API: Fix incorrect parameter handling

Array or hash parameters require '[]' suffix when passed to API. This
commit fixes problems when the suffix was not added for other than GET
requests (notably POST and PUT).

GitLab/API.pm

@@ -202,10 +202,22 @@ sub create_uri {
 
     # add query parameters
     foreach my $param (@{$tmpl->{query} // []}) {
+        my $type = '';
+        if ($param =~ s/\[\]$//) {
+            $type = 'ARRAY';
+        } elsif ($param =~ s/\{\}//) {
+            $type = 'HASH';
+        }
+
         if (exists $args->{$param}) {
+            if (ref $args->{$param} ne $type) {
+                croak "Argument '$param' is expected to be of type '$type',
+                        but '" . ref($args->{$param}) . "' is provided";
+            }
+
             if (ref $args->{$param} eq "ARRAY") {
                 foreach my $val (@{ $args->{$param} }) {
-                    $uri->query_param_append($param, $val);
+                    $uri->query_param_append("$param\[\]", $val);
                 }
             } elsif (ref $args->{$param} eq "HASH") {
                 while (my ($key, $val) = each %{$args->{$param}}) {
@@ -214,6 +226,7 @@ sub create_uri {
             } else {
                 $uri->query_param_append($param => $args->{$param});
             }
+
             delete $args->{$param};
         }
     }
@@ -221,6 +234,47 @@ sub create_uri {
     return $uri;
 }
 
+sub _param_exists {
+    my ($self, $tmpl, $param) = @_;
+
+    return grep { $_ eq $param }
+        @{ $tmpl->{optional} // [] },
+        @{ $tmpl->{required} // [] };
+}
+
+sub process_post_args {
+    my ($self, $tmpl, $args) = @_;
+
+    my @result;
+    foreach my $param (keys %$args) {
+        if (ref $args->{$param} eq 'ARRAY') {
+            if (!$self->_param_exists($tmpl, $param . '[]')) {
+                croak "$param: Is an array but $param\[\] is not allowed for this request";
+            }
+
+            foreach my $value (@{ $args->{$param} }) {
+                push @result, "$param\[\]", $value;
+            }
+        } elsif (ref $args->{$param} eq 'HASH') {
+            if (!$self->_param_exists($tmpl, $param . '{}')) {
+                croak "$param: Is a hash but $param\{\} is not allowed for this request";
+            }
+
+            foreach my $key (sort keys %{ $args->{$param} }) {
+                push @result, "$param\[$key\]", $args->{$param}->{$key};
+            }
+        } else {
+            if (!$self->_param_exists($tmpl, $param)) {
+                croak "$param: Is a scalar but $param is not allowed for this request";
+            }
+
+            push @result, $param, $args->{$param};
+        }
+    }
+
+    return @result;
+}
+
 sub clean_data {
     my ($self, $response) = @_;
 
@@ -277,13 +331,17 @@ sub exec_request {
     croak "Missing arguments [" . join(", ", @missing) . "] for '$tmpl->{name}'" if scalar @missing;
 
     # validate optional arguments
-    my %allargs = map { $_ => 1 } (@{$tmpl->{required}}, @{$tmpl->{optional}});
-    my @extra   = grep { !defined $allargs{$_} } keys %$args;
+    my %allargs = map { ($_ =~ s/(\[\]|\{\})$//gr) => 1 }
+            (@{$tmpl->{required}}, @{$tmpl->{optional}});
+
+    my @extra   = grep { !defined $allargs{$_} }
+            keys %$args;
+
     carp "Extra arguments [" . join(", ", @extra) . "] for '$tmpl->{name}'" if scalar @extra;
 
-    my @postdata    = %$args;
+    my @postdata = $self->process_post_args($tmpl, $args);
+    my $data = [];
     my $response;
-    my $data        = [];
 
     croak "Cannot request -iterator if -page is specified as well"
         if $rtargs->{-iterator} && defined $rtargs->{-page};