Added controller method for improving/simplifying param reading

With a growing use of the same pattern of reading parameters
from either the URL or the body, this method allows reuse and
simplification of the route handlers code.

Author: mickeyn

lib/MetaCPAN/Server.pm

@@ -9,6 +9,7 @@ use CatalystX::RoleApplicator;
 use File::Temp qw( tempdir );
 use Plack::Middleware::ReverseProxy;
 use Plack::Middleware::ServerStatus::Lite;
+use Ref::Util qw( is_arrayref );
 
 extends 'Catalyst';
 
@@ -124,6 +125,27 @@ sub to_app {
     return $app;
 }
 
+# a controller method to read a given parameter key which will be read
+# from either the URL (query parameter) or from the (JSON) deserialized
+# request body (not both, 'body' parameters take precedence).
+# the returned output is an arrayref containing the parameter values.
+sub read_param {
+    my ( $c, $key ) = @_;
+
+    my $body_data = $c->req->body_data;
+    my $params
+        = $body_data
+        ? $body_data->{$key}
+        : [ $c->req->param($key) ];
+
+    $params = [$params] unless is_arrayref($params);
+
+    $c->detach( '/bad_request', ["Missing param: $key"] )
+        unless $params and @{$params};
+
+    return $params;
+}
+
 1;
 
 __END__

lib/MetaCPAN/Server/Controller/Author.pm

@@ -76,14 +76,7 @@ sub qsearch : Path('search') : Args(0) {
 # /author/by_ids?id=PAUSE_ID1&id=PAUSE_ID2...
 sub by_ids : Path('by_ids') : Args(0) {
     my ( $self, $c ) = @_;
-    my $body_data = $c->req->body_data;
-    my $ids
-        = $body_data
-        ? $body_data->{id}
-        : [ $c->req->param('id') ];
-    $c->detach( '/bad_request', ['No ids requested'] )
-        unless $ids and @{$ids};
-    my $data = $self->model($c)->raw->by_ids($ids);
+    my $data = $self->model($c)->raw->by_ids( $c->read_param('id') );
 
     $data
         ? $c->stash($data)
@@ -105,16 +98,7 @@ sub by_user : Path('by_user') : Args(1) {
 # /author/by_user?user=USER_ID1&user=USER_ID2...
 sub by_users : Path('by_user') : Args(0) {
     my ( $self, $c ) = @_;
-
-    my $body_data = $c->req->body_data;
-    my $users
-        = $body_data
-        ? $body_data->{user}
-        : [ $c->req->param('user') ];
-    $c->detach( '/bad_request', ['No users requested'] )
-        unless $users and @{$users};
-
-    my $data = $self->model($c)->raw->by_user($users);
+    my $data = $self->model($c)->raw->by_user( $c->read_param('user') );
 
     $data
         ? $c->stash($data)

lib/MetaCPAN/Server/Controller/Favorite.pm

@@ -73,21 +73,9 @@ sub leaderboard : Path('leaderboard') : Args(0) {
 
 sub agg_by_distributions : Path('agg_by_distributions') : Args(0) {
     my ( $self, $c ) = @_;
-    my $body_data = $c->req->body_data;
-
-    my $distributions
-        = $body_data
-        ? $body_data->{distribution}
-        : [ $c->req->param('distribution') ];
-    $c->detach( '/bad_request', ['No distributions requested'] )
-        unless $distributions and @{$distributions};
-
-    my $user
-        = $body_data
-        ? $body_data->{user}
-        : $c->req->param('user');
-
-    my $data = $self->model($c)
+    my $distributions = $c->read_param('distribution');
+    my $user          = $c->read_param('user');
+    my $data          = $self->model($c)
         ->raw->agg_by_distributions( $distributions, $user );
 
     $data

lib/MetaCPAN/Server/Controller/Permission.pm

@@ -29,14 +29,7 @@ sub by_module : Path('by_module') : Args(1) {
 
 sub by_modules : Path('by_module') : Args(0) {
     my ( $self, $c ) = @_;
-    my $modules
-        = $c->req->body_data
-        ? $c->req->body_data->{module}
-        : [ $c->req->param('module') ];
-    $c->detach( '/bad_request', ['No modules requested'] )
-        unless $modules and @{$modules};
-
-    my $data = $self->model($c)->raw->by_modules($modules);
+    my $data = $self->model($c)->raw->by_modules( $c->read_param('module') );
 
     $data
         ? $c->stash($data)

lib/MetaCPAN/Server/Controller/Rating.pm

@@ -11,14 +11,8 @@ with 'MetaCPAN::Server::Role::JSONP';
 
 sub by_distributions : Path('by_distributions') : Args(0) {
     my ( $self, $c ) = @_;
-    my $distributions
-        = $c->req->body_data
-        ? $c->req->body_data->{distribution}
-        : [ $c->req->param('distribution') ];
-    $c->detach( '/bad_request', ['No distributions requested'] )
-        unless $distributions and @{$distributions};
-
-    my $data = $self->model($c)->raw->by_distributions($distributions);
+    my $data = $self->model($c)
+        ->raw->by_distributions( $c->read_param('distribution') );
 
     $data
         ? $c->stash($data)