From 941f3fd80a4e9c96821a5e50f05bb04cf356304c Mon Sep 17 00:00:00 2001
From: Damyan Ivanov <dmn@debian.org>
Date: Tue, 15 Feb 2022 21:12:29 +0000
Subject: [PATCH] return exception responses as JSON

---
 lib/App/LazyShoppingList/API.pm    | 11 ++++++++---
 lib/App/LazyShoppingList/API/v1.pm | 28 +++++++---------------------
 2 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/lib/App/LazyShoppingList/API.pm b/lib/App/LazyShoppingList/API.pm
index c828974..84e7fad 100644
--- a/lib/App/LazyShoppingList/API.pm
+++ b/lib/App/LazyShoppingList/API.pm
@@ -9,7 +9,7 @@ use Exporter qw(import);
 our $VERSION = '0.1';
 
 our @EXPORT = qw( &get_database &get_lists_version &increment_lists_version
-    &invalid_input );
+    &invalid_input exception );
 
 use Dancer2::Plugin::DBIC;
 
@@ -66,8 +66,13 @@ sub increment_lists_version($dbh) {
 }
 
 sub invalid_input($details = undef) {
-    status 400;
-    return "Invalid input" . ( defined($details) ? " ($details)" : '' );
+    return exception 400,
+        "Invalid input" . ( defined($details) ? " ($details)" : '' );
+}
+
+sub exception($http_code, $text) {
+    status $http_code;
+    return { exception => $text };
 }
 
 
diff --git a/lib/App/LazyShoppingList/API/v1.pm b/lib/App/LazyShoppingList/API/v1.pm
index 8a30acb..f94db2e 100644
--- a/lib/App/LazyShoppingList/API/v1.pm
+++ b/lib/App/LazyShoppingList/API/v1.pm
@@ -13,9 +13,7 @@ use JSON();
 use experimental 'signatures';
 
 set charset      => 'UTF-8';
-set serializer   => 'JSON';
-set content_type => 'application/json';
-
+set serializer => 'JSON';
 
 # get the URI for the list of shopping lists
 get '/' => sub {
@@ -48,9 +46,7 @@ post '/list' => sub {
 
     my $name = $req->{name};
     unless ($name) {
-        status 400;
-        content_type 'text/plain';
-        return "Missing list name";
+        return exception 400, "Missing list name";
     }
 
     my $dbh = get_database;
@@ -87,9 +83,7 @@ get '/list/:list_id' => sub {
 
     unless ($list) {
         $dbh->txn_commit;
-        status 404;
-        content_type 'text/plain';
-        return "No list with that ID found";
+        return exception 404, "No list with that ID found";
     }
 
     $r{version} = $list->version;
@@ -133,9 +127,7 @@ post '/list/:id' => sub {
 
     unless ($list) {
         $dbh->txn_commit;
-        status 404;
-        content_type 'text/plain';
-        return "No such list";
+        exception 404, "No such list";
     }
 
     my $item = $dbh->resultset('ShoppingListItem')->create(
@@ -186,17 +178,13 @@ put '/list/:list_id/:item_id' => sub {
     my $list = $dbh->resultset('ShoppingList')->find($list_id);
     unless ($list) {
         $dbh->txn_commit;
-        status 404;
-        content_type 'text/plain';
-        return "No such list";
+        return exception 404, "No such list";
     }
 
     my $item = $dbh->resultset('ShoppingListItem')->find({shopping_list => $list->id, id => $item_id});
     unless ($item) {
         $dbh->txn_commit;
-        status 404;
-        content_type 'text/plain';
-        return "No such item";
+        return exception 404, "No such item";
     }
 
     # in case no real changes are needed will return the current state
@@ -205,9 +193,7 @@ put '/list/:list_id/:item_id' => sub {
     {
         unless ($version == $item->version) {
             $dbh->txn_commit;
-            status 409;
-            content_type 'text/plain';
-            return
+            return exception 409, exception =>
                 sprintf( 'Outdated version (current is %d)', $item->version );
         }
 
-- 
2.39.5