Bug 33690: Convert to x-koha-override

This patch converts the existing work to use x-koha-override instead of
introducing an entirely new header and we default to the system
preference value if the override isn't passed.

I believe this is more consistent with our approach in other areas of
koha to date.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>

Koha/REST/V1/Patrons.pm

@@ -116,7 +116,10 @@ sub add {
 
                 my $patron = Koha::Patron->new_from_api($body)->store;
 
-                if ( $c->req->headers->header('x-koha-welcome') ) {
+                my $overrides = $c->stash('koha.overrides');
+                if ( $overrides->{welcome_yes}
+                    || ( C4::Context->preference("AutoEmailNewUser") && !$overrides->{welcome_no} ) )
+                {
 
                     # if we manage to find a valid email address, send notice
                     if ( $patron->notice_email_address ) {

api/v1/swagger/paths/patrons.yaml

@@ -405,11 +405,17 @@
         required: true
         schema:
           $ref: "../swagger.yaml#/definitions/patron"
-      - name: x-koha-welcome
+      - name: x-koha-override
         in: header
         required: false
-        description: If set to 'email' triggers the sending of a welcome email
-        type: string
+        description: Overrides list sent as a request header
+        type: array
+        items:
+          type: string
+          enum:
+            - welcome_yes
+            - welcome_no
+        collectionFormat: csv
     consumes:
       - application/json
     produces:

t/db_dependent/api/v1/patrons.t

@@ -408,8 +408,10 @@ subtest 'add() tests' => sub {
         # Set a date-time field
         $newpatron->{last_seen} = output_pref({ dt => dt_from_string->add( days => -1 ), dateformat => 'rfc3339' });
 
+        t::lib::Mocks::mock_preference( 'AutoEmailNewUser', 0 );
         $letter_enqueued = 0;
-        $t->post_ok("//$userid:$password@/api/v1/patrons" => { 'x-koha-welcome' => 'email' } => json => $newpatron)
+        $t->post_ok(
+            "//$userid:$password@/api/v1/patrons" => { 'x-koha-override' => 'welcome_yes' } => json => $newpatron )
           ->status_is(201, 'Patron created successfully')
           ->header_like(
             Location => qr|^\/api\/v1\/patrons/\d*|,