summaryrefslogtreecommitdiffstats
path: root/Bugzilla/WebService/Util.pm
blob: 51e45cc146955b4350a2c2bb28da4c6394666829 (plain)
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
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This Source Code Form is "Incompatible With Secondary Licenses", as
# defined by the Mozilla Public License, v. 2.0.

package Bugzilla::WebService::Util;
use strict;
use base qw(Exporter);

# We have to "require", not "use" this, because otherwise it tries to
# use features of Test::More during import().
require Test::Taint;

our @EXPORT_OK = qw(
    filter
    filter_wants
    taint_data
    validate
    translate
    params_to_objects
);

sub filter ($$) {
    my ($params, $hash) = @_;
    my %newhash = %$hash;

    foreach my $key (keys %$hash) {
        delete $newhash{$key} if !filter_wants($params, $key);
    }

    return \%newhash;
}

sub filter_wants ($$) {
    my ($params, $field) = @_;
    my %include = map { $_ => 1 } @{ $params->{'include_fields'} || [] };
    my %exclude = map { $_ => 1 } @{ $params->{'exclude_fields'} || [] };

    if (defined $params->{include_fields}) {
        return 0 if !$include{$field};
    }
    if (defined $params->{exclude_fields}) {
        return 0 if $exclude{$field};
    }

    return 1;
}

sub taint_data {
    my @params = @_;
    return if !@params;
    # Though this is a private function, it hasn't changed since 2004 and
    # should be safe to use, and prevents us from having to write it ourselves
    # or require another module to do it.
    Test::Taint::_deeply_traverse(\&_delete_bad_keys, \@params);
    Test::Taint::taint_deeply(\@params);
}

sub _delete_bad_keys {
    foreach my $item (@_) {
        next if ref $item ne 'HASH';
        foreach my $key (keys %$item) {
            # Making something a hash key always untaints it, in Perl.
            # However, we need to validate our argument names in some way.
            # We know that all hash keys passed in to the WebService will 
            # match \w+, so we delete any key that doesn't match that.
            if ($key !~ /^\w+$/) {
                delete $item->{$key};
            }
        }
    }
    return @_;
}

sub validate  {
    my ($self, $params, @keys) = @_;

    # If $params is defined but not a reference, then we weren't
    # sent any parameters at all, and we're getting @keys where
    # $params should be.
    return ($self, undef) if (defined $params and !ref $params);
    
    # If @keys is not empty then we convert any named 
    # parameters that have scalar values to arrayrefs
    # that match.
    foreach my $key (@keys) {
        if (exists $params->{$key}) {
            $params->{$key} = ref $params->{$key} 
                              ? $params->{$key} 
                              : [ $params->{$key} ];
        }
    }

    return ($self, $params);
}

sub translate {
    my ($params, $mapped) = @_;
    my %changes;
    while (my ($key,$value) = each (%$params)) {
        my $new_field = $mapped->{$key} || $key;
        $changes{$new_field} = $value;
    }
    return \%changes;
}

sub params_to_objects {
    my ($params, $class) = @_;

    my @objects = map { $class->check($_) } 
        @{ $params->{names} } if $params->{names};

    my @objects_by_ids = map { $class->check({ id => $_ }) } 
        @{ $params->{ids} } if $params->{ids};

    push(@objects, @objects_by_ids);
    my %seen;
    @objects = grep { !$seen{$_->id}++ } @objects;
    return \@objects;
}

__END__

=head1 NAME

Bugzilla::WebService::Util - Utility functions used inside of the WebService
code. These are B<not> functions that can be called via the WebService.

=head1 DESCRIPTION

This is somewhat like L<Bugzilla::Util>, but these functions are only used
internally in the WebService code.

=head1 SYNOPSIS

 filter({ include_fields => ['id', 'name'], 
          exclude_fields => ['name'] }, $hash);
 my $wants = filter_wants $params, 'field_name';
 validate(@_, 'ids');

=head1 METHODS

=head2 filter

This helps implement the C<include_fields> and C<exclude_fields> arguments
of WebService methods. Given a hash (the second argument to this subroutine),
this will remove any keys that are I<not> in C<include_fields> and then remove
any keys that I<are> in C<exclude_fields>.

=head2 filter_wants

Returns C<1> if a filter would preserve the specified field when passing
a hash to L</filter>, C<0> otherwise.

=head2 validate

This helps in the validation of parameters passed into the WebSerice
methods. Currently it converts listed parameters into an array reference
if the client only passed a single scalar value. It modifies the parameters
hash in place so other parameters should be unaltered.

=head2 translate

WebService methods frequently take parameters with different names than
the ones that we use internally in Bugzilla. This function takes a hashref
that has field names for keys and returns a hashref with those keys renamed
according to the mapping passed in with the second parameter (which is also
a hashref).

=head2 params_to_objects

Creates objects of the type passed in as the second parameter, using the
parameters passed to a WebService method (the first parameter to this function).
Helps make life simpler for WebService methods that internally create objects
via both "ids" and "names" fields. Also de-duplicates objects that were loaded
by both "ids" and "names". Returns an arrayref of objects.