ancestry{$parent} = $child;
1202                                }
1203                        } elsif (!$line =~ m/^([a-f0-9]+)/) {
1204                                die "Unexpected output from git rev-list: $line";
1205                        }
1206                }
1207                while ($parsed_sha1 ne $HEAD_sha1) {
1208                        my $child = $local_ancestry{$parsed_sha1};
1209                        if (!$child) {
1210                                printf STDERR "Cannot find a path in history from remote commit to last commit\n";
1211                                return error_non_fast_forward($remote);
1212                        }
1213                        push(@commit_pairs, [$parsed_sha1, $child]);
1214                        $parsed_sha1 = $child;
1215                }
1216        } else {
1217                # No remote mediawiki revision. Export the whole
1218                # history (linearized with --first-parent)
1219                print STDERR "Warning: no common ancestor, pushing complete history\n";
1220                my $history = run_git("rev-list --first-parent --children $local");
1221                my @history = split('\n', $history);
1222                @history = @history[1..$#history];
1223                foreach my $line (reverse @history) {
1224                        my @commit_info_split = split(/ |\n/, $line);
1225                        push(@commit_pairs, \@commit_info_split);
1226                }
1227        }
1228
1229        foreach my $commit_info_split (@commit_pairs) {
1230                my $sha1_child = @{$commit_info_split}[0];
1231                my $sha1_commit = @{$commit_info_split}[1];
1232                my $diff_infos = run_git("diff-tree -r --raw -z $sha1_child $sha1_commit");
1233                # TODO: we could detect rename, and encode them with a #redirect on the wiki.
1234                # TODO: for now, it's just a delete+add
1235                my @diff_info_list = split(/\0/, $diff_infos);
1236                # Keep the subject line of the commit message as mediawiki comment for the revision
1237                my $commit_msg = run_git("log --no-walk --format=\"%s\" $sha1_commit");
1238                chomp($commit_msg);
1239                # Push every blob
1240                while (@diff_info_list) {
1241                        my $status;
1242                        # git diff-tree -z gives an output like
1243                        # <metadata>\0<filename1>\0
1244                        # <metadata>\0<filename2>\0
1245                        # and we've split on \0.
1246                        my $info = shift(@diff_info_list);
1247                        my $file = shift(@diff_info_list);
1248                        ($mw_revision, $status) = mw_push_file($info, $file, $commit_msg, $mw_revision);
1249                        if ($status eq "non-fast-forward") {
1250                                # we may already have sent part of the
1251                                # commit to MediaWiki, but it's too
1252                                # late to cancel it. Stop the push in
1253                                # the middle, but still give an
1254                                # accurate error message.
1255                                return error_non_fast_forward($remote);
1256                        }
1257                        if ($status ne "ok") {
1258                                die("Unknown error from mw_push_file()");
1259                        }
1260                }
1261                unless ($dumb_push) {
1262                        run_git("notes --ref=$remotename/mediawiki add -f -m \"mediawiki_revision: $mw_revision\" $sha1_commit");
1263                        run_git("update-ref -m \"Git-MediaWiki push\" refs/mediawiki/$remotename/master $sha1_commit $sha1_child");
1264                }
1265        }
1266
1267        print STDOUT "ok $remote\n";
1268        return 1;
1269}
1270
1271sub get_allowed_file_extensions {
1272        mw_connect_maybe();
1273
1274        my $query = {
1275                action => 'query',
1276                meta => 'siteinfo',
1277                siprop => 'fileextensions'
1278                };
1279        my $result = $mediawiki->api($query);
1280        my @file_extensions= map $_->{ext},@{$result->{query}->{fileextensions}};
1281        my %hashFile = map {$_ => 1}@file_extensions;
1282
1283        return %hashFile;
1284}
1285
1286# In memory cache for MediaWiki namespace ids.
1287my %namespace_id;
1288
1289# Namespaces whose id is cached in the configuration file
1290# (to avoid duplicates)
1291my %cached_mw_namespace_id;
1292
1293# Return MediaWiki id for a canonical namespace name.
1294# Ex.: "File", "Project".
1295sub get_mw_namespace_id {
1296        mw_connect_maybe();
1297        my $name = shift;
1298
1299        if (!exists $namespace_id{$name}) {
1300                # Look at configuration file, if the record for that namespace is
1301                # already cached. Namespaces are stored in form:
1302                # "Name_of_namespace:Id_namespace", ex.: "File:6".
1303                my @temp = split(/[\n]/, run_git("config --get-all remote."
1304                                                . $remotename .".namespaceCache"));
1305                chomp(@temp);
1306                foreach my $ns (@temp) {
1307                        my ($n, $id) = split(/:/, $ns);
1308                        if ($id eq 'notANameSpace') {
1309                                $namespace_id{$n} = {is_namespace => 0};
1310                        } else {
1311                                $namespace_id{$n} = {is_namespace => 1, id => $id};
1312                        }
1313                        $cached_mw_namespace_id{$n} = 1;
1314                }
1315        }
1316
1317        if (!exists $namespace_id{$name}) {
1318                print STDERR "Namespace $name not found in cache, querying the wiki ...\n";
1319                # NS not found => get namespace id from MW and store it in
1320                # configuration file.
1321                my $query = {
1322                        action => 'query',
1323                        meta => 'siteinfo',
1324                        siprop => 'namespaces'
1325                };
1326                my $result = $mediawiki->api($query);
1327
1328                while (my ($id, $ns) = each(%{$result->{query}->{namespaces}})) {
1329                        if (defined($ns->{id}) && defined($ns->{canonical})) {
1330                                $namespace_id{$ns->{canonical}} = {is_namespace => 1, id => $ns->{id}};
1331                                if ($ns->{'*'}) {
1332                                        # alias (e.g. french Fichier: as alias for canonical File:)
1333                                        $namespace_id{$ns->{'*'}} = {is_namespace => 1, id => $ns->{id}};
1334                                }
1335                        }
1336                }
1337        }
1338
1339        my $ns = $namespace_id{$name};
1340        my $id;
1341
1342        unless (defined $ns) {
1343                print STDERR "No such namespace $name on MediaWiki.\n";
1344                $ns = {is_namespace => 0};
1345                $namespace_id{$name} = $ns;
1346        }
1347
1348        if ($ns->{is_namespace}) {
1349                $id = $ns->{id};
1350        }
1351
1352        # Store "notANameSpace" as special value for inexisting namespaces
1353        my $store_id = ($id || 'notANameSpace');
1354
1355        # Store explicitely requested namespaces on disk
1356        if (!exists $cached_mw_namespace_id{$name}) {
1357                run_git("config --add remote.". $remotename
1358                        .".namespaceCache \"". $name .":". $store_id ."\"");
1359                $cached_mw_namespace_id{$name} = 1;
1360        }
1361        return $id;
1362}
1363
1364sub get_mw_namespace_id_for_page {
1365        if (my ($namespace) = $_[0] =~ /^([^:]*):/) {
1366                return get_mw_namespace_id($namespace);
1367        } else {
1368                return;
1369        }
1370}